> My question is there any way to test the antenna for
> possible issues? For example, if I put an ohm meter
> on the antenna connections, should I get 300 ohms?

The 300 Ohms is the AC impedance at RF frequencies.
A DC Ohm meter might read 0 Ohms (UHF loop) or
infinity (rabbit ears). In addition, the impedance
will almost certainly vary significantly with
frequency, there might only be 1 or 2 frequencies that
are actually 300 Ohms.

You can do a visual inspection. Make sure everything is
assembled correctly, no missing or extra pieces, nothing
bent or otherwise damaged.

Make sure you have the antenna pointed in the correct direction.
It might be that the front and back of the antenna are reversed
from what you think. (Yes, people have done this.)

If you can't see the towers and are aiming with a compass,
make sure the directions you are using are for magnetic north
rather than true north.

After installing the antenna on my roof and aligning it, I wasn't getting anything at all from NYC, so I shifted to my WTNH fallback, and I'm only getting a signal in the mid 30's on my DirecTV HR-20 receiver. The station is supposed to be about 30 miles away. I know I'm in a valley, but I really expected to be able to get at least this channel.

You may want to run a TVFool.com plot for your location. A general ZIP code (06776) plot of the area shows WTNH as your best bet, but at -86dBm. However, it sounds like you may be in a tougher spot than the general ZIP plot is showing.

Are you using a pre-amp?

Are you using a pre-amp?

No. I didn't really think I would need any amps for 30 miles with an antenna rated at 100+ miles for VHF.

And I know it is not uncommon to have the antenna backwards, but it is correct. I even doubted myself when I wasn't getting a signal & spun it around to double check.

Please post a TVFool file for your exact address. Falcon_77 is right that TVFool can be very location-specific, especially if you use lat/long. (And include before/after transition). If nothing else, it'll give folks here some idea what's available to your antenna. Your zip code looks atrocious, but if you were on the right hill, that all could change. Distance isn't as important as what's in the way.

The pre-amp may not be needed for signal level, but rather signal-to-noise ratio, to enable a signal lock.

The other thing to note is how does analog channel 8 look. Is there any snow or ghosts? Aiming a long antenna is best done with the picture watched as the antenna is turned and peaking for best signal. The best picture on channel 8 will produce the best chance of getting WTNH DT.
John

Here are the before & after images from tvfool.

The other thing to note is how does analog channel 8 look. Is there any snow or ghosts? Aiming a long antenna is best done with the picture watched as the antenna is turned and peaking for best signal. The best picture on channel 8 will produce the best chance of getting WTNH DT.
John

Believe it or not, I actually don't have anything with an analog tuner in that room. I'm going to hook up a VCR temporarily to see the analog quality. I'll post the results tomorrow night.

No. I didn't really think I would need any amps for 30 miles with an antenna rated at 100+ miles for VHF.

Distance measurements are a "rough" indicator or relative gain, but aren't very useful in the real world, especially in situations like yours.

After reviewing the TV Fool plot, I would still suggest trying a pre-amp, like a CM7777. However, -84dBm shouldn't be hard to receive w/o one, so perhaps something else is amiss. How high above the roof is the antenna? I'm assuming it is a wooded area as well?

A look at analog WTNH 8, as suggested by John, would be a good idea. I would be curious to know what else can be seen on analog.

Tmullen,
You are in a fringe to deep fringe area, regardless of your distance from transmitters. I'm in a valley, and need an attic antenna at 7 miles. You're several valleys worse off than me!

You've got the right idea in the 6971; a big VHF/UHF antenna, but it still needs help to deliver the most usable signal. I'd put a low noise pre-amp close to the antenna, so you can see what this baby can really do. I assume you've got good coax to your tuner with professional terminations outside; waterproof the pre-amp connections as best you can.

It'll also be important to aim accurately; do you have a rotor on it? I doubt you can get both Hartford and New Haven directions at once, and you may need to fine tune within those directions.

The last thing would be to upgrade the UHF section. The 6971 has the UHF gain profile of a 4-bay bow-tie, very good but you could upgrade to an 8-bay or high-end Yagi. It comes down to how badly you want to watch PBS ...

Frank

I'm looking into getting an OTA antenna. (a small indoor one that I can move if I need to)

My first question is: can I have the antenna hooked up as well as a coax cable connection at the same time? I have no other way of connecting my cable TV (I live in a dorm, so there's no cable box like with a company like Comcast/Time Warner/etc.) and I want to get better digital/HD reception on the OTA channels, but I don't want to sacrifice the channels I get over the coax connection. Is there any solution to this problem? I've never bought/seen an OTA so I didn't know how they connect, or if they can be connected at the same time.

Thanks for all your help, in advance.

TuxBobble,
Some quick questions. I'll assume you're set up llike my daughter's dorm, with a coax cable signal feed that screws onto the back of the set.
- does the TV have a tuner (vs "HD Ready" sets)?
- if so, does it tune NTSC, ATSC, QAM or a combination?
- does the TV have separate "antenna" and "cable" screw connections?

As long as you have a tuner, you can use an antenna. If there are separate ANT and CBL connections, both will hook to the TV and it'll switch inputs. If there's only one input on your TV, an external RF switch ($5-10) can allow you to select between cable and OTA.

The type of tuner determines what signals you can see. NTSC is classic analog TV that's going away Feb. 2009 (TVs are still usable through use of a converter box). ATSC is its digital replacement available now but with some channel changes 2/09. QAM is a digital cable TV tuner, for tuning digital cable without a STB.

Finally, go to TVFool.com and find out what channel signal strengths look like where you live. Posting that, now and post-transition, will be very helpful as well.

That's the basics, what have you got?
Frank

- does the TV have a tuner (vs "HD Ready" sets)?


To clarify this point, look for an integrated ATSC/QAM tuner. All new TV's sold since March of last year have at least ATSC (and most QAM), but the easiest way to find out on yours is to look at your remote. Does it have a "." or a "-" next to the number input area?

"HD Ready" means that a TV can accept HD sources through component, etc., but those do not have a tuner.

To clarify this point, look for an integrated ATSC/QAM tuner. All new TV's sold since March of last year have at least ATSC (and most QAM), but the easiest way to find out on yours is to look at your remote. Does it have a "." or a "-" next to the number input area?


Could you be a little more explicit about what "." means, and what "-" means?

Could you be a little more explicit about what "." means, and what "-" means?"." means "dot", and "-" means "dash".:D

As in subchannels 3.1, 3.2, or 3-1, 3-2. A digital tuner remote will have these channel options, in place of plain old analog 3. It's one sign of an ATSC tuner.

As in subchannels 3.1, 3.2, or 3-1, 3-2. A digital tuner remote will have these channel options, in place of plain old analog 3. It's one sign of an ATSC tuner.

See the attached picture for an example. This is for my small Westinghouse TV with an integrated tuner. Some use a "." and some a "-" but it does the same thing.

This TV allows me to just enter "2" w/o a dot, to get 2.1 when I'm in digital mode. However, my other TV plays dumb. If I don't enter a 2.1 on my Sony it will pull up a screen that says "no signal." It also has a separate digital mode vs. analog mode (unlike the Samsungs I've seen), so this behavior is puzzling.

My TV does have a "." on the remote. But before I got to that explanation I looked on the box and found out that it has a built in ATSC/QAM/NTSC tuner. Easier since the box is right next to me. (I held onto it for transporting the TV places--it's a 26" and therefore is mobile enough to bring with me between my dorm and my house. There is no antenna hookup, only a cable coax. So I assume I'd need some sort of switch, as fbov said, to add an antenna onto it?

I looked at TVFool.com and it was somewhat helpful in identifying signal strengths and what's available in the area, both at home and in my dorm room. Thanks for that information. I guess it really comes down to whether I want the inconvenience of the switcher or not, haha...

I've had a weird degradation in reception affecting only one channel that started a little over a month ago. Zip is 49417 and I'm 25-40 miles from my local towers and have had good luck pulling all stations in with an attic mounted antenna. I have available to me both a RS VU-75 VHF/UHF antenna as well as Winegard YA1713 VHF + CM 4221 UHF setup. I use a CM 7777 preamp and a 100' run of RG6.

One of the stations - WOOD-DT 8.1 broadcasting on VHF 7 - dropped in signal strength about a month ago. It used to be solid with very few droputs. Then a month ago dropped to ok but more frequent dropouts. In the last few days it has gotten really bad and is unwatchable. At each of those three phases of reception quality, the signal strength readings on both my Series 3 Tivo and Samsung DTB-H260F tuners has dropped accordingly. On the Tivo, signal strength used to be in the low 80's. Then a month ago dropped to the mid 60's, and now it's at 50 or worse.

I did the following to try to isolate the problem:

1) Ran 25' coax directly from antenna to tuner
2) Swapped antennas
3) Swapped tuner hardware

None of these actions made a difference. The strange thing is that all other locals are unchanged and come in at the same strength they always have. Only WOOD-DT on VHF 7 has deteriorated.

I contacted the station engineer and he told me nothing has changed on the broadcast side. I keep up with the AVS Grand Rapids HDTV thread and asked whether anybody has had trouble with WOOD-DT. No one has.

What could cause VHF 7 to go south while all other channels are unchanged? Could it be the preamp (the only thing I haven't swapped out so far)? Or perhaps some RF interference in the neighborhood or my house that affects VHF 7?

Any thoughts or advice would be greatly appreciated. Thanks!

What could cause VHF 7 to go south while all other channels are unchanged? Could it be the preamp (the only thing I haven't swapped out so far)? Or perhaps some RF interference in the neighborhood or my house that affects VHF 7?


It sounds like something in your area may be putting out noise on VHF 7. Have you noticed any difference in the signal on analog 8?

I know that bad power lines can significantly affect Low-VHF reception, but I'm not sure on upper VHF. Maybe it's time for the power company to check your local lines to see if any insulators have cracked, etc.

Did you get a new computer? I have seen those cause problems to my analog upper VHF signals.

I've noodled this for a bit, and the one thing that explains it is if the VHF section of the pre-amp is dying. Easy to test - cut the power and see if the signal drops. No change in signal is a clear indicator.

If the pre-amp's working, you're back to Falcon_77's ideas, or big new construction between you and the transmitter.

good luck, Frank

You can't just "cut power" to a Preamp....it becomes a very effective
attenuator (kills the signal). You have to physically bypass or remove it....

If you take down the antenna, while you're at it, try hunting around
(incl. up/down) looking for CH7:
http://www.hdtvprimer.com/ANTENNAS/siting.html

Judging by the length of this thread, I may be beating a dead horse, but so much reading only confuses me more, rather than less. But this thread also appears to be a place to find people that know enough to make my quest a bit easier.

I just got and installed a FusionHDTV7 Gold RT tuner yesterday, but I have not yet bought a new antenna. I have a pair of Radio Shack rabbit ears that I used for testing. When the software scanned the channels, it only found analog channels, and then only 4 out of 15 stations available, and only 2 that displayed...no HDTV channels.

From comments that I have read, people in Australia have no problems receiving digital channels on any antennas, but then they use DVB T tuners instead of ATSC,

Without rambling too much, it boils down to choosing a new antenna. I live in a complex that prohibits attaching any antennas to the building, so I'm limited to something that I can mount on the patio (probably using a mast running through the umbrella hole on the patio table. This limits height considerably to 6-8 feet. I would prefer a multi-directional antenna to eliminate or reduce having to manually adjust to channels, but all of the digital stations are spread on the compass rose between Southeast and Southwest, except one that is Northeast. If I include the analog stations, then they would cover the entire compass rose.The distance of most of the stations vary between 5-25 miles, except one that is 73 miles. Other factors (terrain, obstructions, etc.) aren't too bad. I only want to spend between $50 to $100, but I'm wondering if this amount would be a waste and I should spend more?

All inputs appreciated.

You can't just "cut power" to a Preamp....it becomes a very effective
attenuator (kills the signal). You have to physically bypass or remove it....
...

Agreed, but that's the power of the test when one suspects a malfunctioning pre-amp. If the pre-amp is working, he sees a big difference. If it's malfunctioning, it's already an effective attentuator and he sees no difference. And his feet stay on the ground.

You are correct that cutting power does not test effectiveness of a functioning pre-amp - you have to bypass the functioning pre-amp to see if it's doing what you want.

But ghken has a fairly high-end set-up, and may well have had it installed for some time. If his pre-amp has been progressively biting the big one, it explains his observations, and it's easy to test. Make sense?

Frank

seekermeister,
you mention Australia and DTB-T - where are you?

If in the US (only, I beleieve) you can ask for a station location and signal analysis at TVFool.com. Put in your exact street address, or better, the long/lat of your proposed antenna location. Post it here and we'll be able to give you some concrete recommendations. 25 miles line-of-sight (LOS) may still be rabbit ear territory, or a low spot at 7 miles with a few hills in the way may require a long-distance antenna.

Balconies will alway do well in the direction they face, and poorly in the opposite due to the building, but as areas of exclusive use, you have a Federal right to an antenna. And there are some good, inexpensive antennas. The actual recommendation will depend on channels, directions and signal strengths, and will likely fit your budget.

Have fun, Frank

I don't think there are any Radio Shacks in Australia. I'm guessing that he was reading Fusion reviews, many of which were done in Australia. As for no problems on any antennas there, it is probably for a single review. Reading the Australian board (http://www.dtvforum.info/) will show plenty of problems with reception there as well.

seekermeister, if you can provide your ZIP code, we can run a general area plot from TVFool.com to check your prospects for reception.

Sorry for this last post, but I was just wondering if anyone had any positive experience with specific small, indoor, HD antennas (directional or omni, doesn't matter) that they could share. I'll be in the Philadelphia area, or in the NYC area, depending on if I'm home or at school, if that helps...

Agreed, but that's the power of the test when one suspects a malfunctioning pre-amp. If the pre-amp is working, he sees a big difference. If it's malfunctioning, it's already an effective attentuator and he sees no difference. And his feet stay on the ground.

You are correct that cutting power does not test effectiveness of a functioning pre-amp - you have to bypass the functioning pre-amp to see if it's doing what you want.

But ghken has a fairly high-end set-up, and may well have had it installed for some time. If his pre-amp has been progressively biting the big one, it explains his observations, and it's easy to test. Make sense?

Frank
I hear you, but I'm not so sure your test "tells" us anything of value, cuz
nothing can reasonably be expected to "change"....yup, still no signal....

Also could be a degraded cable/connector on the VHF input to the preamp....
Still sounds like he needs to send a trained monkey up the mast....or drop it...

I've requested help on this forum many times in the past because I've had so much trouble with horrible reception in inclement, especially windy, weather. I'm surrounded by close, tall trees. I recently switched from an LG 3410A to a Tivo Series 3 box. No problems at all since the switch, but we'll see when the trees leaf out. Sometimes, apparently, some tuners just can't keep up.

Requesting any reommendations for upgrades and improvements as the members of the house have a desire to remain OTA Terrestrial antenna only viewing until or unless satellite offers "a la carte" programming...they just don't offer what I want and whole lot I don't.
Cable (Comcast) is not permitted out in these sticks from what I'm told by Embarq.

Any suggestions are much appreciated.

Antenna:
Radio Shack VU-110 @ 25 Feet.
High-quality double-shield Belden RG-6 coax.
Rotor is disabled due to close lightning strike.

Antenna feeds (2) television sets using RadioShack gold 4-way splitter.
1 - coax into splitter
1- coax to my TV
1 - coax to my VCR
1 - coax to kitchen TV

*Recent purchase of Philips DVDR3575H/37 with ATSC tuner and amplified splitter
will allow the elimination of 4-way splitter to 2-way.
1 - antenna coax into splitter
1 - coax to Philips 3575 then to TV
1- coax to kitchen TV
0 - coax to VCR

Would using two coax downleads running to each TV be better than using a splitter?
If the answer is no, then is the R-Shack splitter as good as any?

As you can see my channel selection, only 2 channels will be VHF and the PBS will be VHF channel 3 and 13 will remain 13 (only digital).

I was hoping to eliminate VHF after the digital change and replace the old RS VU-110 with an improved UHF - only antenna. That is not to be it seems.

I would like to go with a Channel Master or Winegard "combo" antenna but with the straight elements versus the arrow or angled forward type.

I also want to replace rotor with new and better type. Any recommendations? My current dead rotor is a Genie? made by a garage door opener company that stopped making them.

I'm not sure if I need any amplifiers, but if it is recommended, then what type(s)?

My stations as listed by TVfool:
WDRL-DT 41 (24) Ind 18.1mi 247deg
WSET-DT 13 (13.1) ABC 21.6 mi 310 deg
W40BM 47 (32.1) 22.3 mi 358 deg
WWCW 20 (21.1) FOX 21.7 mi 311 deg
WSLS-DT 30 (10.1) NBC 46.9 mi 283 deg
WDBJ-DT 18 (7.1) CBS 47.3 mi 282 deg
WFXR-DT 17 (27.1) FOX 47.2 mi 282 deg
WPXR-DT 36 (38.1) Ind 47.4 mi 282 deg
OR
WDBJ-DT 18 (CBS)
WSLS-DT 30 (NBC)
WSET-DT 34 (ABC) moves to 13 during summer 2009.
WBRA-DT 03 (PBS)
WWCW-DT 20 (FOX) boosts power in February 2009.
WDRL-DT 41 (Unknown status) moves to 24 in February 2009.
WFXR-DT 17 (FOX)
WPXR-DT 36 (Ind/ION)

My Address with Lat/Long:
Address: 1010 Chellis Ford Rd
Lynch Station, VA 24571 [physical location is Leesville. Lynch Station is a post office 7 miles away]
(37.113945, -79.398008)
Latitude37.113945 °
N 37 ° 6' 50.2"
37 ° 6.8367' (degree m.mmmm)
Longitude-79.398008 °
W 79 ° 23' 52.8"
-79 ° 23.8805' (degree m.mmmm)
(37.11469533281682, -79.39821481704712)

fbov and Falcon_77,

I tried your website for the zip code 74112 (Oklahoma), and found it similar to one that I used at antennaweb.org, but got somewhat differing results. I guess that is to be expected though, because of variables and the accuracy of the information that they use. In any case, I should be receiving alot more stations than I do. I'm going to play with my current antenna some more to see if I can improve it. At least I want to get at least 1 or 2 digital stations so that I can know that the tuner works. It may just be my location, because my upstairs neighbor gets alot better reception than I have...at least on analog stations.

The only reason that I bought this particular tuner is because my other tuner doesn't have a XP x64 driver (PVR 150), and that is my preferred OS. I just received my flat coax to run through the patio door, so I will see what happens when I put the antenna on the patio.

EDIT: I noticed that neither website's output was based on the type of antenna used (directional, multi-directional, analog, HDTV, etc.) and that is the main thing that I was looking for...something to base a purchase decision on.

A lot of posters on these forums seem to like the Channel Master 9521 rotor. Good place to see the specs and all is Solidsignal.com.

RadicalRik: A Preamp should help quite a bit.
A "typical" installation could see a 10 dB improvement in sensitivity,
if nearby stations do not cause desensitization problems.

WDRL-DT will be only 9.6 miles away (Post-Feb2009) and Analog KTLU (CH50)
is only 6 miles away and might increase power in the future.

Hence it would be advisable to avoid hi-gain preamps (e.g. CM-7777) and use a lower gain,
high overload preamp such as W-G AP-8700 (SolidSignal.com, SummitSource.com, et al.).
The overall difference in sensitivity between preamps would be small anyway....

I played with the antenna some, and now I pickup a couple more channels than before, including 3 digital stations, but only one of them displays. It's picture is almost as good as cable, except that the signal strength varies and when it drops low the picute and sound stutters. Analog stations are nothing to brag about in terms of picture quality, but at least they are stable.

I'm trying to determine if the problem is more with the antenna, or with the display software...I suspect both. I think that the first thing to do is to get a better antenna, but I'm still lost on how to choose the best for my circumstances.

I have also been wondering if BeyondTV works with all tuners or not? I've run into a number of things that I know are display software related.

fbov and Falcon_77,

I tried your website for the zip code 74112 (Oklahoma), and found it similar to one that I used at antennaweb.org, but got somewhat differing results. ...

EDIT: I noticed that neither website's output was based on the type of antenna used (directional, multi-directional, analog, HDTV, etc.) and that is the main thing that I was looking for...something to base a purchase decision on.

The value of TVFool over Antennaweb is the signal estimate it calculates based on transmitter power and local topography. Just throwing in your zip, I see you should get 10-12 stations with rabbit ears/loop antennas. From your initial post, I assume you're not, and that means you may need to input your actual address.

Here's why.

I live 6.9 miles from my transmitters and I usually give TVFool the lat/long of my antenna, but street address is very close. My local testing indicates TVFool signal estimates are accurate, both for how powerful an antenna I need and relative reception, best to worst.

However, if I just put in my zip code, it's off by 30 dB, across the board because I live in a local low spot - a 99.9% error due to inputing an inaccurate address. I suspect something similar is happening to you; perhaps it's the building (won't be estimated) or a landscape feature (will be estimated) that's reducing your signal, because small indoor antennas should work at the post office.

Since you want an antenna recommendation, I've also looked at your post-transition spectrum, which will include current digital 10, plus Ch 8. This complicates things - you need both UHF and VHF reception. One good choice that's likely to fit on your balcony and receive the stations you want is the Channel Master CM-4228, a ~$50 antenna that's a top UHF antenna and a good VHF-high choice. I'm using a clone of it's little brother (CM-4221, ~$25) and all stations are 90+ on my TV with it in the attic. Then again, if rabbit ears can get your VHF channels, a CM4221 might be all you need. Here's a link:
http://www.warrenelectronics.com/antennas/4228.htm

While this ones big (36x40) it's flat; the next best recommendation is a combo VHF/UHF that's much longer and so not well suited to your patio.

I'll also note that digital tuners can be hard to use when aiming at a weak station. You'll likely have to input the real channel and then adjust antenna direction to see if you can get a lock. If you can, there's usually a signal display you can maximize. The trick is getting that initial lock.

Hope this helps,
Frank

[QUOTE=Rick0725;13449562]The ap 8700 would be a risk in regards to overload with the stations below and the splitting arrangment described. Would rather not take the chance and select the winegard hdp269 preamp instead.



Have had lots of issues with the HDP-269 preamp with strong local FM stations as it has NO FM trap. Need to be aware of this for certain areas. If there is no local FM that you know of than this is a good choice, or you may have to add an external FM trap if you do have one.

I use deep notch fm barrel filters when there are fm issues prior to the antenna input of the hdp269. The fm filters in most preamps are inadequate anyways for troublsome situations.

There are 3 large filter companies in town so I am lucky in that regard.

About $16.



If you have no need for low band (2-6) using the high port of a hi/lo combiner also works well. About 2-3 dollars each the last I checked.
http://www.picomacom.com/specs/pico/C/C24.pdf

The value of TVFool over Antennaweb is the signal estimate it calculates based on transmitter power and local topography. Just throwing in your zip, I see you should get 10-12 stations with rabbit ears/loop antennas. From your initial post, I assume you're not, and that means you may need to input your actual address.

Here's why.

I live 6.9 miles from my transmitters and I usually give TVFool the lat/long of my antenna, but street address is very close. My local testing indicates TVFool signal estimates are accurate, both for how powerful an antenna I need and relative reception, best to worst.

However, if I just put in my zip code, it's off by 30 dB, across the board because I live in a local low spot - a 99.9% error due to inputing an inaccurate address. I suspect something similar is happening to you; perhaps it's the building (won't be estimated) or a landscape feature (will be estimated) that's reducing your signal, because small indoor antennas should work at the post office.

Actually, I ran it both ways...by zip code and by address.


Since you want an antenna recommendation, I've also looked at your post-transition spectrum, which will include current digital 10, plus Ch 8. This complicates things - you need both UHF and VHF reception. One good choice that's likely to fit on your balcony and receive the stations you want is the Channel Master CM-4228, a ~$50 antenna that's a top UHF antenna and a good VHF-high choice. I'm using a clone of it's little brother (CM-4221, ~$25) and all stations are 90+ on my TV with it in the attic. Then again, if rabbit ears can get your VHF channels, a CM4221 might be all you need. Here's a link:
http://www.warrenelectronics.com/antennas/4228.htm

While this ones big (36x40) it's flat; the next best recommendation is a combo VHF/UHF that's much longer and so not well suited to your patio.

the problem with these antennas is that my apartment manager is very picky. When I discussed this with her, I was read the riot act, therefore, I want something less conspicuous.

I'll also note that digital tuners can be hard to use when aiming at a weak station. You'll likely have to input the real channel and then adjust antenna direction to see if you can get a lock. If you can, there's usually a signal display you can maximize. The trick is getting that initial lock.

Hope this helps,
Frank
I have about decided that the viewing software is half of the problem, because I tried using BeyondTV, and it made alot of difference...at least during the scanning of the channels. Unfortunately, I'm having a problem getting BTV working properly.

I think that it may take both items to make things right...antenna and software. As far as the antenna goes, I have been looking at some of the small multi-directional ones, so that I won't have to readjust the antenna every time that I change the channel. Even that wouldn't be so bad if it had an electric roter, but I have seen very few such critters. I understand that this kind of antenna would have less performance than a directional antenna, but judging by what I saw on BTV's channel scanner using just my rabbit ears, it may be enough.

Re: TVFool, can I assume zip and address gave similar results?

Re: picky apartment managers, see"
http://www.fcc.gov/mb/facts/otard.html
"The rule applies to individuals who place antennas ... on property that they own or rent and that is within their exclusive use or control ... such as a balcony or patio ..."

OTARD - over the air reception devices - is a congressionally mandated FCC rules that defines, among others, antenna rules for renters. If you follow the rules, your apartment manager is bound by it. Better not to make an issue, however, unless truly necessary.

Re: tuners, if that's the real issue, then try a good, small or indoor antenna. You may not need much more signal. Here's a good comparison:
http://www.hdtvprimer.com/ANTENNAS/comparing.html

Since there's a lot of information there, let me point to some highlights. The CM4228 is "A" in the UHF plot and at the top of the heap. Your rabbit ears are "J", small indoor loops (rabbit ears are a VHF antenna, "G" in the VHF plots). As you can see, there are a LOT of choices in between. The Silver Sensor (I) is an indoor antenna with a bit more gain, or you can get a small outdoor antenna and use it indoors. The CM4220 (not shown) is a 2-bay bowtie version of a 4228 array, as is the DB-2 (L). Both are similar to the Double Bowtie (K), but physically larger and so higher gain, and without legs. If used without their reflector, they become bi-directional, potentially satisfying your directional needs at the cost of much of their gain.

By the way, with a patio antenna, aren't you the rotor?

Frank

Thanks for the input so far. I didn't get a chance to play with it over the holiday weekend but will get back to it after the out of town guests leave tomorrow. I will try bypassing the preamp and see what that shows.

Here's a couple of additional points. The problems with VHF 7 started when I started swapping antennas, which required me to open up the CM7777 and switch it to the separate UHF/VHF input setting. When I noticed the drop in VHF 7 signal with the new antennnas and CM7777 configuration, I put everything back the way it was - the old RS antenna with the CM7777 switched back to combined VHF/UHF input. Signal for VHF 7 was still bad and all the various combinations I've tried since then hasn't brought it back to where it used to be.

I've always suspected the preamp to be the leading suspect, but it didn't make sense that only VHF 7 would be affected. I have two other stations broadcasting on VHF - 2 and 11 - that come in at the same level as they always have. I figured if the VHF section of the preamp was going bad then all 3 stations would be impacted.

Hi folks, I just thought I'd share this latest monsterpiece I built.
http://s167.photobucket.com/albums/u159/donnyjaguar/?action=view&current=e051b622.pbw
Its a remote switch to take my UHF preamplifier out of the loop and also has a switchable 20dB attenuator on the input from the antenna. Too cold to install just yet, but works fine in the workshop. I'm optimistic this will lend another level of versatility to my OTA setup.

I got the idea from my DISEqC switch on my satellite system.

DJ

I know CM makes a UHF only 75 ohm pre-amp, but they do not have any 300 ohm input UHF only pre-amps.

Does anybody know of a source for UHF only 300 ohm pre-amps / amplifying baluns?

Thanks,

~ryan

ghken,
As I now understand it, you upgraded from the RS VU-75 combo to a YA1713 and CM4221 and had to switch the 7777 to use both UHF and VHF inputs. At that point, you noticed Ch 7 WOOD-DT signal had dropped (the opposite of your expectation) so you put everything back, but WOOD-DT was still weak.

Process of elimination would say you did something to the pre-amp at the initial changeover. The bypass test should tell for sure. Just guessing, but how's the FM trap set?

Frank

Hi folks, I just thought I'd share this latest monsterpiece I built.
http://s167.photobucket.com/albums/u159/donnyjaguar/?action=view&current=e051b622.pbw
Its a remote switch to take my UHF preamplifier out of the loop and also has a switchable 20dB attenuator on the input from the antenna. Too cold to install just yet, but works fine in the workshop. I'm optimistic this will lend another level of versatility to my OTA setup.

I got the idea from my DISEqC switch on my satellite system.

DJ

Your workshop test.....did it include the antenna being hooked up and reception with a TV? I'm curious because at UHF frequencies, subtle issues like the routing of wires can affect operation. Also....I look and look at the photos, but just cant seem to see the vacuum tubes that are in the first schematic! ;-)

Re: TVFool, can I assume zip and address gave similar results?

Yes.


Re: picky apartment managers, see"
http://www.fcc.gov/mb/facts/otard.html
"The rule applies to individuals who place antennas ... on property that they own or rent and that is within their exclusive use or control ... such as a balcony or patio ..."

OTARD - over the air reception devices - is a congressionally mandated FCC rules that defines, among others, antenna rules for renters. If you follow the rules, your apartment manager is bound by it. Better not to make an issue, however, unless truly necessary.

I agree about not making an issue of it, but that OTARD link is interesting. One thing that I remember when discussing this with the apt. manager, is that they require proof of insurance, naming them, so that if someone gets injured by flying or falling antennas, they are covered. somehow, I think that might fall under the OTARD provision for unreasonable expense.

Re: tuners, if that's the real issue, then try a good, small or indoor antenna. You may not need much more signal. Here's a good comparison:
http://www.hdtvprimer.com/ANTENNAS/comparing.html

The reason that I'm wanting an ourdoor antenna is because when I place the rabbit ears outside on the patio table there is a significant improvement. I think that there is something about the construction of the unit that is interfering with reception.

Since there's a lot of information there, let me point to some highlights. The CM4228 is "A" in the UHF plot and at the top of the heap. Your rabbit ears are "J", small indoor loops (rabbit ears are a VHF antenna, "G" in the VHF plots). As you can see, there are a LOT of choices in between. The Silver Sensor (I) is an indoor antenna with a bit more gain, or you can get a small outdoor antenna and use it indoors. The CM4220 (not shown) is a 2-bay bowtie version of a 4228 array, as is the DB-2 (L). Both are similar to the Double Bowtie (K), but physically larger and so higher gain, and without legs. If used without their reflector, they become bi-directional, potentially satisfying your directional needs at the cost of much of their gain.

Aren't some of the small multi-directional anatennas an improvement over the rabbit ears? Radio Shack and one other company have ones that look like large frisbees. Some others that I have seen look like plastic pipes...are these any good?

By the way, with a patio antenna, aren't you the rotor?

I suppose that would be true with most people, but I'm lazy.

ghken,

Process of elimination would say you did something to the pre-amp at the initial changeover. The bypass test should tell for sure. Just guessing, but how's the FM trap set?

Frank

Frank, yes you understand my situation correctly.

I believe the CM7777 ships with the FM trap engaged, so that's how I had it when it was first installed with the RS antenna. When I was switching over to the Winegard/CM antennas, I did switch the FM trap off, thinking I might try using the antenna with my stereo tuner. I have since switched it back on and neither setting appears to noticeably change the signal level on VHF 7.

I connected a Philips DVDR-3575H/37 with it's ATSC internal tuner.
I can now receive most all of the digital channels and have an idea of reception quality which is pretty impressive for my 15 - 20 year-old *RS-VU-110 Yagi combo...
*to be replaced as soon as new antenna system is decided.

However, during installation of this component, I found that I am handicapping my already old and shabby antenna system with a 5-way splitter (or 4-way depending on how the antenna input is counted). That is, behind the TV is an RS gold splitter with antenna and 4 outputs. The unused one has a dummy load.

I currently feed and will continue to feed (2) TVs with my antenna (old and new). The splitter fed my TV, VCR and kitchen TV. The lead to the kitchen runs all the way from the back of my TV back to the basement and up to the kitchen. The splitter would be better in the basement in the spot where the cables could divide to come up to each TV (instead of doubling back for the kitchen TV).

Someone suggested to me perhaps a Channel Master "distribution amplifier" in the basement instead of a smaller 2-way splitter (downsized from my 4-5-way).
The antenna downlead would feed into the distribution amp, the off to each TV.

Is that a better solution for feeding two TVs off one antenna and cutting loss?

I'm sure someone else will speak up but, if you don't have to use an amplifer don't.
By going from 4way to 2 way splitter you've doubled the signal you had.
This may be enough.

... The reason that I'm wanting an ourdoor antenna is because when I place the rabbit ears outside on the patio table there is a significant improvement. I think that there is something about the construction of the unit that is interfering with reception.

Aren't some of the small multi-directional anatennas an improvement over the rabbit ears? Radio Shack and one other company have ones that look like large frisbees. Some others that I have seen look like plastic pipes...are these any good? ...


Buildings are bad for reception. For comparison, I've attached a link showing relative gain, outdoors and in an attic (not my work). Note the 15-20 dB loss. YMMV, but buildings are bad for reception, thus my initial question if your balcony faces any of the transmitter locations. I'd assumed it didn't, thus the big antenna recommended.

Antennas, while horribly complex at the detailed level, are pretty simple to first order. Since there's no free lunch, the only way to get gain - increase antenna output - is to become directional. Here's another HDTVPrimer link
http://www.hdtvprimer.com/ANTENNAS/types.html

While he uses "radiate" in place of "receive," they are equivalent.

Antenna geometry drives much of gain and beam width. He describes the difference between an isotropic and a dipole antenna, since it's a simple change and both isotropic and dipoles are used as a basis for comparison. The comparison link shows dBi (i for isotropic) on the left and dBd (d for dipole) on the right. That difference is worth +2.16 dB, a gain increase, and suddenly you have dead spots (nulls) you can aim at interfering stations just as you'd aim a gain peak at one you wanted.

Note that the dipole is still omni-directional in the plane perpendicular to the elements - its elevation plot is circular. That's wasted gain, unless you want TV from airplanes and your downstairs neighbor. 2-bay dipoles retain the directional (L/R) profile of the dipole but with increased gain due to a flatter elevation plot. A 4-bay gets even flatter - these bays stack vertically, so it's the vertical pattern (elevation plot) that changes. You can see the effect clearly in the links below - same directional pattern, very different elevation. Free gain, so to speak, by reducing gain in the vertical directions you can't use.
http://www.hdtvprimer.com/ANTENNAS/DB2.html
http://www.hdtvprimer.com/ANTENNAS/DB4.html

Some of the highest gain antennas availalble carry this one step further by adding a reflector - the large screen you see behind all the commercial multi-bay dipole antennas. This is what gives the commercial gain plots the characteristic directional shape you see at the bottom of the antenna types link, and in the DB2 and DB4 links above.

Here's a secret - you can take off the reflector. Now you're back to the fat-figure-8 dipole directional profile with it's two sharp nulls separating broad gain peaks.

I checked your TVFool plot and you do have strong stations 90 degrees apart; KGEB/KTPX are almost as strong as, but 90 degrees separated from your best stations. To get both groups, you'd aim inbetween; if one interfered with another, you'd aim the peak at one and the null at the other.

Two other neat things:
- the reflector is the most visible part, so removing it makes the antenna hard to see. (The flip side is that the dipole elements are an eye hazard.)
- You can test it for the price of 4 coat hangers and a 2x4.
http://www.avsforum.com/avs-vb/showthread.php?t=798265
(NOTE: this is a UHF-high design; increase 7" dipole spacings and wiskers to 9" for best reception of channels 14-52.)

Bottom line:
Omni-antennas have lower gain. If your balcony faces the transmitters, they'll work well, but so would a cheap directional. If your balcony faces away from the transmitters, omni's may not have the gain to receive through the building. A reflector-less 2- or (better yet) 4-bay dipole/bowtie would likely do as well.

I should mention the smart antenna. It uses multiple small antennas to synthesize a single, higher-gain antenna whose aim can be adjusted by the controller. You would need a compatible tuner, and can find out more - holl_ands just summarized a couple years' work.
http://www.avsforum.com/avs-vb/showthread.php?p=13461020#post13461020

Frank

Where's the attachment you ask? So do I!

... Where's the attachment you ask? So do I!


Here it is.

fbov,

After reading a comment earlier in this thread, I got to thinking that I could improve the signal strength to the tuner by disconnecting the TV and DVD player from the antenna. I had tried adding an amplifier, even though the rabbit ears are amplified, but instead of helping, the reception got worse...I don't really understand that.

In reference to your question regarding the direction that my patio faces, it is West, so the building only gets in the way of signals coming from the Eastern directions.

fbov,

After reading a comment earlier in this thread, I got to thinking that I could improve the signal strength to the tuner by disconnecting the TV and DVD player from the antenna. I had tried adding an amplifier, even though the rabbit ears are amplified, but instead of helping, the reception got worse...I don't really understand that.

In reference to your question regarding the direction that my patio faces, it is West, so the building only gets in the way of signals coming from the Eastern directions.

You're thinking in the right direction; we should have asked ... I'd assumed the antenna went straight to the tuner, which is not always the case. What do you get with only the tuner loading down the ears? Do you see any difference with the amp on/off (is it helping)?

A second (distribution) amplifier is not needed unless you have a long cable run or split the signal to many devices; you may have been overloading the tuner, or if you used a second pre-amp, overloading the second amp's inputs.

If your patio faces due West, 270*, an antenna on the railing (no overhang) might have line of sight (LOS) from about 190* to 350*. You'd have a chance at KGEB and KTPX LOS at 220*,but the majority are at 124*, so you're either receiving through the building (same as indoors), or catching reflections from farther downstream.

If you actually face SSW you'd be LOS to both. If you actually face NW, the buildings in the way for all of them. The true orientation matters, but based on your reports, I'm betting you really do get most stations through the building. No point in going outside if that's the case; a closet will do.

One last suggestion, then: Make a 4-bay coat-hanger bow-tie.

I suggested it in the last post, and referenced the link. I don't recommend the blogspot design without the stretch to 9", but this is very close to what's in my attic receiving signals (-70 to -78dBm) that are 30dB weaker than you get from the 124* antenna farm (-40 to -46 dBm).

You can use your current antenna for vhf and add a yagi style uhf antenna like a 91xg, mount them on a 5' mast spaced about 3.5' apart, combine the antennas with a pico uvsj vhf/uhf combiner then amplify with the hdp269. will cost you less than $100.

Most of my channels are in the UHF range and only 2 are in the VHF.
If separate VHF & UHF antennas are used instead of a "combo" then must the UHF be mounted above or below the VHF?

If the 2 VHF stations are in the same (magnetic) compass direction, then the VHF antenna can be aimed for best reception and no rotor is necessary.

However, if the bulk of the stations in UHF range are more spread out on the compass and even perhaps behind the antenna's directed aim.

Would it then be better to use an antenna such as a Channel Master CM4228 rather than an LX9 "corner Yagi"? Some antennas receive from a wider range of directions that others. The corner Yagi with the rear reflector keeps signals from the rear, if I read it right. A flat Yagi with it's elements is more directional than and array antenna? This part falls into the "beam width" of an antenna I suppose.

It would be nice to receive all of the channels (limited as they are) without a rotor.
A UHF that pulls in the "60 miles" (I know that claim means little or nothing) that receives from multi-directions versus an antenna that receives primarily what it is aimed at. I suppose I wondering if a CM4228 will pull in UHF stations the same distance as the LX9 but from a wider compass width?

Sorry for posting so many questions but I have one more...

I had asked before how I would go about hooking up an antenna in addition to a cable box, etc. to my TV that has only one coax input. I just saw something advertised for a coax splitter, however, that makes me curious--the splitter's advertisement lists under its "features":

"Versatile element: This splitter can split a signal from one antenna to two TVs or VCRs, or it can combine signals from two antennae to one lead-in."

So I was wondering--does this mean that I could hook this up in reverse, so that instead of splitting a cable signal to 2 TVs, I could combine the cable and antenna signal to one TV? That's what it sounds like to me but I wanted to know if anyone's aware of if it works, and how effective it would be?

Just to point out, I can't hook up my coax TV connection any other way because I'm in a dorm room, and thus there's no cable "box" just a jack in the wall to hook the TVs up to. Otherwise I'd just use a component hookup for that. Thanks for the help, yet again.

does this mean that I could hook this up in reverse, so that instead of splitting a cable signal to 2 TVs, I could combine the cable and antenna signal to one TV?Yes, you can use a splitter in reverse as a combiner. But, the problem with your installation is you would be combining cable and antenna, both of which would be using the same frequencies so it would be impossible to tune in OTA channel 13, for example, because there would be a cable channel 13 there. And, the OTA channel would likely cause problems with the cable channels as well, so you would loose the signal from both in a lot of cases.

So, bottom line is, it won't work.

Sorry for posting so many questions but I have one more...

I had asked before how I would go about hooking up an antenna in addition to a cable box, etc. to my TV that has only one coax input.

You need something like:

http://www.amazon.com/Parts-Express-Coaxial-A-Switch/dp/B0002ZPIQ4

You should be able to get it at Radio Shack.

It isn't automatic but it will do what you need it to do.

It would be nice to receive all of the channels (limited as they are) without a rotor.
A UHF that pulls in the "60 miles" (I know that claim means little or nothing) that receives from multi-directions versus an antenna that receives primarily what it is aimed at. I suppose I wondering if a CM4228 will pull in UHF stations the same distance as the LX9 but from a wider compass width?

Beamwidth typically narrows as forward gain increases. F/B ratio also increases in general with increasing forward gain and narrower beamwidth. There is no free lunch in other words. A better performing antenna for long distances will necessarily also have narrower beamwidth.

The 4228 is a very directional antenna.

Beamwidth typically narrows as forward gain increases. F/B ratio also increases in general with increasing forward gain and narrower beamwidth. There is no free lunch in other words. A better performing antenna for long distances will necessarily also have narrower beamwidth.

The 4228 is a very directional antenna.

Antenna beam-width is often simplified to only represent the azimuth plane, but the elevation plane needs to be considered as well.

For instance, the 4221 4-bay and the 4228 8-bay both have similar elevation beam-widths, but the azimuth beam-width on the 4228 is much narrower, due to how it's configured. It makes me wonder how a 2 vertical stack 4221 would perform.

Antenna beam-width is often simplified to only represent the azimuth plane, but the elevation plane needs to be considered as well. ...

I've made 2 4221-clones and planned to shorted their spines to make a cleaner 8-bay. Maybe I should retain enough spine length to align them stacked. In theory, you're right that the stacked aperture should have the tight elevation pattern of a stacked 16-bay
http://www.hdtvprimer.com/ANTENNAS/16bay.html
while retaining the broad azimuth pattern of a 4221.
http://www.hdtvprimer.com/ANTENNAS/cm4221.html

Unfortunately, I'm at least a couple weeks away from trying anything; still waiting for my coupon ...

Frank

After pondering and shopping a bit, I found a Radio Shack antenna that falls within my budget and space/location limitations, but from the reviews, I'm not sure that it would be a good choice. The most common cons were that it was flimsy and didn't last too long. Outside of weather/environmental factors, what makes an antenna last or not last? For something without any moving parts and simple design, it would seem that they should last forever, but with only a 90 day warranty, I'm sure that isn't true. At least it is directional, which everybody says is better, but would it still be so if set in the horzontal plane?

http://www.radioshack.com/product/index.jsp?summary=summary&techSpecs=techSpecs&currentTab=summary&custRatings=custRatings&features=features&accessories=accessories&productId=2348191&support=support&tab=features

Somewhere I've seen that antenna with the cover off, but I can't find the link. It's basically a dipole with some very creative element contouring, like a cross between a fractal diagram and a martial arts throwing disc. The only knock has been reliability; cheap electronics don't last in harsh environments. Judging by my Sears garage door opener, my garage is a harsh environment.

One thing, since it is directional, follow the install instructions. I bet a good fraction of purchasers miss that, aim it straight up, like many omni-domes, and wonder why it doesn't work.

fbov,

When you spoke about reliability, was that about this particular antenna, or just electronics in general? I had just about decided to mount the antenna indoors, because I assumed that the remarks that I read about it being flimsy had to do with it standing up in the wind. If it is strong enough to receive good signals indoors, that seems the way to go. The problem with that is that if it is attached to a wall, then it's direction can't be changed much, and since it is not bidirectional I will have to pick a wall that faces most of the channels, but not all.

I was making a general comment. I have no experience with this product.

Mounting indoors should increase it's lifespan, regardless. It comes with mast mounting hardware, so it's intended for a pole or J-mount. A wall mount would be fine as long as it was hinged, like a cabinet door; you will need to aim it. If you buy, try it out before installing; many times, antennas aren't returnable if they've been installed.

Thanks cpcat, Falcon_77 & fbov -
I have been spending a lot of time on the hdtvprimer site and reading about the different antennas and beamwidth etc...

In my situation for the Roanoke/Lynchburg, VA broadcast channels and their allotted channel frequencies, there are NOT many happy campers with what has been settled on.
Our PBS station [WBRA 15] will be assigned channel 3 which is low VHF. Our ABC station [WSET 13] will move back from UHF 34 to 13 post Feb 2009. That will leave us with two VHF channels and one of them low. The rest will remain broadcasting their digital in the UHF range.

According to TVfool using my longitude/latitude, my farthest station is in the 42 mile range (as are several others) up on one of the Blueridge Mountains.

I'm in sort of a valley (or downhill) if I'm standing on the front porch facing west. That is the direction of the mountains where the antennas are located and to which my TV antenna faces.

At my distance from the transmitters, VHF seems settled. Currently, I have a Radio Shack VU-110XR that is a combo VHF/UHF antenna with 10 elements (5-dipoles) and the corner yagi - 100" boom length @ 25ft.

I suppose the only decision left is for a UHF antenna... I notice that on both the CM4228 and the XG9, both have the ability to be aimed at the "skyline" On my current 'combo' antenna, the UHF is parallel to the ground (along with the VHF) at the house aiming at the center of the uphill grade.

My question concerns using a separate UHF antenna and aiming it at the skyline/horizon mounted 3.5' above a VHF antenna on the mast. Is this advisable?

I'm probably going to install a new rotor to replace my third frozen one that is currently up there because there is "no free lunch"

However, I am not antenna savvy enough to figure out which type of UHF antenna is the best choice: the CM4228 bowtie 8-bay array? OR the XG9 corner yagi? Angling either towards the skyline and rotating them, which would result in improved reception?

Azimuth and elevation beamwidths start to rise above my technical understanding... I had half-wave 80 & 40 meter dipoles in my HF amateur radio days and a vertical for everything above, but never the tower with the element yagis and loops and all...
I suppose that if i were able-bodied, I would experiment by building crude types of both and trying them out.

The xg91 and 4228 are pretty close overall for uhf. The main difference is that the 4228 will be much greater wind load and stress on your rotator. Decision made IMO. Put the xg91 or another equivalent yagi/corner reflector on the rotator above your vhf antenna.

I was making a general comment. I have no experience with this product.

Mounting indoors should increase it's lifespan, regardless. It comes with mast mounting hardware, so it's intended for a pole or J-mount. A wall mount would be fine as long as it was hinged, like a cabinet door; you will need to aim it. If you buy, try it out before installing; many times, antennas aren't returnable if they've been installed.
Since my last post, I ran over to the Radio Shack and bought it, but it is not the same as I had seen before. It is considerably thicker and heavier. The mounting hardware include a short mast which is bent at about 40 degrees and attaches to the base with a swivel of about 80 degrees. When I mentioned this to the saleman, he said that it was an older type, but I got the impression that he really didn't know anything about it.

As you suggested, I'm in the process of trying it out now, but I'm not having much luck with it. Although it is picking up more analog channels, it hasn't found but one digital channel, and that one isn't displaying. I vaguely recall reading a comment in a customer's review about locating the amplifier at least 6 feet from the antenna, but that means that I'm going to need another cable. What bothers me most, is that with either the rabbit ears or this dish, none of the channels...analog or digital are coming in with color...just B&W. I'm not sure if that is becaise of the antenna, tuner or software?

The xg91 and 4228 are pretty close overall for uhf. The main difference is that the 4228 will be much greater wind load and stress on your rotator. Decision made IMO. Put the xg91 or another equivalent yagi/corner reflector on the rotator above your vhf antenna.

Thank you cpcat! I needed that. I have been reading several pages back that some are not very happy with the XG91's quality (or rust and poor construction), but I suppose in I go with a Winegard VHF, I can also find a UHF that is the equivilent.

I was told that they need to be 3.5' apart (above/below). Can the rotor go below and rotate both?

The whole problem with my situation is the blasted VHF channels! I keep reading articles that the HDTV may all end up in the UHF range eventually even if they seem to have it all settled right now where they're going to land.

I appreciate your help. Perhaps, I should wait for a period and see how things settle...or the old RS-VU-110 falls down...

Thank you cpcat! I needed that. I have been reading several pages back that some are not very happy with the XG91's quality (or rust and poor construction), but I suppose in I go with a Winegard VHF, I can also find a UHF that is the equivilent.

I was told that they need to be 3.5' apart (above/below). Can the rotor go below and rotate both?

The whole problem with my situation is the blasted VHF channels! I keep reading articles that the HDTV may all end up in the UHF range eventually even if they seem to have it all settled right now where they're going to land.

I appreciate your help. Perhaps, I should wait for a period and see how things settle...or the old RS-VU-110 falls down...

You can aim the vhf independently from the uhf. Are the low and high vhf channels in different directions? If so, you might separate further using a lo/hi combiner allowing independent lo vhf and hi vhf antennas. Alternatively, you could rotate both the RS combo and the xg91 but again more stress on the rotator. If the lo/hi vhf channels are in the same location then just rotate the uhf.

The whole problem with my situation is the blasted VHF channels! I keep reading articles that the HDTV may all end up in the UHF range eventually even if they seem to have it all settled right now where they're going to land.

WHERE have you read an article saying DTV may quit VHF band????

The only thing I have heard is a proposal to extend FM band to CH6 and
maybe also CH5...which NAB will fight vigorously for many years to come:
http://www.tvtechnology.com/pages/s.0015/t.10139.html

In the L.A. thread, I SPECULATED that if NAB/MSTV are successful in beating
back White Space Devices (WSD) throughout the TV bands, the WSD guys
(Google, Microsoft, et.al.) may also make a run on the LOW VHF channels (CH2-6),
which are well suited for IP based protocols that can work through impulse noise.
[Why pay for 700-MHz channel, when they think they can use TV band for FREE....]

That would be a big shock to 43+ Lo-VHF and 427+ Hi-VHF Full Power broadcasters
(out of 1,400+ total) who have spent many megabucks for a "temporary"
UHF DTV station that must now be shut down as they spend megabucks to
upgrade their old VHF transmitter for DTV:
http://www.tvtechnology.com/pages/s.0001/t.1158.html#
BTW: This does NOT include statistics for more than 7,000 Repeaters & Low Power
transmitters who are not yet mandated to switch to DTV.....

You can aim the vhf independently from the uhf. Are the low and high vhf channels in different directions? If so, you might separate further using a lo/hi combiner allowing independent lo vhf and hi vhf antennas. Alternatively, you could rotate both the RS combo and the xg91 but again more stress on the rotator. If the lo/hi vhf channels are in the same location then just rotate the uhf.

Channel 3 (PBS) [VHF-low] from my Long/Lat 'ground-zero' is 19.1 mi. @ mag compass 286 deg.

Channnel 13 (ABC) [VHF-high] from my Long/Lat 'ground zero' is 42.1 mi @ mag compass 326 deg.

Not the same locations, but not too far apart? Not quite like one is behind me.

These (2) channels only remain VHS. Really cruddy how they're at opposite ends of the frequency spectrum huh? Would be nice to have been able to get either a VHF-low or VHF-high only antenna. A lot of complaints on the Roanoke/Lynchburg VA forum regarding Channel 15 (PBS) analog having to move down to 3 for their digital transmission....interference bigtime or no signal at all in digital, when they receive the analog 15 just fine.

All the rest: CBS, NBC, FOX, ION are all at the same location and distance as Channel 3 PBS. That is the antenna farm on Poor Mountain in the Blueridge for most Roanoke Stations. WSET 13 (ABC) is a Lynchburg station on Thaxton mountain.

I agree about stress on the rotor. If it were a case of VHF-high-only and UHF, there would be no problem... I may just have to go with another combo.
The RS-VU-110 does have to be replaced. It's 15+ years up there and I get effects and distortions from wind or rain or fog that I've never had. Channel 13 goes all rainbow on me and has been a ghosty analog station from the get-go...(not it's DT transmission though).
The RS-VU-110 has 10 VHF elements (or 5 dipoles) angled forward V-type and a corner yagi at the front.
Perhaps another combo from Winegard about the same length and elements, (only the straight elements)...perhaps slightly longer..

WHERE have you read an article saying DTV may quit VHF band????

The only thing I have heard is a proposal to extend FM band to CH6 and
maybe also CH5...which NAB will fight vigorously for many years to come:
http://www.tvtechnology.com/pages/s.0015/t.10139.html

In the L.A. thread, I SPECULATED that if NAB/MSTV are successful in beating
back White Space Devices (WSD) throughout the TV bands, the WSD guys
(Google, Microsoft, et.al.) may also make a run on the LOW VHF channels (CH2-6),
which are well suited for IP based protocols that can work through impulse noise.
[Why pay for 700-MHz channel, when they think they can use TV band for FREE....]

That would be a big shock to 43+ Lo-VHF and 427+ Hi-VHF Full Power broadcasters
(out of 1,400+ total) who have spent many megabucks for a "temporary"
UHF DTV station that must now be shut down as they spend megabucks to
upgrade their old VHF transmitter for DTV:
http://www.tvtechnology.com/pages/s.0001/t.1158.html#
BTW: This does NOT include statistics for more than 7,000 Repeaters & Low Power
transmitters who are not yet mandated to switch to DTV.....

I read a tech article on Google news awhile back about going digital for better or worse. It talked first about analog cell phones like my old emergency Motorola. Then, it talked about DTV and how the top guns were lusting after frequency spectrum for Homeland security and other needed purposes...blah blah blah...and pushing the powers that be to make immediate chage-over to all-digital before Feb 2009 in some areas. [That prompted me to order my coupons too early and they expire by May 29]

I read this while at the Wingard antenna site:

"The modulation system currently being used for DTV in the United States is Eight Level Vestigial Sideband (8VSB). As Terrestrial Digital / HDTV broadcasts become more prominent, UHF antennas will play a larger role because the majority of the HDTV/Digital channel allocations will be in the UHF frequency band."

I was overstating DTV. They seem to be indicting HDTV will want to be in UHF range. I must have focused on "majority"

I'm sorry if I mislead or got it wrong. I'm learning as I go and read. That is why I come here to be set straight on all things AVS

Channel 3 (PBS) [VHF-low] from my Long/Lat 'ground-zero' is 19.1 mi. @ mag compass 286 deg.

Channnel 13 (ABC) [VHF-high] from my Long/Lat 'ground zero' is 42.1 mi @ mag compass 326 deg.

Not the same locations, but not too far apart? Not quite like one is behind me.

.

Channel 3 is close to you and will be wider bandwidth reception typically. I bet you'll be ok aiming for 13 or just a shade to the left. Wait and see then make a change if necessary.

Channel 3 is close to you and will be wider bandwidth reception typically. I bet you'll be ok aiming for 13 or just a shade to the left. Wait and see then make a change if necessary.
I agree and thank you. I can wait awhile. I'm doing my research now, to then make my decisions, then my purchases of equipment and accessories, so that when work starts outside on the house and ladders are up, I'll have my antenna package ready to put up. It's easier when they're already up there painting the roof or scraping the side house for painting...

If PBS on 3 gets too much interference or lack of reception, complaints from those who receive fine analog, but no digital etc... they may have to move somewhere up the band if they're alowed. Everything else is between 13 & 36

I don't see anything on 15 for DTV. Too bad they could not just stay there at 15...though I don't know enough to answer the "why not" question.

With most VHF channels already being allocated to Analog, currently most
(but certainly not all) DTV stations were forced to operate in the UHF band.

There are only 12 VHF and 56 UHF channels, (shrinking to 38 UHF Post-Feb2009).
So by sheer force of numbers, most DTV stations will continue to operate in UHF band.

Everything else is between 13 & 36

.

If you truly only need uhf 14-36 then I've the perfect antenna for you:

http://cpc.farnell.com/AP00620/aerials-satellite/product.us0?sku=TRIAX-108791

It will outperform both the 4228 and the xg91 by a fair margin for channels 14-36 and will only be slightly more stress on the rotator vs the xg91.

There's some hassle/added expense with the overseas shipping etc. but worth it IMO. You need to order over the phone. You may also be able to find North American sources for band-specific antennas. Check here: http://www.wade-antenna.com/Wade/UHF%20Antennas.pdf

I can personally recommend the Triax. I have no experience with the Wade CYD series.

Since my last post, I ran over to the Radio Shack and bought it, but it is not the same as I had seen before. It is considerably thicker and heavier. The mounting hardware include a short mast which is bent at about 40 degrees and attaches to the base with a swivel of about 80 degrees. When I mentioned this to the saleman, he said that it was an older type, but I got the impression that he really didn't know anything about it.

As you suggested, I'm in the process of trying it out now, but I'm not having much luck with it. Although it is picking up more analog channels, it hasn't found but one digital channel, and that one isn't displaying. I vaguely recall reading a comment in a customer's review about locating the amplifier at least 6 feet from the antenna, but that means that I'm going to need another cable. What bothers me most, is that with either the rabbit ears or this dish, none of the channels...analog or digital are coming in with color...just B&W. I'm not sure if that is becaise of the antenna, tuner or software?

That short mast with a bend is the J-mount. It should allow you to mount to a number of locations and still aim.

The amplifier should be integrated into the unit; the box on the antenna line is a power supply, sending DC power to the amp through the coax. Its distance to the antenna doesn't matter under 100 yards. I'm assuming the coax plugs right into the antenna.

Let me do a quick checklist of what I guess you did to set this up.
- amp plugged in to AC
- coax line from amp to TV
- coax line from amp to antenna (both as labeled)
- antenna mounted vertically, like a pie plate on the wall
- antenna aimed roughly toward transmitter through minimal obstruction (window?)
- tuner set to known,strong digital channel in that direction
- antenna aim fine-adjusted to get a picture.

Comparisons with rabbit ears are useful. If it's not a lot better, exchange it (could be a malfunctioning unit);if it's still not better than $7 rabbit ears, return it.

As to B/W reception, the only reason I can see is if they're showing reruns of early Mayberry RFD or the original Outer Limits. The latter's opening sequence might mislead you initially ...

none of the channels...analog or digital are coming in with color...just B&W. I'm not sure if that is becaise of the antenna, tuner or software?Well, I've been receiving OTA from my fringe location for about 35 years now, and in the old days I used to have such a weak signal on occasion that I would get a very snowy picture with no color. With analog, the chroma part of the picture is on a slightly different frequency from the luminance, and the color required a considerably stronger signal than the B&W luminance. But digital doesn't work that way. I'm still receiving those distant stations now in the digital age, and when the signal is too weak (as it often is here), the picture pixelates (but still in color), or the screen is just blank. Maybe it's what fbov said.

You might try an old-fashioned free solution and see if that helps, since you aren't too far from the signal. I'm 14.4 miles from my stations, 1 edge. I just cancelled cable tv and while I figure all this out, I made a coathanger antenna which picks up channels 8+ fine. On analog currently I have 2 and 6, and when I get my converter I will have channel 4 digital until after the transition.

So I threw together a dipole antenna from old antenna wire, optimized to channel 4 (83"). I just split the wire down the middle until I got the right length, left it insulated except it had wire connectors on the ends already. I taped it to the back of a strip of painted 3/4" trim, which I tacked with a single finishing nail under my window, on a wall at approximate 90 degrees to the towers. It blends in with the window trim. I used really old balun and splitter/combiner, and the signal is crystal clear; unlike rabbit ears, it requires no adjustment. I waved the stick around a bit before I settled on a position. Currently upper VHF is 8,10,12 and those will be digital in 2009, but the coathanger antenna starts pulling in at channel 8, so I'm covered. Getting an antenna installed in 2009 may mean a bit of a wait, but towers and power are still moving targets, so I thought I'd wait and see. Here's the chart I used for wire length. My ~83" for my digital channel 4 solution picks up 2 and 6 analog, and helps out channel 8 a bit as well. After the transition, I may shorten it up a bit if I need help with 8/10/12.

http://www.kyes.com/antenna/rabbitear.html

You might try an old-fashioned free solution and see if that helps, since you aren't too far from the signal. I'm 14.4 miles from my stations, 1 edge. I just cancelled cable tv and while I figure all this out, I made a coathanger antenna which picks up channels 8+ fine. On analog currently I have 2 and 6, and when I get my converter I will have channel 4 digital until after the transition.

So I threw together a dipole antenna from old antenna wire, optimized to channel 4 (83"). I just split the wire down the middle until I got the right length, left it insulated except it had wire connectors on the ends already. I taped it to the back of a strip of painted 3/4" trim, which I tacked with a single finishing nail under my window, on a wall at approximate 90 degrees to the towers. It blends in with the window trim. I used really old balun and splitter/combiner, and the signal is crystal clear; unlike rabbit ears, it requires no adjustment. I waved the stick around a bit before I settled on a position. Currently upper VHF is 8,10,12 and those will be digital in 2009, but the coathanger antenna starts pulling in at channel 8, so I'm covered. Getting an antenna installed in 2009 may mean a bit of a wait, but towers and power are still moving targets, so I thought I'd wait and see. Here's the chart I used for wire length. My ~83" for my digital channel 4 solution picks up 2 and 6 analog, and helps out channel 8 a bit as well. After the transition, I may shorten it up a bit if I need help with 8/10/12.

http://www.kyes.com/antenna/rabbitear.html

If a person wanted to make a 1/2-wave dipole for channel 3 only and add perhaps a director and reflector (or two) is there a chart for the length of the aditional elements and haw far forward and behind the should be located?

I've seen antennas made with 1/2" PVC. The PVC is cut to length for either side of the dipole (cap for the ends), then a length of mast cut and a T fitting. Down the mast is fed 300 ohm "twin-lead" that is connected to either side of the dipole inside the T and then glued. At the bottom where the twin comes out the balun is connected to the twin lead and coax connected to that. Some have run a pieces of coax as the dipole arms inside the PVC and the shield (only) was used as the antenna.

I was wondering if a person had an old existing antenna and cut one pair of elements to channel 3 used as the active elements/ dipole, then left a pair of elements ahead and behind (director/reflector) and sawed off the rest of the front and rear of the mast... Would that make a good channel 3 only antenna?
The length of the reflector and director elements would need to be knoow though.

I'll have to leave your question to the smart antenna people around here. For channel 3, 91%(to correct for end effect) of 1/2 wave is 92" according to that link. But I don't know if it applies to antennas, or they have some way of combining length so you don't need the full half wave in one long rod. I guess I'll learn that if I stick around here.

Folded Dipole with Reflector and (optional) Director elements:
http://www.wfu.edu/~matthews/misc/dipole.html
After cutting the elements to proper length using chosen
wire sizes, you may need to tweak spacing to optimize gain.

Higher gain Yagi-Uda Antennas only cover a limited bandwidth,
about 1 channel in Lo-VHF, 3 channels in Hi-VHF and about
8-12 channels in UHF band. More info:
http://www.skyscan.ca/Antennas.htm
http://www.ifwtech.co.uk/g3sek/diy-yagi/
http://personal.ee.surrey.ac.uk/Personal/D.Jefferies/yagiuda.html
Be sure to read the ending paragraph in the above link.

Here's a followup on a problem I reported last week with an inexplicable loss of reception on one of my locals - WOOD-DT on VHF 7 in Grand Rapids, MI.

Up until this week, the only piece in the reception chain I hadn't swapped out was my preamp. So I picked up another CM 7777, hooked it up, and sadly the results were the same. :(

As a test I was asked to bypass the CM7777 altogether and see what happened. Well, going from antenna directly to my tuner I get zero reception on WOOD-DT and just barely pull in their analog on VHF 8. With it, there is a noticeable improvement in both digital and analog, but the digital has constant dropouts and is unwatchable.

So I'm left wondering what has changed. Even though this tower is about 40 miles out, I used to easily pull it in. Heck, I could even reliably get it using a homemade dipole I had cut for VHF 2 - mounted inside the attic!

The mystery remains. I have heard from a couple of other folks in the Grand Rapids forum with similar problems with WOOD-DT that started recently. The station has denied making any changes.

I'm left wondering if there is some interference coming in from outside markets. I imagine there are stations on VHF 7 in the markets surrounding me - Chicago/Milwaukee/Detroit/Traverse City.

Any other theories as to what/who the culprit is here? I sure don't want to have to start paying $$$ to Charter to get my HD locals.

I read this while at the Wingard antenna site:

"The modulation system currently being used for DTV in the United States is Eight Level Vestigial Sideband (8VSB). As Terrestrial Digital / HDTV broadcasts become more prominent, UHF antennas will play a larger role because the majority of the HDTV/Digital channel allocations will be in the UHF frequency band."

That was more true when it was written. We are 11 months away from a major shift back to VHF for DTV.

I don't know if this is possible, but I figure it won't hurt to ask.

I currently have an outdoor UHF/VHF combo antenna and mast-mounted pre-amp that is split 2 ways to my pc tuner cards in the 1st floor living room.

Now, I am wanting to add OTA reception to a 2nd floor room on the opposite side of the house. The outside of the house is already wired for all rooms for cable tv distribution (I have since dropped cable tv service). I know that if the signal from my antenna was strong enough, I could simply split the signal 2 ways and then hook it into to the two outdoor coax lines that I would be using.

It is when I consider adding a pre-amp that I get confused. My current setup requires that any splits in the signal occur after the power injector inside the 1st floor living room. In my case, there doesn't seem to be a practical way to split the signal inside and then run another cable up to the 2nd floor room.

My question is this: is there a way to amplify and then split the signal outside (near the antenna) so that I can send the amplified signal through the outdoor cable runs to both rooms?

I found another press release on the Direct Antenna's new products. The non-smart antenna units look interesting as well. But the press release contains more information on all the antennas including the smart antenna.
Press release Link (http://www.emediawire.com/releases/2008/3/prweb810554.htm)

No pictures on the smart antenna, it hasn't been designed yet, but there is pictures for the other two.
New Antenna Pictures (http://www.antennasdirect.com/index.html)

My question is this: is there a way to amplify and then split the signal outside (near the antenna) so that I can send the amplified signal through the outdoor cable runs to both rooms?The amplifier you now have should work OK for this, as long as any splitters you put between the mast mounted amp and the power injector are able to pass the DC current (most won't, but they make some that do). Your mast mount unit is where the amp is, so as long as you are getting power to it, it will still work.

The amplifier you now have should work OK for this, as long as any splitters you put between the mast mounted amp and the power injector are able to pass the DC current (most won't, but they make some that do). Your mast mount unit is where the amp is, so as long as you are getting power to it, it will still work.

Thanks for the quick reply. Does this mean that if I split the signal just after the mast mount unit (even though the power injector is at the end of the 1st cable run) the amplified signal will go to both cables? I assume you are talking about a 2-way splitter that is power passive on both ports?

Mloot,
Let me test my understanding. You have an outdoor antenna connected to 2 PC tuners. You also have an outdoor, cable TV feed to whole-house distribution. You'd like to hook the antenna up to the whole-house feed, but keep the PC feed.

What I'd suggest, assuming you have a splitter that will pass DC, is to split the signal out of the pre-amp, just as you describe, then put a distribution amp in the line to the whole house feed if the signal's too weak. Test it first - good splitters are only $6 - and only add the dist. amp if you get weak signal issues with the tuners you plan to use.

And since you'll be cutting coax and installing F-connectors, anything you can do to weatherproof the splitter and it's connections will only add to the longevity of the installation.

The one downside would be if you're marginal with the PC tuners now, adding a splitter upstream will drop their signal 3+dB (>50%). If that happens, a higher gain pre-amp ought to do the trick.

Frank

I'm left wondering if there is some interference coming in from outside markets. I imagine there are stations on VHF 7 in the markets surrounding me - Chicago/Milwaukee/Detroit/Traverse City.

Check with WPBN out of Traverse City to see if they made any changes. I'm surprised to see that WPBN and WOOD will both be on 7 next year for DTV operations. At only 110 miles from each other and with a non-directional antenna on WPBN, it could probably get worse in the summer months. WPBN's DTV transmitter on 50 was about 35 miles North, but they are moving back to 7 next year.

What do analog 7 and 8 look like? If you see any interference (other than snow) on 7, that may yield some clues.

I have a Chanel Master antenna in the attic. I am running the RG-6 down to the basement (about 70') and connecting it to a 8 way splitter. I have tried it with the amp, and without the amp.

The HDTV signals bounce from upper 80's down to the 30's, which makes watching a show difficult. Back when I had Comcast Cable, the digital cable would do the same thing. I would always end up unpluging the digital box and connect directly to the TV. I would lose a lot of the features, but at least I could watch without the freezing.

Is this more than likely the same problem? When I built the house I had my electrician put in two cable runs in a different attic (which I remembered after I put in the new run for the antenna). One, or both of these lines might be plugged into the splitter. There is one more cable plugged into the splitter than I have jacks throughout the house. Might this have something to do with it?
Josh

I hope I'm posting in the right place...

Since the main shows I care to watch are on OTA channels, I am considering getting rid of cable. I signed up and got a coupon (well two) for the digital converter box. After looking over some comments in AVS, I went with the Zenith DTT900. Now I need an antenna to connect to it. What kind of antenna would I need to receive the digital channels? Noting that "outdoor, higher, closer, bigger is better" is emphasized here, would a plain ol' set of rabbit ears not be good enough? What's the cheapest I can go on an antenna? At the very least, I've been able to determine that I don't need an "HD Ready" antenna (http://www.dtv.gov/consumercorner.html#faq12). Any help is appreciated.

What kind of antenna would I need to receive the digital channels?

It's impossible to say without knowing how strong the signals are at your location. This depends on how powerful the transmitters are, how far away they are from you, whether you're down in a valley or on top of a hill, etc.

Go to http://www.tvfool.com/ and enter your location (exact location is best). This gives you a table with information about the OTA signals at your location, as a PNG image. Save the image on your computer and attach it to a post here. Then people will have a clear idea of what you're dealing with.

Go to http://www.tvfool.com/ and enter your location (exact location is best). This gives you a table with information about the OTA signals at your location, as a PNG image. Save the image on your computer and attach it to a post here. Then people will have a clear idea of what you're dealing with.

Here ya go:

TVFool is showing very weak signals even though you are not too far from the TV stations. I guess large mountains are blocking the signals and you might get something from a reflection by pointing in the wrong direction. You could see if anyone in your area has had any luck by checking in the appropriate Local HDTV Info and Reception thread. You are probably going to have to keep cable.
John

Majik,
For grins, I threw your zip into MS's local.live.com; you're trying for Mt Wilson, the HARD way - from the end of the range, near Santa Clarita! This qualifies as deep fringe, but with a strong shift in channel assignments next year. Today, you need an antenna for ch 24-68. Next year, its ch 7 to 38. In both cases, since you can't get closer, you'll need bigger and higher because nothing indoor will cut it.

If you check out this link, you'll understand what I'll suggest. In all cases, it needs to be outdoors as high as you can get it, with a pre-amp on the mast and a rotor if you want more than Mt Wilson.
http://www.hdtvprimer.com/ANTENNAS/comparing.html (modeling based)
http://www.avsforum.com/avs-vb/showthread.php?p=6245872#post6245872 (empirical data, some of the same antennas as above)

Today, you need gain through Ch 68. The highest gain curves, labeled S, T and D, are for an 8-bay array and two Yagi's. These are premium antennas with excellent gain all-around, but they peak in the 60's, channel-wise and will set you back $100+. That makes an interesting tradeoff, since two different antennas, A and E, both 8-bay arrays, have better gain in the lower channels where you'll be after Feb. 2009, and they're a bit cheaper as well. The CM4228 has a lot of fans - look at it's VHF curve and you'll see another reason why.

After Feb. 2009, you also need VHF-high. You can add a dedicated VHF antenna for 7, 9 and maybe 13, or you can use a combo. Wineguard's got a new line of "HD" antennas that are really just VHF-high optimized VHF sections with a big UHF section. The Channel Master 3671B (marked "O") is the only UHF/VHF combo on the UHF charts. A dedicated pair (UHF and VHF) will absolutely work better than a combo, but at twice the price, it ought to!

The question is what you need. At minimum, a pre-amp is ~$50, a rotor another $70, the mast cost depends on height and anchoring options, maybe $30-300? Then you buy an antenna ($50-$250) and get it mounted on the mast. Cable TV starts looking better ...

Frank

Or go with a D* or E* satellite system...

That's got to be with WORST OTA reception situation I've ever seen......
Yup, you're in the Santa Clarita hole NW of Mt Wilson....
You might get a BOUNCE off mountains further NW or W of you.....maybe..

I have a Chanel Master antenna in the attic. I am running the RG-6 down to the basement (about 70') and connecting it to a 8 way splitter. I have tried it with the amp, and without the amp.
... There is one more cable plugged into the splitter than I have jacks throughout the house. Might this have something to do with it?
Josh

With a 70' run and marginal signal, my first question is what kind of amp? You want a mast-mounted pre-amp at the antenna to drive the signal down to the splitter, and perhaps a distribution amp in place of the splitter to feed the house.

Pre-amps have UHF or UHF/VHF inputs and one output, and they're powered through the coax by a separate power supply. They help tremendously when there's very little signal at the antenna, but they don't have enough gain to push through a lot of coax and splitters.

Distribution amps are 1-box units with one input and several outputs. As the name implies, they're designed to push signal over long runs to multiple locations, but without the pre-amp sending it a good signal, they have little benefit. It all starts at the antenna.

But it does matter where it ends; all ports must be terminated. A small screw-on cap is all you need to give un-connected ports the proper termination - if only I could think of their name ...

BTW, getting the antenna out of the attic may be the real solution. If you already have a functioning pre-amp at the antenna, and still can't get a lock connected directly (no STB or splitters) that's what's really needed. A good pre-amp will drive through 70' of coax easily, but it won't unless it had signal inputs in the first place.

Frank

Bummer....thanks!

I decided to move to this thread a conversation about antennas that had been started on another thread (ATSC Converter Box Comparisons).

I have a houseboat in Sausalito that has had trouble getting OTA reception; the location is at Liberty Dock, Sausalito, CA 94965.

My main goal is just to get access to television for emergency purposes after a disaster like an earthquake. I'm hard of hearing and can't understand radio communication, so I'd like to know if it's possible to receive OTA television after the digital transition. (Despite numerous requests, Marin County still hasn't come up with a system to send out emergency information via email at this time, so deaf and hard of hearing residents in the county don't have independent access to emergency information from the county if they have no access to TV.)

Most people who have houseboats in the harbor seem to use satellite or cable. However, I did see one house on shore with a massive arrangement of antennas.

dmulvany:
Northern Sausalito is maybe 10 miles, almost due North of Sutro Tower facility.
However, it's a double edge diffraction path. [Not over water....]
Indoor antenna may work.....I'm thinking reflections off hills N of you....
[Something the propagation prediction programs ignore.....]

But roof top VHF/UHF Combo would be better.

Thanks for looking this up, holl_ands. The peninsula that Sausalito is on is like a mountain range that's higher than the hills on the northern side (Tiburon). So it may be very difficult to get digital signals that are passing over that part of the peninsula (which I think is called the Marin Headlands).

The following picture is of a map from AntennaWeb which shows that the signals from the most useful stations would be coming across the high Marin Headlands.

http://maps.antennaweb.org/output/combined3_153171-db14028196463638.png

I've also attached an pdf file in case the URL doesn't work.

The most useful stations would transmit right over very high parts of the Marin Headlands (they're indicated by "F"). My best bet for getting any channel at all might be the NBC affiliate, channel 11, which at least would be better than nothing.

I'd appreciate any thoughts people would have about this, including whether I should get a CECB with a double conversion tuner or a smart antenna interface.

Dana

I decided to move to this thread a conversation about antennas that had been started on another thread (ATSC Converter Box Comparisons).

I have a houseboat in Sausalito that has had trouble getting OTA reception; the location is at Liberty Dock, Sausalito, CA 94965.
...
I'd appreciate any thoughts people would have about this, including whether I should get a CECB with a double conversion tuner or a smart antenna interface.

Dana

Dana,
First off, thanks for your efforts on the CECB threads; you fill a void no one else is covering. And I was going to suggest asking here ...

Antennaweb is of limited usefulness compared with TVFool.com. I've attached that site's output for Liberty Dock, for you consideration. It gets even better with the lat/long of your antenna site; this might be for the dock street level. In your case, I'd get as precise as you can.

If this is what you see on the water, you're not in bad shape. The San Jose stations at the top (127*) are at rabbit-ear signal levels, line of sight to the transmitters. These should be strong even if you lose LOS down on the water.

San Francisco is the challenge, but at signals in this analysis that are within rooftop antenna range. This is where the precise location is important as a few dB either way can make a difference. A big UHF antenna will get all the signals shown for Liberty Dock, and might even get VHF 7 and 12, post transition.

Bottom line: nothing's going to prevent you from getting San Jose even if you lose LOS, so you'll have PBS, Uni TEL and an independent. SF will depend on how accurate the TVFool predictions are for the dock vs. the boat. I suggest finding your long/lat at the boat and re-running TVFool. You may end up aiming at the hill crest, but I bet you can get something, if only 7 and 12, whose longer wavelengths should bend over the hills better.

As to antenna recommendations, I'd rather wait for a more accurate TVFool plot, since there's a chance you're out of luck at water level.

Hope this helps,
Frank

I've attached my tvfool results.

With a CM 4228, about 35 feet of cable, then a 4 way splitter, and then from 15 - 30 feet of cable to the 4 outlets I recieve WCVW (real 44, -113.2) and up with the exception of WWBT (real 54). All outlets seem to get the same results, even without the splitter I seem to have the same reception strength.

My question is...Is there an explanaintion for why I get drop outs more frequently on WTVR (CBS), and WRIC (ABC), while the weaker WCVW stays solid longer, unless we have heavy fog (like last night)?

(That raises another question, in the fog my analog reception last night looked much clearer, why is fog better for analog but not digital?)

I've spoken with someone in my area who lives at a much lower elevation, he is able to aviod dropouts on CBS, and he thinks it is from his 4221 stack. Should I go with one too?

Dana,
First off, thanks for your efforts on the CECB threads; you fill a void no one else is covering.

It's nice you think that! <grin> Other people have been very helpful, though, like holl_ands and smpowell, both of whom have been updating useful spreadsheets about the CECBs (and including information about digital closed captioning in them).

Antennaweb is of limited usefulness compared with TVFool.com. I've attached that site's output for Liberty Dock, for you consideration. It gets even better with the lat/long of your antenna site; this might be for the dock street level. In your case, I'd get as precise as you can.

I had tried TVfool.com before, but find it a bit difficult to understand. It's also been a bit difficult finding the exact latitude and longitude of the houseboat since the actual location doesn't correspond to the "street" location, and on one tool I used, Liberty Dock was mislabeled. I wish that the satellite version of Google (which clearly indicates where my houseboat is) could be used to find latitude and longitude. Regular map views don't show the houseboats. So I'm not absolutely sure I have the correct latitude and longitude for the houseboat, but I've gotten pretty close, I think.

If this is what you see on the water, you're not in bad shape. The San Jose stations at the top (127*) are at rabbit-ear signal levels, line of sight to the transmitters. These should be strong even if you lose LOS down on the water.

Those stations (PBS, Uni, TEL) don't transmit emergency news in English, however (as far as I know).


San Francisco is the challenge, but at signals in this analysis that are within rooftop antenna range. This is where the precise location is important as a few dB either way can make a difference. A big UHF antenna will get all the signals shown for Liberty Dock, and might even get VHF 7 and 12, post transition.

Bottom line: nothing's going to prevent you from getting San Jose even if you lose LOS, so you'll have PBS, Uni TEL and an independent. SF will depend on how accurate the TVFool predictions are for the dock vs. the boat. I suggest finding your long/lat at the boat and re-running TVFool. You may end up aiming at the hill crest, but I bet you can get something, if only 7 and 12, whose longer wavelengths should bend over the hills better.

If I could get NBC *and* ABC, that would be good for emergency purposes. If I could get only NBC using an indoor antenna, that might be okay as a back-up in case I can't use the satellite receiver (due to earthquake damage or some other reason). (I have a 20-inch HDTV that might be able to run off my portable power supply or a generator if I get one.)

As to antenna recommendations, I'd rather wait for a more accurate TVFool plot, since there's a chance you're out of luck at water level.


I'd be curious what the ballpark figure would be to get rigged up to get more channels (and how many channels I might be able to get), but the marine environment and the wind would also be tough on outside antennas.

Here are the pre-transition and post-transition digital channels for the houseboat:

It's also been a bit difficult finding the exact latitude and longitude of the houseboat since the actual location doesn't correspond to the "street" location, and on one tool I used, Liberty Dock was mislabeled. I wish that the satellite version of Google (which clearly indicates where my houseboat is) could be used to find latitude and longitude. Regular map views don't show the houseboats. So I'm not absolutely sure I have the correct latitude and longitude for the houseboat, but I've gotten pretty close, I think.

You can try web sites like http://www.earthtools.org/ to help you find more accurate coordinates for your location. You can select between the usual map or satellite views. Just keep zooming in until the cross-hairs in the center of the map are on top of the point you want to reference.

The coordinates are shown in the upper left hand corner of the screen. If you want a VERY accurate coordinate, you can click on the tab labeled "Location" just underneath. This will reveal the coordinates down to an excessive number of decimal places. Simply cut-and-paste the coordinates as needed.

Best regards,
Andy

You can try web sites like http://www.earthtools.org/ to help you find more accurate coordinates for your location. You can select between the usual map or satellite views. Just keep zooming in until the cross-hairs in the center of the map are on top of the point you want to reference.

The coordinates are shown in the upper left hand corner of the screen. If you want a VERY accurate coordinate, you can click on the tab labeled "Location" just underneath. This will reveal the coordinates down to an excessive number of decimal places. Simply cut-and-paste the coordinates as needed.

Best regards,
Andy

Andy probably as the better idea, but I wanted to suggest Google Earth. There's a status line at the lower left of the map that displays the coordinates, the altitude and apparent height above surface of the view where the cursor is pointed. Since it reads from the cursor position, cut & paste is out -- you have to transcribe the coordinates, but it is extremely accurate.

...It's also been a bit difficult finding the exact latitude and longitude of the houseboat ...

I use topozone.com. It can be hard interpreting topographic maps, but they give you 6 significant figures and you can read altitude off the contours.
Frank (gotta run!)

You can try web sites like http://www.earthtools.org/ to help you find more accurate coordinates for your location. You can select between the usual map or satellite views. Just keep zooming in until the cross-hairs in the center of the map are on top of the point you want to reference.



Thanks, Andy. Very helpful.

The Earthtools also looks useful for estimating the height of the "mountain range" between the houseboat and the TV transmitters to the south. 101, for example, goes through a tunnel, and the height of the mountain that it goes through is 672.6 feet (or 205 meters). That "mountain range" is about 2.1 miles southwest from the houseboat (and possibly in the way of the transmissions from San Jose). However, it depends on just where those TV transmitters are.

When I've walked out on the roof towards the northeastern end of the houseboat, I can see the eastern part of San Francisco when the other boats around are at low tide. I've never used an antenna on that part of the houseboat. Possibly using an antenna at the northeastern part of the houseboat would intercept the transmissions from San Jose better.

I've uploaded the TVfool pictures based on the more accurate latitude and longitude and from the northeastern part of the boat.

Looks like it will get easier to get ABC after the transition occurs.

You can try web sites like http://www.earthtools.org/ to help you find more accurate coordinates for your location. ...

Andy, great site; Google maps with a pointer.
(No where near TVFool, however)

Frank

Thanks, Andy. Very helpful.
...
I've uploaded the TVfool pictures based on the more accurate latitude and longitude and from the northeastern part of the boat.
...

According to Andy ...
"The most important value to pay attention to is the "Rx(dBm)" value since that is roughly how much signal you have to work with. ... in VERY ROUGH TERMS, signals above about -70 dBm should be strong enough to receive with an indoor antenna, signals above about -90 dBm should be strong enough to receive with an attic antenna, and signals above about -110 dBm should be strong enough to receive with a rooftop antenna."

I've only tested the -70 dBm recommendation and I was just UN-able to get stations weaker than -70dBm with an indoor antenna but get them very well with an attic antenna. The key was that he correctly predicted the hole I live in and it's affect on signal.

In your case, most of the plot is in the -90 to -110 range, so it predicts that a good rooftop antenna will do the trick. I can specifically recommend the Channel Master 4228 as it's a proven design with high UHF gain AND enough VHF-high gain that you will not need a separate VHF antenna, post-transition.

I've attached some test data Bob Chase posted (Thanks Bob!) that compares this unit with several high-end UHF and a range of VHF antennas. Only two do very well across the 7-52 channel range. The CM 3671 is a monster of a dual-element antenna roughly the size of a car, but it gets Ch 2-6 as well ...

Costs are roughly $50 for the 4228, $50 for a UHF/VHF pre-amp, a rotor's another $70 but you may be able to do that manually (Or aim this at SF and ignore SJ). Cable's fairly cheap using vendors in the AVS header. Shipping won't be trivial as the 4228's not small (40"x36"x4"), but the place I recommend below will combine items to keep it down (especially poles).
http://www.warrenelectronics.com/

With -90 to -110 signals with no mast height specified, you should be good. A smaller antenna might work, but not for both VHF and UHF. Just be prepared to aim at the hill crest, as that's where the signal if strongest, not toward the transmitters behind it.

Good luck,
Frank

According to Andy ...
"The most important value to pay attention to is the "Rx(dBm)" value since that is roughly how much signal you have to work with. ... in VERY ROUGH TERMS, signals above about -70 dBm should be strong enough to receive with an indoor antenna, signals above about -90 dBm should be strong enough to receive with an attic antenna, and signals above about -110 dBm should be strong enough to receive with a rooftop antenna."

I've only tested the -70 dBm recommendation and I was just UN-able to get stations weaker than -70dBm with an indoor antenna but get them very well with an attic antenna. The key was that he correctly predicted the hole I live in and it's affect on signal.

In your case, most of the plot is in the -90 to -110 range, so it predicts that a good rooftop antenna will do the trick.

What would be recommended for an attic antenna in order to get the NBC (-82.6, 2Edge, 164 degrees) and ABC (-72.6, 1Edge, 162 degrees) stations post-transition? (I have some limited attic space, maybe about 3 or 4 feet high, at the northeastern side of the houseboat.)

(Because of how close together and exposed the houseboats are, very large outside antennas if used frequently would make a negative impact in the look of the area, and I'd probably use the satellite receiver most of the time anyway. My main interest is in getting emergency news from local stations like ABC and NBC as a back-up in case I can't use the satellite receiver, and if I can do that using an inconspicuous attic antenna, so much the better. )

(The CBS station is at 91.1---very close to the cut-off; if I could get that as well, that would be nice, but not a deal-breaker.)

When you suggest aiming at the hill crest, are you talking about angling the antenna to optimize reception rather than using a straight up and down vertical orientation?

My late father, who had owned this houseboat, had set up an odd-looking external antenna on a wheel, but it isn't angled up towards the hill crest and didn't get very good reception. When I get out to the houseboat again, I'll take a picture of it so you can all look at it and scratch your heads! Maybe if it was angled better, it might work a lot better.

I've been testing a homemade Gray-Hoverman UHF antenna, and folks, this antenna really works well. I can receive all 10 Oklahoma City UHF digital stations from about 70 miles away with very few breakups, with the antenna only six feet off the ground. This is with the antenna connected to one tuner only, reception drops somewhat when the signal is split to two tuners.

I'd like to build a sturdier one to mount in my attic along with a VHF-Hi antenna, connect these through a pre-amp and combine the OTA signals with the RF outputs from my two satellite receives for distribution throughout the house. I hope this drawing will make clear my setup, and what I want to do.
106482
The unused terminal on the 4-way splitter is currently terminated, but is reserved for possible diplexing with the satellite antenna feed to the lower left TV. The satellite RF outputs don't presently need any amplification for whole-house distribution. The Sat/DVR box on the right has a built-in ATSC tuner. The black lines are my present setup, with the red indicating what I'd like to end up with. Satellite antenna feeds are separate cables not shown on the drawing.

Is there a better way to go about this? I'm considering using a CM 7777 pre-amp, will I also need a distribution amp? All cable runs are between 25 and 55 feet, with the longest path from the antenna to any TV being less than 70 feet. Will a pre-amp prevent the broadcasting of the satellite box outputs, or is something else needed?

Thanks in advance for your comments.

What would be recommended for an attic antenna in order to get the NBC (-82.6, 2Edge, 164 degrees) and ABC (-72.6, 1Edge, 162 degrees) stations post-transition? (I have some limited attic space, maybe about 3 or 4 feet high, at the northeastern side of the houseboat.)

With KNTV/NBC's booming power of over 50kW in your direction (which is quite high on DTV VHF), I think we are putting too much thought into this. Even with 2 edge reception, I wouldn't be surprised if you can pick this up with simple rabbit ears.

If you end up installing a VHF antenna in the "attic," something like this should be fine:

http://www.solidsignal.com/prod_display.asp?prod=Y5-7-13

What would be recommended for an attic antenna in order to get the NBC (-82.6, 2Edge, 164 degrees) and ABC (-72.6, 1Edge, 162 degrees) stations post-transition?
...
When you suggest aiming at the hill crest, are you talking about angling the antenna to optimize reception rather than using a straight up and down vertical orientation?

My late father, who had owned this houseboat, had set up an odd-looking external antenna on a wheel, but it isn't angled up towards the hill crest and didn't get very good reception. When I get out to the houseboat again, I'll take a picture of it so you can all look at it and scratch your heads! Maybe if it was angled better, it might work a lot better.

Dana, same recommendation, maybe.

Conventionally constructed attics are worth -15 to -20dB signal loss; Bob Chase tested that, too, attached. Those stations should still be receivable with a CM-4228 antenna (Can't see you attachments while replying.) and conventional construction, but this is a house boat. If it's all wood construction, there's no issue. If it's all metal, you'll have to mount outside.

If, however, these ABC and NBC stations are the VHF-high stations you'll have post-transition, and they're all you need, Falcon_77's recommendation is a better choice. It's form factor may also be easier to mount - long-and-wide vs. tall-and-wide for the 4228 - depending on the shape of the attic space.

I'd thought about suggesting a "use-in-emergency strategy," to address corrosion and visual clutter - find where it works, then store it until you need it. Attic mounting is perfect, if it works.

Angling the antenna is what you think. All antennas have a peak gain direction, and the higher the antenna gain, the faster gain falls off as you move off that direction. In a marginal case, after adjusting L/R, I'd try tilting back to see if signal improves. The last "edge" diffracting the signal is the effective source for your signal.

Pictures are always interesting ...

Frank

Well, I played around with 20' of pipe in the air and just made the plunge of ordering a NEW American 50' tower.

Holy cow, did these go up in price.

My dealer quoted me:

$550 - 5 Sections of tower (1 pc S-7 & 4 pcs S-5)
$120 - Concrete
$160 - Labor
$ 20 - House bracket
======
$850

My old system is in the attachment.

Any feedback?

The only issue with that is FINDING a VHF only antenna now - I have one - bought a couple of years ago.

Howdy neighbor (Scooper)!

Dumping the D*tv sat as of 4/15 and going strictly OTA. Tired of increasing prices with only shopping channels being added. Did a self-install on that one back in ’97 and bought my own triple LNB dish, Hughes HB-045 rec3eiver. It has worked flawlessly.

Anyway, below is list of equipment I have coming. The CM 3671 will be located on the chimney on a rotator.
I live in low spot west of US 1 and south of Hwy 96 with 40-60 ft trees around. I figured that there’s going to some hot channels and I’ll be picking up an inline attenuator (if needed, the SAT version). :confused:

Anyway, plugged up a Samy DTB-H260F to use now on my 480I 27” Phillips tube until I get the HDTV. Please don’t laugh, I have about 250 albums and a B&O turntable….gives you an idea how long I’ve been around. Jumpered the ‘Y’ component from the component out on the 260F to the composite video ‘in’ on the set to bring up the menus in B&W. Got 11 DTV channels with a 10dB powered rat shack rabbit ears for starters. One of the non-network stations on the 47 frequency (I think) had kids programming on….better picture than from my DVD player both using S-Video connections on the cartoon / puppet stuff.:D

Anyway, Scooper, I’d appreciate any comments you (or anyone else’s) may have and the equipment I’ve picked out since you live in the area and also is listed atennaweb.org’s information. About half the stations would drop out occasionally.:( The rabbit ears were located facing approximately 190º on the opposite side of the house last night.

The antenna will be about 25-30ft up and the closet neighbor's houses is greater than 75ft from the to-be mast location.
Once again, I picked the equipment listed because I’m in a low spot with large trees (mostly hardwoods) around on some of my land and the neighbors’ lands too. Also, the total RG6 will be 80ft to the great room. I plan to split the signal after the FM splitter and feed to a bedroom that is already wired…. Another 50 ft.

CM 3671
CM 7777
CM 9521A
Perfect Vision 2-way Splitter for Off / Sat (P7002AP)
Winegard CA8800 FM Band Separator/Coupler
(2) 5ft Galvinized Mast (CM1805)
CM 9067 Y-Type Chimney Mount
Single Grounding Block - One RG-6 Cable
Copper Grounding Rod (4 ft) - Pro Brand | Qty: 2
Perfect Vision ASA38 Copper Clamps 3/8 (ASA38) | Qty: 2
Copper Ground Wire #10 Gauge - 30 Ft | Qty: 1
Digicon RG6Q Connector Quad Shield Coax 6ft
Digicon RG6Q Connector Quad Shield Coax 25ft
Digicon RG6 Connector Coax Cable- 3ft (Qty: 2)

From Antennaweb.org

uhf WRAL-DT 5.1CBS RALEIGH, NC 190° 25.6 53 *yellow
uhf WRAZ-DT 49 FOX RALEIGH, NC 190° 25.6 49 *green
uhf WNCN-DT 17.1 NBC GOLDSBORO, NC 190° 25.6 55 red
uhf WRPX 47 ION ROCKY MOUNT, NC 87° 19.0 47 red
uhf WNCN 17 NBC GOLDSBORO, NC 190° 25.6 17 *red
uhf WLFL-DT 27 CW RALEIGH, NC Feb 17, 2009 (p-t) 189° 25.6 27 *red
uhf WRDC-DT28.1 MNTDURHAM, NC 189° 25.6 27 red
uhf WLFL 22 CW RALEIGH, NC 225° 28.1 22 *red
uhf WLFL-DT22.1 CWRALEIGH, NC 189° 25.657 *red
uhf WRDC-DT 28 MNT DURHAM, NC Feb 17, 2009 (p-t) 189° 25.6 28 *red
vhf WTVD-DT11.1 ABC DURHAM, NC Feb 17, 2009 (p-t) 190° 26.0 11 red
uhf WRDC 28 MNT DURHAM, NC 190° 25.4 28 red
uhf WRAY 30 SAH WILSON, NC 134° 25.7 30 red
vhf WRAL 5 CBS RALEIGH, NC 191° 25.4 5 *red
uhf WTVD-DT 11.1 ABC DURHAM, NC 190° 26.0 52 red
uhf WRAZ 50 FOX RALEIGH, NC 191° 25.4 50 red
vhf WTVD 11 ABC DURHAM, NC 190° 26.0 11 blue
vhf WUNC 4 PBS CHAPEL HILL, NC 260° 38.0 4 *blue
uhf WRAL-DT 48.1 CBS RALEIGH, NC Feb 17, 2009 (p-t) 189° 25.6 48 *blue
uhf WNCN-DT 17.1NBC GOLDSBORO, NC Feb 17, 2009 (p-t) 89° 25.6 17 blue
uhf WUVC 40 UNI FAYETTEVILLE, NC 224° 44.7 40 *blue
uhf WRPX-DT 15 ION ROCKY MOUNT, NC 87° 19.0 15 blue
uhf WUNP 36 PBS CHAPEL HILL, NC 75° 41.9 36 *violet
uhf WRAY-DT 42 SAH WILSON, NC 134° 25.7 42 violet
uhf W64CN 38 TBN RALEIGH, NC 191° 25.4 38 *violet
uhf WUNC-DT 4.1 PBS CHAPEL HILL, NC 260° 38.0 59 violet

I'm still reading this tread......

Lukes,
If you're still reading, click one of the TVFool.com links and post the .PNG (both today and post-transition) as an attachment tomorrow, after your obligatory 5 (?) posts. Antennaweb is missing a key response - signal level - and is notorious for missing fine details like the low spots you and I live in (but it misses trees and houses). Street address is good, long/lat is better, both truncated in the plot for your privacy.

You've picked a top-line set-up; I bet you realized that TV reception's the same, NTSC or ATSC so everything you know still applies. The only issue I see is tuner overload if you have a close/strong station, and the closest station I see is still 19 miles.

When you get it up, let us know how you fare. The 3671 is one of the few combo units that has a high-gain UHF section, and the H260 is well respected. If you think the puppets looked good, wait until you get a real HD image and display!

Frank

Well, I played around with 20' of pipe in the air and just made the plunge of ordering a NEW American 50' tower.

Holy cow, did these go up in price.

My dealer quoted me:

$550 - 5 Sections of tower (1 pc S-7 & 4 pcs S-5)
$120 - Concrete
$160 - Labor
$ 20 - House bracket
======
$850

My old system is in the attachment.

Any feedback?

Sounds pretty reasonable to me.Let me know if you want a big Highbander to put on it.

Let me pay off this tower, and you might have a deal! ;)

Sounds pretty reasonable to me.Let me know if you want a big Highbander to put on it.

Lukes,
If you're still reading, click one of the TVFool.com links and post the .PNG (both today and post-transition) as an attachment tomorrow, after your obligatory 5 (?) posts. Antennaweb is missing a key response - signal level - and is notorious for missing fine details like the low spots you and I live in (but it misses trees and houses). Street address is good, long/lat is better, both truncated in the plot for your privacy.

You've picked a top-line set-up; I bet you realized that TV reception's the same, NTSC or ATSC so everything you know still applies. The only issue I see is tuner overload if you have a close/strong station, and the closest station I see is still 19 miles.

When you get it up, let us know how you fare. The 3671 is one of the few combo units that has a high-gain UHF section, and the H260 is well respected. If you think the puppets looked good, wait until you get a real HD image and display!

Frank

I'm thinking I'm having to go large directional antenna and 'hot' with this setup because of being in a hole and the trees all around looking up to the horizon.

Not sure, but I think the Samsung DTBH260F HDTV Terrestrial Receiver will not be that sensitive, if so, I'll temporarily bypass the CM 7777 until I get the inline variable attenuator, if needed.

Am I correct in assuming that in most cases (signal level only) that I should be able to receive VHF signals > -90 dB and UHF > -70 dB??? A friend in Fayetteville, NC who installs video systems commercially for large hotels, etc, said that a -10 dB signal level is optimal at the receiver?

Am I correct in assuming that in most cases (signal level only) that I should be able to receive VHF signals > -90 dB and UHF > -70 dB??? A friend in Fayetteville, NC who installs video systems commercially for large hotels, etc, said that a -10 dB signal level is optimal at the receiver?

I would expect that you could get anything on your tvfool list that is stronger than about -93 dbm. VHF/UHF shouldn't matter. An aggressive antenna would pick up a few more analog LPTV stations. I wouldn't bother.

Your friend is using dbuv numbers. tvfool uses dbm. uv referes to microvolts in a 75 ohm system; dbm refers to milliwatts. The -10 dbuv preferred measurement is usually after a preamp. You can convert between the two. The math to do so is shown here:
http://www.giangrandi.ch/electronics/anttool/decibel.html

You can get away with less signal in a digital distribution system than an analog system.

I would expect that you could get anything on your tvfool list that is stronger than about -93 dbm. VHF/UHF shouldn't matter. An aggressive antenna would pick up a few more analog LPTV stations. I wouldn't bother.

Your friend is using dbuv numbers. tvfool uses dbm. uv referes to microvolts in a 75 ohm system; dbm refers to milliwatts. The -10 dbuv preferred measurement is usually after a preamp. You can convert between the two. The math to do so is shown here:
-----------------]

You can get away with less signal in a digital distribution system than an analog system.

Thanks Tower Guy!!:)

You can get away with less signal in a digital distribution system than an analog system.[/QUOTE]


That's for sure, however, it'd just be nice to be able to tap the local market and the reach a little to places like Wilmington, Greenville, Burlington, Asheboro, and maybe even Norfolk, Va just to see what else is going on around in this crazy world.

I've seen others talk about Winegard products, but the performance specs are a tad better with Channel Master, down in Smithfield. I may buy some Winegard stuff later especially since they are made in Iowa.

I grew up with Channel Master antenna back in the '60's in Fayetteville.
We only could get 3, sometimes 4. WRAL, WTVD and WBTW-13 out of Florence, SC. Sometimes, we'd get WECT out of Wilmington.

The conversion link is definitely a keeper.

The CM 7777 specifies a VHF gain of 23dB or 131.75 dBµV and a 26 dB or 134.75 dBµV gain for the UHF. I chose that pre-amp because I might later do something weird like add a UHF antenna on top and then split the inputs from each antenna using the CM 3671 for VHF only and leave the antennas stationary. I'd most likely have to move the CM 4221 (a wind sail) to a different mast setup (if I went to that setup) to angle it some and up.

It all depends on what I wind up 'seeing'. Stuff like this can get interesting, and I'm sure it will be once I get things going. The 1080i is in the plan, but, not for a year or so. I do not watch that much tube on a daily basis unless I'm sick or it poor weather and all the inside chores are caught up

Figured I take what I save on the D*TV and pay for the systems.

I just installed a CM4221 on a 10' mast on the roof. Antenna pointed approx. 130*. Digital reception is fantastic, just purchased a Vizio HDTV. The main channels I watch now are 8.1, 25.1, 35.1, and 46.1, plus some analog. I have rotated the ant. to receive 36.1 and some other analogs which comes in very clear. Can I install a 2nd CM4221 pointed in this direction on the same mast? I really don't want to use a rotor. I have tried taking the screen off of the ant, but it doesn't pick up 36.1 without the screen. If I can use 2 antennaes, can they be back to back, or one above the other? Thanks, Tom

I would expect that you could get anything on your tvfool list that is stronger than about -93 dbm. VHF/UHF shouldn't matter. An aggressive antenna would pick up a few more analog LPTV stations. I wouldn't bother.

Your friend is using dbuv numbers. tvfool uses dbm. uv referes to microvolts in a 75 ohm system; dbm refers to milliwatts. The -10 dbuv preferred measurement is usually after a preamp. You can convert between the two. The math to do so is shown here:
http://www.giangrandi.ch/electronics/anttool/decibel.html

You can get away with less signal in a digital distribution system than an analog system.
Careful....tvfool Rx(dBm) level is using F(99,99) statistics--expressing the signal level
during the deepest fade in the worst location for the worst time of the day/year.
In other words, it is trying to calculate "worst case" propagation conditions.

andy.s.lee's Rx(dBm) recommendations are empirically derived, but do not
include several important variables such as whether through trees (variable loss),
whether indoor/attic (13 +/- 7 dB loss), antenna gain (0-15+ dB) and whether
preamp or not (typ. 10 dB improvement). So YMMV....a lot....

andy.s.lee posted a comparison of F(99,99) "worst case" signal levels vs
F(50,50) [i.e. mean signal level for a location in the mean of the distribution]:
http://www.avsforum.com/avs-vb/attachment.php?attachmentid=94800&d=1195561571
http://www.avsforum.com/avs-vb/showthread.php?p=12266426&#post12266426
Note that there is 20-30+ dB difference for smooth earth model.
Irregular terrain difference could be even more...

F(50,50) is closer to what an average reading spectrum analyzer or signal level
meter will read and is important when calculating overload levels.

If you read back from the above post, you will see further discussion as well as
my earlier determination that tvfool's Rx (dBm) was about 19.5 dB LOWER than
F(50,90) "average" signal level for line-of-sight conditions and more for diffraction.

Lukes,
You've got an interesting signal field; rabbit-ears for all the networks in one direction, and then a range of challenging signals all around; perfect for a tall mast, rotor and big antenna!
Frank

I just installed a CM4221 on a 10' mast on the roof. Antenna pointed approx. 130*. Digital reception is fantastic, just purchased a Vizio HDTV. The main channels I watch now are 8.1, 25.1, 35.1, and 46.1, plus some analog. I have rotated the ant. to receive 36.1 and some other analogs which comes in very clear. Can I install a 2nd CM4221 pointed in this direction on the same mast? I really don't want to use a rotor. I have tried taking the screen off of the ant, but it doesn't pick up 36.1 without the screen. If I can use 2 antennaes, can they be back to back, or one above the other? Thanks, Tom

The 4221 has a wide pattern, so you're getting quite a few stations with one postion.
http://www.hdtvprimer.com/ANTENNAS/cm4221.html

The back lobes are small in the directions the two antenna would face, so you might jockey them a bit to get nulls lining up without sacrificing too much foward gain. At 90* to each other, they don't see each other. You need 145* and 178*...

Combining two antennas pointed in different directions (not "ganged") has signal implications. Each antenna loses 1/2 it's power when combined, so you might need a bigger one for the weaker station, and mount it higher. A lower-loss alternative is to run parallel lines into the house and use a switch.
http://www.hdtvprimer.com/ANTENNAS/merging.html

I wonder, what do you get from the stronger stations with it aimed at 36? The reason I ask is that the rear lobes of the 4221 are at 135* and 180*. If it works, you stay with one antenna.

Frank

Lukes,
You've got an interesting signal field; rabbit-ears for all the networks in one direction, and then a range of challenging signals all around; perfect for a tall mast, rotor and big antenna!
Frank

Currently, in the MBedroom on rabbit ears on an old 19 inch (RF in only) with the rabbit ears facing south on the southern half of the house-being in a hole too) I get 8 UHF and 3 VHF channels. That's surprising in that the Rat Shack power antenna usually has to have the gain turned down too at night.

Last night, CBS and NBC were clear as a bell with that old set on the analog stations.

Eventually a 1080i in the great room and the 27" tube Phillips to the bedroom.
I'm happy with that set as it has a really good picture for a 580V resolution on a 4:3.

The Samy DTB260F cannot even 'connect' to the 19" as HD digital is only provided on the component and HDMI connections. I have to pull the y off the component out on the receiver to the composite in on the 27" just to get the OSD to come up...what a pleasure.:rolleyes:

Anyway, working on the now and future tech. Laying out the dough for wholesale HD conversion at this time is a little steep. Will have to do it on the incremental as I figure I don't want just the cheapest I can pick up. I've been virtual shopping for sure.

To be honest, some HD LCD's aren't that good in person...too washed with regards to brightness and sharpness. The Phillips 27" tube has a better picture especially when viewing 8-12 ft away. I like the Phillips LCD's too for their pictures as well as some of the Sharp's, Toshiba's and Samsung's, but not all models.

When I put my own SAT in (DrecTV) in '97 there was only one model up (HDTV) on the receiver...that Hughes was almost $800 then) and HDTV sets were $10K-$20K. I still went with the triple LNB dish as to get the locals on SAT being 'in the hole'. Had TWC before that and every thunderstorm it went out and the Discovery channel faded over time constantly. Being the last house on the feed in the rural subdivision with the type filter traps they used created that....every 3 months, service call.

Anyway, DirecTV service ends here on the 15th. I haven't added any programming in 3 years and they have increased their bill almost 30% over that time frame.

It won't be long before HDTV will be broadcast on cell phones and laptops over the WI-FI for those that want to pay for it. Believe me, Verizon has been doing one heck of a build out in the last 5 years up in the NE especially. I know, they buy our fiber opitc cables...I qualify those designs.

For those with cable, complete al-le'-carte programming isn't far off as video on demand is hitting big in a Chicago test market. I mean the local networks, pay-review, movies, sports, and other 'daily' channels like History, TBS, TNT, FoodNetwork, DIY, ESPN, Disney, AMC, TCM, FMC etc. Of the 150 channels on the SAT, I only watched 10-15 channels regularly. I'm gonna miss AMC, TCM, and FCM. XM SAT was good too fo' the blues on Friday nights as well as the jazz, '60's, '70's, classic rock stations, etc. I only watch TV an hour or so (that's split morning and nights) a day during the week and may 2-3 hr / day on the weekends at most.

I'll have to find a forum somewhere where they talk about Jim Cantore' from the Weather Channel 'foaming at the mouth' while broadcasting from hurricane strikes and blizzards......that guy can really hype up a storm......Katrina got his goat good....he'd never seen anything like that. :eek::D:cool:

The 4221 has a wide pattern, so you're getting quite a few stations with one postion.
http://www.hdtvprimer.com/ANTENNAS/cm4221.html

The back lobes are small in the directions the two antenna would face, so you might jockey them a bit to get nulls lining up without sacrificing too much foward gain. At 90* to each other, they don't see each other. You need 145* and 178*...

Combining two antennas pointed in different directions (not "ganged") has signal implications. Each antenna loses 1/2 it's power when combined, so you might need a bigger one for the weaker station, and mount it higher. A lower-loss alternative is to run parallel lines into the house and use a switch.
http://www.hdtvprimer.com/ANTENNAS/merging.html

I wonder, what do you get from the stronger stations with it aimed at 36? The reason I ask is that the rear lobes of the 4221 are at 135* and 180*. If it works, you stay with one antenna.

Frank

Thanks for the post....I did not realize that both antennas lose roughly 1/2 power when the signals are combined.

Careful....tvfool Rx(dBm) level is using F(99,99) statistics--expressing the signal level
during the deepest fade in the worst location for the worst time of the day/year.
In other words, it is trying to calculate "worst case" propagation conditions.

andy.s.lee's Rx(dBm) recommendations are empirically derived, but do not
include several important variables such as whether through trees (variable loss),
whether indoor/attic (13 +/- 7 dB loss), antenna gain (0-15+ dB) and whether
preamp or not (typ. 10 dB improvement). So YMMV....a lot....

andy.s.lee posted a comparison of F(99,99) "worst case" signal levels vs
F(50,50) [i.e. mean signal level for a location in the mean of the distribution]:
http://www.avsforum.com/avs-vb/attachment.php?attachmentid=94800&d=1195561571
http://www.avsforum.com/avs-vb/showthread.php?p=12266426&#post12266426
Note that there is 20-30+ dB difference for smooth earth model.
Irregular terrain difference could be even more...

F(50,50) is closer to what an average reading spectrum analyzer or signal level
meter will read and is important when calculating overload levels.

If you read back from the above post, you will see further discussion as well as
my earlier determination that tvfool's Rx (dBm) was about 19.5 dB LOWER than
F(50,90) "average" signal level for line-of-sight conditions and more for diffraction.

Thank you for that post....The loss graph w/ respect to terrain is good info.
The terrain around here in the Raleigh area is 'slightly hilly' with my 180-190º LOS is looking up hill some ( 50-60 ft) for a half mile or so and 40-60 ft hardwoods all over that. After that....the top of the 'hill' in that direction is higher (maybe 50-60 ft best guess) than the transmitters in Auburn (along I-40) SE of Raleigh. The towers there are 1900-2000 ft.

My thinking is that getting 8 UHF analog and 3 VHF locals of the rabbit ears is that the chimney mount with the CM 3671 and rotator will be pretty good. I'm getting the CM 7777 as insurance. I wish I could get my hands on a signal meter for the analogs right now.....that would make sighting and design (mast elevation) much quicker and accurate for my specific location as they will not be moving those towers...just the frequencies and power.

The roughly -20dB loss for the F(50,50) versus the F(99,99) is significant from the model. I may be lucky in the sense that the 'Cliff Effect' is not too significant in my specific location w/ regards to signal path. It was interesting last night as the OTA analogs were pretty good with a low cloud deck and drizzle. My guess would be that the lower deck may have helped in redirection of the signal path some as to move the edge of the cliff a little.

So, could I take that graph and rescale it my self for a 2000 ft tower and a 30 ft antenna? That should push the loss values up and that relationship would also be logarithmic w/ regards to the F(50,50) and F(99,99) models?

I realize that if I did that, I'd most likely have a 30% lower value if I measure the signal from Chl 5 here locally because of 'the local hole' and the trees.

The 1st edge and 2nd edge diffractions signal behaviors is something else I need to read up on to get a good hand.

I just hope I get a decent 'sweet spot' off my chimney.

Once again I seriously appreciate your reply. I did not know TVFool was using the worst case in their signal predictions. That's a positive in my case.

The more your engineer types post with regards to the tech stuff....the more I'm thinking the CM 7777 is going to make the signals too hot for the locals facing south, but, after the swaps occur on 02/19/2009 I'll have it in case someone drops power on their new xmtr.

I'm gonna hunt me an in-line variable attenuator to put in from after the FM splitter out and before the splitter that will tap to the bedroom.

[QUOTE=Lukes;13555207]
...
The more your engineer types post with regards to the tech stuff....the more I'm thinking the CM 7777 is going to make the signals too hot for the locals facing south
...QUOTE]

That's one reason I mentioned rabbit ears; you don't want to aim a really big, amplified antenna at really strong stations.

DTV being threshold-sensitive, all you need is a minimum signal for a perfect picture. An NTIA coupon box and indoor antenna will give all your TVs the southern stations, as they do through the H260. You may not want all TV on the big antenna, either, unless everyone watches the same transmitters. Here are some thoughts:
- consider limiting the rotor travel so you can't aim fully South. You may be close enough to receive them using back-gain or a side lobe, and signal reduction isn't needed if you can't aim South.
- run the antenna to one tuner so any overload issues are in one place. The H260 may have overload protection; I'm not familair with its features. I'm not hearing that any of the CECBs do.

Frank
=======
Here's an even neater idea; put the antenna due North of a big evergreen tree (or plant one due South of the antenna). The tree will be a natural attenuator, preventing overload. Just make sure it's an evergreen; shedding leaves would be bad for your tuner.

Thanks for the post....I did not realize that both antennas lose roughly 1/2 power when the signals are combined.

Lukes, this was a response to workingmantom, not you.

You have a combo UHF/VHF antenna, and the 7777 has separate UHF and VHF inputs, so the 1/2 power things doesn't apply. Read the link I included. The 1/2 power thing is for identical antennas pointed in different directions - what workingmantom wanted to do. You have separate UHF and VHF antennas going into a pre-amp that combines UHF and VHF without any losses. Very different.

Frank

fbov,

I'm look at either the Winegard SS1000 or the SS2000 to replace the Radio Shack antenna that I'm going to return. However, I noticed that it is designed to receive only channels 14-69. I suppose that is a moot point in terms of analog stations that are soon to be history, but I also heard that some digital channels will be using the higher end of VHF also. How does one determine if this applies within their local area?

It's called the Square Shooter in the link.
http://www.hdtvprimer.com/ANTENNAS/comparing.html
http://www.hdtvprimer.com/ANTENNAS/SquareShooter.html

Reasonable 8-10 dB gain, neat dipole element shape (click the Flash demo on Winegard's Square Shooter page). Not much good in the VHF (link explains why). For a strong signal field, it's a good choice, and for $8 more, I'd get the amp, especially if you have a long coax run.

It's in the same family, but likely more robust than the RS antenna. (I'll admit I've had to do a lot of reading to remind myself who you are and what you need.)

Frank

I rechecked TV Fool and it shows 3 stations in the High VHF range...NBC, ABC and PBS. I would not like to lose these because of a limited antenna...is there another choice similar to Square Shooter? I like it's stealth design, and it's ability to block multipath signals.

[QUOTE=Lukes;13555207]
...
The more your engineer types post with regards to the tech stuff....the more I'm thinking the CM 7777 is going to make the signals too hot for the locals facing south
...QUOTE]

That's one reason I mentioned rabbit ears; you don't want to aim a really big, amplified antenna at really strong stations.

DTV being threshold-sensitive, all you need is a minimum signal for a perfect picture. An NTIA coupon box and indoor antenna will give all your TVs the southern stations, as they do through the H260. You may not want all TV on the big antenna, either, unless everyone watches the same transmitters. Here are some thoughts:
- consider limiting the rotor travel so you can't aim fully South. You may be close enough to receive them using back-gain or a side lobe, and signal reduction isn't needed if you can't aim South.
- run the antenna to one tuner so any overload issues are in one place. The H260 may have overload protection; I'm not familair with its features. I'm not hearing that any of the CECBs do.

Frank
=======
Here's an even neater idea; put the antenna due North of a big evergreen tree (or plant one due South of the antenna). The tree will be a natural attenuator, preventing overload. Just make sure it's an evergreen; shedding leaves would be bad for your tuner.

Thanks for the response, Frank.

Didn't mean to offend by butting in on the 1/2 power antenna loss talk with the other poster.

I only get from 8-11 digital stations on the rabbit ears on the DTB receiver. Half of them fade out.

I'll try to get a pic uploaded soon of what I am looking at at 190º (mag).
I got a heaping boatload of God's natural attenuators (broad leafs) looking in the direction, plus, at 30ft from the ground (top of the 3671), it will still have to look over hill another 20ft or so, and that's the ground with there trees on it.

I'll post a second pic on the street (not mine-2 houses over) standing roughly the same elevation as the base of the chimney so you can see the rise to the hill...the street runs the exact same direction.

Once again thank you w/ regards to running the antenna to only one receiver for the possible overload scenario. I plan on having a variable attenuator downstream of the FM splitter before the coax goes to the HD receiver to adjust the gain when needed. At this time, I believe I read that only hot VHF would cause overload problems with the TDB 260, but I can't find it now.
The link below is a review on it. I want to say it is not an issue with the UHF for that particular newer receiver.

I plan on using outdoor type f hex-crimp connectors with o-rings and spark plug gel inside of each for any connectorization, inside and out. I don't see the need for laying the extra out for the newer compression tool and the Digicon connectors, which I like a lot.

I'd like to find a local supplier for the weather boots for all connections on the RG6 outside.

The CM 7777 comes with 3, but, I'll need another on the downstream side of the grounding block., plus, I'll have another grounding block connection from the now Sat install before the ccoax goes into the crawl space.

Any suggestions as where to look local chain stores, or is it quicker to go on-line? Back in the '70's and '80's, I could buy just about any common / standard electrical part; diode, resistor, cap, transistor, small inductive coils, etc. at Rat Shack.

Those HD tranmsitters look pretty 'hot'.

http://www.w4cl.net/fox/CH35DIGITALTX.jpg

According to the link: http://hdtvexpert.com/pages_b/h260f.html


from the article....the receiver needs a 20-25 dBM to lock on.

2 nights ago most of the 11 channels (5-7) would drop out regularly on the rabbit ears, so I don't think there will be a problem with the signal being too hot in that WRAL was hardest station in the 190º range to pick up.

My most stable channels were actually with the antenna actually close to the north wall of the house next to a window at that time with the aerials turned 90º to the NE/SW as well as the UHF loop. If it weren't raining tomorrow, I'd drag a power strip, the tv, the receiver on the back deck and play some with that antenna vs reception. Steel clad French doors to the deck with those facing almost due south.

I knew the rotator was a must with that 3671 for weak and hot channels.

I'll have to play some more tonight (inside) to get a better idea of reception on the ears. I reconnected back to the Sat in the meantime.:rolleyes:

n4yqt,

I appreciate the suggestion, but I must emphasize that I need a STEALTH antenna, which is also good at blocking multipath signals.

n4yqt,

I appreciate the suggestion, but I must emphasize that I need a STEALTH antenna, which is also good at blocking multipath signals.

Is this what you're looking for? I have not tried it myself.

http://www.solidsignal.com/prod_display.asp?PROD=AD-LACROSSE-A

Tower Guy,

That would be fine, except that it excludes the hi VHF stations, just like the Square shooter.

EDIT: Looking closer, it is also a multi-directional antenna, which everybody tells me to stay away from, and it said nothing about multipath rejection.

Due to the wave lengths involved any antenna that has directivity on VHF needs to be larger than the square Shooter.
John

Okay...then what is the smallest directional antenna that will includes Hi VHF and multipath rejection?

Multipath rejection requires high F/B ratio and narrow beamwidth. This means a larger antenna (read: not very stealthy) or stacking smaller ones. There's no other magic way to do it at the antenna.

Alternatively, experiment with antenna position, height, and aiming. Sometimes even non-intuitive aiming can catch a bounced signal which is better than the direct one.

Also, consider a variable attenuator from Radio Shack. It can attenuate the multipath enough for a better lock on the signal. Everyone needs one of these to play with anyway IMO.

Finally, the 5th gen LG and Samsung OTA tuners seem to be better than others rejecting multipath.

cpcat,

It's beginning to sound as though it would be easier to move to a different apt than to get good reception in this one. I do have a request placed for another unit within my complex, but that may take some time for one to come open. This will certainly play a part in my decision about which one to accept

I typed "antenna attenuator" into the search window of the Radio Shack website, but it found nothing. Is there a different term for it?

My tuner does an "excellent" job of blocking multipath signals...it blocks everything.

cpcat,

It's beginning to sound as though it would be easier to move to a different apt than to get good reception in this one. I do have a request placed for another unit within my complex, but that may take some time for one to come open. This will certainly play a part in my decision about which one to accept

I typed "antenna attenuator" into the search window of the Radio Shack website, but it found nothing. Is there a different term for it?

My tuner does an "excellent" job of blocking multipath signals...it blocks everything.

Get a Zenith converter box and try it with whatever is the biggest antenna you can handle even if it is just rabbit ears. If it works wait for a good 6th gen real tuner.

I have the Zenith box and the latest 5th gen Samsung tuner. The Zenith beats it by an order of magnitude. With a simple indoor antenna I can get the same stations on each, but the Zenith will get them at almost every antenna direction. The Samsung requires careful aim.

It's part #15-578. Seems to be discontinued on their website but possibly could still be found at a local RS store. Call with the part # to see. You can also use fixed in-line models or even plain ole splitters to attenuate but that requires more trial and error.

The tuner can make a significant difference. The Samsung DTB-H260 is excellent and fairly reasonable. LG 5th gen tuners are available on the D* H20 STB as well as LG-made HDTV's.

I have the Zenith box and the latest 5th gen Samsung tuner. The Zenith beats it by an order of magnitude. With a simple indoor antenna I can get the same stations on each, but the Zenith will get them at almost every antenna direction. The Samsung requires careful aim.

Interesting. What Zenith model is this? I wonder if it contains the LG 5th gen (Zenith=LG basically). My experience is the LG is slightly better than the Samsung for long distance reception.

Okay...then what is the smallest directional antenna that will includes Hi VHF and multipath rejection?

Winegard's HD-769x series is a new line designed for VHF-high and UHF, but they're not small except compared with full range VHF. Nothing that does VHF well will be small! Sorry.
Frank

... Didn't mean to offend by butting in on the 1/2 power antenna loss talk with the other poster.

I only get from 8-11 digital stations on the rabbit ears on the DTB receiver. Half of them fade out.

I'll try to get a pic uploaded soon of what I am looking at ...

Lukes,
No problem, butting in is joining in. I just wanted to be clear I was responding to a different question.

I only expected you'd get ~8 stations on rabbit ears, and I understand what local terrain can do. You've done the best you can, however it turns out!

Good luck,
Frank

It's called the Square Shooter in the link.[...] Not much good in the VHF (link explains why).

The link says the Square Shooter is only good for vertical polarization at VHF frequencies. This may or may not be a problem. According to the FCC database, some stations are transmitting with circular polarization, which will work with a vertically polarized antenna as well as a horizontal one. It's worth checking if you really need a small antenna.

Time to tap the knowledge base:

First of all, if you are a member of this fourm, we can agree you have a passion for antennas! Pushing the system, and trying to get deep fringe signals and bragging to your neighbors is my fame. ;)

So, I am about ready to pull the trigger on ordering a tower. In my previous post, I quoted out a 50' American tower. Now, I am considering the possibility of the Rohn BX series. That is the 64' or 72' jobs.
(Be ready to open your wallet)

72' BX Series - $1850
Labor $350
Concrete $250
Total $ $2450

Advantage - house bracket not needed, and has a higher wind load capacity.

The American 50' is $850 installed.

So, do you really gain much for the "extra cost" to have the additional 22' in the air? I mean, really?

In my days of Ham Radio, 22 ft meant the world. But for deep fringe TV, I was under the impression that anything over 80 miles is more dependant on weather conditions than anything.

Thanks for your feedback!

cpcat,

I did find one attenuator:

http://www.solidsignal.com/prod_display.asp?prod=TA-8700

But I'm still very unclear as to what advantage that this would have in my situation. If you reduce the gain with it, won't it reduce all signals, not just the ghost signals?

Winegard's HD-769x series is a new line designed for VHF-high and UHF, but they're not small except compared with full range VHF. Nothing that does VHF well will be small! Sorry.
Frank

I ran that number through btoth Google and Winegard Direct and could find nothing.

EDIT: Nevermind, I used n4yqt's link and found it.

So, do you really gain much for the "extra cost" to have the additional 22' in the air? I mean, really?

Assuming that trees are no an issue at either height, go to tvfool.com, enter the two heights that you are considering, and compare the results. If a station that you want to get is color coded gray and gains more than 3 db, the extra height may be worth it, if not, buy a second antenna and stack it.

In my case some stations got stronger on a taller tower and some got weaker.

Since there doesn't seem to be a viable option for an antenna that performs as I want...stealth, high VHF, UHF, directional and multipath rejection, I'm wondering if I might be able to modify the Radio Shack antenna that I have by covering the rear or the antenna case with aluminum foil or something that would give it a high F/B ratio?

Interesting. What Zenith model is this? I wonder if it contains the LG 5th gen (Zenith=LG basically). My experience is the LG is slightly better than the Samsung for long distance reception.

My Zenith converter is the DTT900 january 08 production. It has the LG 6th generation chip. I've found little difference with my older LG and Samsung tuners on sensitivity, sometimes one works better and sometimes the other.
But I use a preamp on my mast, so this may hide the differences.

But the Zenith is far better than my new Samsung DTB-H260F around multipath and that Samsung beats my older 165 model.

For perspective with an indoor antenna:

Old Samsung 165 could get usably about 4 channels.

New Samsung on same antenna gets about 12 including all locals.

The Zenith gets the same but antenna aim is far less critical: eg I get Boston one direction and Worcester at 90 degrees. I can aim so I get both at one position.

None get the fringe stations on indoor antenna, so this is only really a multi-path comparison.

My Zenith converter is the DTT900 january 08 production. It has the LG 6th generation chip. .

Does that converter have HD outputs?

It sounds like you are getting excellent performance for multipath. Do you know for certain that it contains the 6th Gen LG chip?

cpcat,

I did find one attenuator:

http://www.solidsignal.com/prod_display.asp?prod=TA-8700

But I'm still very unclear as to what advantage that this would have in my situation. If you reduce the gain with it, won't it reduce all signals, not just the ghost signals?

That should be very similar to the RS model.

These have been used historically to attenuate multipath for analog signals. It will attenuate the overall signal but also the ghost signal(s) and can depending on the situation improve the lock with a digital signal as well.

I use one to fine tune the gain after a post-amplifier right before my tuners.

Figures that the analog boxes would have the 6th. I've been waiting as the DTB-H260F isn't quite enough. This one?
http://www.zenith.com/dtv/downloads/DTT900_spec_sheet.pdf

I'm curious, all of the discussion about which generation chipset that a tuner uses makes me wonder if a generation is the same regardless of the manufacturer? My tuner has what it calls a 7th generation chipset, but I'm not sure how they count it.

The R-S "Disc" antenna (Antenna Craft ) is also stealthy, although like ANY
small antenna isn't going to do much for VHF (minus 6.6 dBd Hi-VHF gain):
http://www.radioshack.com/product/index.jsp?productId=2348191&cp=2032057.2032187.2032189.2032205&parentPage=family
http://www.antennacraft.net/HDX1000.htm

If the "Disc" isn't enough for VHF, you could add a VHF-only antenna, such as
a DIY Folded Dipole (0 dBd gain on cut" channel), using UVSJ UHF/VHF Coupler:
http://www.solidsignal.com/prod_display.asp?PROD=UVSJ
http://www.wfu.edu/~matthews/misc/dipole.html
You might get away with an indoor location for the VHF antenna, although
the UHF antenna should be outside for best performance.

FYI: Antennas Direct also has a variable RF attenuator:
http://www.antennasdirect.com/attenuator.html
which looks the same as this OTHER one on SolidSignal:
http://www.solidsignal.com/prod_display.asp?prod=1296F

I just updated the "CECB Features List" spread sheet for the
NTIA Coupon eligible Converter Boxes:
http://www.avsforum.com/avs-vb/showthread.php?p=13567441&#post13567441
If you read through the thread you will find that several of the (few)
available boxes have audio and lock-up problems....be forewarned....

ALL CECB converter boxes must meet NTIA performance requirements, derived from
ATSC A/74 which could not be met by "5th Gen" chips....hence ALL are "6th Gen":
http://www.ntia.doc.gov/dtvcoupon/DTVmanufacturers.pdf

We should be seeing "6th Gen" performance in other products
produced since about mid-2007.

Since there doesn't seem to be a viable option for an antenna that performs as I want...stealth, high VHF, UHF, directional and multipath rejection, I'm wondering if I might be able to modify the Radio Shack antenna that I have by covering the rear or the antenna case with aluminum foil or something that would give it a high F/B ratio?

1/2 inch chicken wire (available at Lowe's or Home Depot) is a useful tweak added to the reflector on a yagi/corner reflector type antenna. This will only improve the uhf section performance however and I frankly don't know how it would effect the vhf performance on a combo type antenna. Cut it to proper size (one half for each half of the reflector) and attach with zip ties.

This will increase wind loading on the mast. I've compromised by only covering about 2/3 of each side of the reflector.

The R-S "Disc" antenna (Antenna Craft ) is also stealthy, although like ANY
small antenna isn't going to do much for VHF (minus 6.6 dBd Hi-VHF gain):
http://www.radioshack.com/product/index.jsp?productId=2348191&cp=2032057.2032187.2032189.2032205&parentPage=family
http://www.antennacraft.net/HDX1000.htm

Though I hadn't mentioned it for a while, that R-S Disc is what I have now. Analog stations come in snowy, and HD/digital stations don't come in at all most of the time.

If the "Disc" isn't enough for VHF, you could add a VHF-only antenna, such as
a DIY Folded Dipole (0 dBd gain on cut" channel), using UVSJ UHF/VHF Coupler:
http://www.solidsignal.com/prod_display.asp?PROD=UVSJ
http://www.wfu.edu/~matthews/misc/dipole.html
You might get away with an indoor location for the VHF antenna, although
the UHF antenna should be outside for best performance.

I'm not sure that I understand, is that coupler simply a splitter or something more? Do you think that it might work to simply use a pair of rabbit ears that I have, along with the Disc? If so, would it matter if the coax between the coupler and the antenna were the same length and type?

FYI: Antennas Direct also has a variable RF attenuator:
http://www.antennasdirect.com/attenuator.html
which looks the same as this OTHER one on SolidSignal:
http://www.solidsignal.com/prod_display.asp?prod=1296F
Would I need the attenuator with the 2 antennas described above?

1/2 inch chicken wire (available at Lowe's or Home Depot) is a useful tweak added to the reflector on a yagi/corner reflector type antenna. This will only improve the uhf section performance however and I frankly don't know how it would effect the vhf performance on a combo type antenna. Cut it to proper size (one half for each half of the reflector) and attach with zip ties.

This will increase wind loading on the mast. I've compromised by only covering about 2/3 of each side of the reflector.
The only problem with using chicken wire is that there isn't a good way to attach it to a Radio Shack Disc. I was thinking about something that I could simply tape to the antenna long enough to see if it would work.

I'm not sure that I understand, is that coupler simply a splitter or something more? Do you think that it might work to simply use a pair of rabbit ears that I have, along with the Disc? If so, would it matter if the coax between the coupler and the antenna were the same length and type?

?

The UVSJ might be the better option to provide increased vhf performance. You could even couple an indoor pair of rabbit ears to your incoming downlead just to try. The lengths of coax won't matter as the UVSJ will filter all the vhf off of the downlead and any spurious uhf from the rabbit ears. Attach the downlead from the RS antenna to the uhf input on the UVSJ, the rabbit ears to the vhf input on the UVSJ, and the common output to the tuner/tv. If your RS antenna is amplified, be sure to do the coupling after the power supply to the RS antenna.

Does that converter have HD outputs?

It sounds like you are getting excellent performance for multipath. Do you know for certain that it contains the 6th Gen LG chip?

Converters are for NTSC tv and coupon forces it not to have HD.

That is why I updated my Samsung 165 to the 260 even though it is 1 gen older. I will update more tuners with HD tuners soon as someone makes one that can match the 6th gen LG chip.

My multipath is very bad and I have to re-aim my antenna even for rain with all tuners older tuners.

And yes the LG 6th gen chip is in the Zenith.

I will hopefully try some other chips in converters when I get coupons so I know what else might work for me.

But everything depends on location. You may not have multipath that bad and just need a better antenna and preamp, or have blocking so need a tuner with more selectivity. There are lots of differences and no useful specs on anything that I can find.

Be nice if other 6th gen chips work well too but I wouldn't count on it. And be nice if there was a floor spec for more than just converter boxes.

cpcat,

Thanks, I just ordered the coupler, but since I use PayPal eChecks, it will probably be about a week before I receive it. Whether it works or not, it's worth a shot. But I'm still hoping that you might respond to my question regarding the chickenwire/foil aspect.

> I did find one attenuator

> If you reduce the gain with it, won't it reduce all signals,
> not just the ghost signals?

An attenuator is useful if your signal is too strong and the tuner
is overloaded. The distortion is reduced a lot more than the signal.
If your signal is too strong, reducing it isn't bad.

An attenuator is useful if your signal is too strong and the tuner
is overloaded. The distortion is reduced a lot more than the signal.
If your signal is too strong, reducing it isn't bad.
Understood, but in my case I doubt it would be of any help, because none of the HD signals exceed 85%, which I have been told is too low. I need to increase these signals, while decreasing the multipath signals.

Actually an attenuator can be used for more than just preventing overload at the tuner. With multipath the problem isn't overload, but signals arriving from more than one direction and slightly ahead of or behind the direct signal. The attenuator can produce a less ghosty image on analog and more consistent locks with digital by attenuating the indirect signals down closer to the threshold of sensitivity on the tuner (therefore the tuner can more easily "ignore" them).

CPcat,

The thing that I still fail to understand is when attenuating a ghost signal down closer to the tuner's sensitivity threshold, isn't it also doing the same thing to the desired signal? I'm assuming that when the threshold is met, that it that the desired signal is remaining, but at a lower signal strength than before. Since none of my HD signals are greater than 85% (and many much less), will the remainder be sufficient?

Love to see a lively thread! This is mostly to seekermeister.

cpcat's attentuator idea is interesting: minimize the signal until there's only one above the noise to lock on! It should work but a multi-path tolerant tuner is a lot easier!

holl_ands' UVSJ coupler is for joining two antennas from different bands, so he provides a link to a home-brew dipole site. Dipoles work for any frequency, depending on their size. VHF high is 174-216MHz. 1/2 wave is ~27-33", so make a 30" dipole. I'd attach a balun at the feed point (where it goes vertical) and try a 2'x3' mesh reflector 12-15" behind the dipole to increase directional gain.

cpcat's chicken wire is called hardware cloth in my stores, and it's much finer mesh than you need for Ch 14-52. In the pictured application, it could enhance high frequency gain on an antenna optimized for 800 MHz (Ch 70). That said, it is stiffer than most wire meshs and is well suited to applications with minimal physical support.

"HD-769x series" is shorthand for a range of models starting HD-769 with the suffix usually indicating reception range. Sorry for the confusion!

Seekermeister, I don't see anything you can do to modify an existing commercial compact antenna to improve VHF gain. The best idea I see (and I make antennas) is to make the 30" dipole, run it into a balun and combine it with the UHF antenna, either in the aforementioned coupler, or if signals are still too weak, a dual UHF/VHF input pre-amp, and see what you get for VHF reception. If it's close to acceptable, add a reflector and see that helps.

Talking with a buddy last night about radio astronomy, and a 30" dipole with reflector is exactly what I envisioned for his meteor detection project. I'll post a pic when I'm done.

Frank

>> An attenuator is useful if your signal is too strong and the tuner
>> is overloaded. The distortion is reduced a lot more than the signal.
>> If your signal is too strong, reducing it isn't bad.
>
> Understood, but in my case I doubt it would be of any help, because none
> of the HD signals exceed 85%, which I have been told is too low. I need
> to increase these signals, while decreasing the multipath signals.

An amp will make the signal stronger, but will do nothing to help multipath.

A more directional antenna will decrease multipath, and will also give a
stronger signal.

You can try changing the aim of the antenna in hopes of aiming a null at
the reflection giving you multipath. If you know where the reflection
is coming from (a mountain perhaps) you can try to find an antenna with
a null at the correct angle.

You can use two antennas to create a null in the desired direction:
http://www.hdtvprimer.com/ANTENNAS/ganging.html#TAT

cpcat's attentuator idea is interesting: minimize the signal until there's only one above the noise to lock on! It should work but a multi-path tolerant tuner is a lot easier!

I don't think that the attenuator idea will work to tame digital multipath. If there is multipath the dynamic equalizer needs a higher signal to noise ratio to decode the signal.

In an analog system the attenuator could bury a ghost in the noise. It wouldn't really eliminate the ghost, but you wouldn't see it either.

fbov,

It seems that even though I have my options set to send an instant email notification by default, if I forget to use the advanced reply to set this on each post, I get no notification. Thus I'm tardy in my response, but I wanted to let you know that I read your last post to my with interest. It seems that I'm going to be doing alot more experimenting that I imagined at the start. HD is nice, but it seems to be a challenge to get it without paying for it.

Lukes,
No problem, butting in is joining in. I just wanted to be clear I was responding to a different question.

I only expected you'd get ~8 stations on rabbit ears, and I understand what local terrain can do. You've done the best you can, however it turns out!

Good luck,
Frank

Thanks.

Stuff is suppose to be arriving this week. I still need to get some hex crimpers, weather boots, strippers, connectors, sil-gel, and especially a good in-line lightning arrestor to work with some later rerouting. Right now, the existing RG6 for the SAT will do what I need for initial setup.

I realize even though I'll be well grounded outside, adding the extra arrestor and the current surge protector that has built in MOV's for surge protection on the coax 'in' & 'outs' too will be the best I can do for lightning protection.

'The trees and my general location ('The Hole') will make LD HDTV reception a challenge to some degree, if possible at all. I am rather confident that the 8 locals will be no problem at this time with that monster 3671. I ordered the CM 7777 as insurance.

None of the local analog signals come in clear 24/7. Early morning and late in the evening the signals improve to my location.

I'm figuring on pointing the 3671 at 225º on the initial start up for the first scan and by passing the pre-amp initially. Then, I'll zero the rotator on magnetic north and start a swing from 75º to 290º for a look at overall reception.

Hopefully, I'll have good weather this coming weekend.:)

I am surprised you did not cover the entire reflector with chicken wire.

1/2 inch chicken wire (available at Lowe's or Home Depot) is a useful tweak added to the reflector on a yagi/corner reflector type antenna. This will only improve the uhf section performance however and I frankly don't know how it would effect the vhf performance on a combo type antenna. Cut it to proper size (one half for each half of the reflector) and attach with zip ties.

This will increase wind loading on the mast. I've compromised by only covering about 2/3 of each side of the reflector.

I am trying to find a good replacement for a Radio Shack VU-190. I am looking at using separate UHF VHF units. As far as UHF goes, I've tried a Channel Master 4228, a Winegard 9095 and one of the new Winegard 7697 combos. The Channel Master was the best of the 3, but none were as good as the Radio Shack. I am at zip code 02891, at sea level, with the antenna outside, on the roof, about 25 feet off the ground. I have been using a Channel Master 7777 on all, but found the Spartan 3 to work better on VHF 13. Any help or suggestions would be appreciated, as I am beginning to have myself quite an antenna collection. Thanks, Walter

http://www.hammacher.com/publish/74605.asp?promo=tested_best_hero

Well, I'm going to try it out anyway. I currently use a Silver Sensor in area code 77429. Overall I'm pretty satisfied with it but sometimes it has a bad day where I have to adjust it multiple times throughout the day. I think it happens more when it's cloudy or raining. Also, channel 8 (PBS) is horrible. I'll compare this to the Silver Sensor and worse case scenario if it's no better I'll just give it to my grandfather as he needs a new antenna anyway; he's in area code 77008. I hope it's at least equal to the Silver Sensor. Anyone in the 77429 area have any antenna's they had great success in using?

I just ordered an antenuator to go along with the coupler, and now I'm thinking about how to connect these along with the inline amplifier that came with the antenna. I'm thinking about making a mounting board that I can hang on a DVD cabinet that abuts the patio door, but when it comes to coax, about all that I know is the lengths and connectors. To do this neatly, I need some short lengths (4" or less), or if such a thing exists, some M-M adapters that would connect these items together directly. The shortest that I have found are 8" flat coaxes for passing through doors and windows, but even these are too long and have F-F connectors. What is available?

http://www.hammacher.com/publish/74605.asp?promo=tested_best_hero
...

Anyone notice this in the description (emphasis added):
"Tested in urban, suburban, and rural environments, the antenna receives UHF, VHF, and local high-definition broadcasts (requires an HD-ready TV to receive HD signals)."

As a recall, an "HD-ready TV" is one without an ATSC tuner ... makes you wonder how the comparison antenna did!

Frank

Be advised that MOV devices will degrade over time, so figure on periodic replacement.

Here is more info re alternative "Gas Tube" protective devices:
http://www.avsforum.com/avs-vb/showthread.php?p=8591196&#post8591196

Ideally you could use all three: Spark Gap and Gas Tube at entry point, MOV as a last resort
protection closer to equipment location so you can readily bypass to test whether it's degraded.

Anyone Know where I can view holl-ands old tests on 7 different baluns?

> I need some short lengths (4" or less), or if such a thing exists,
> some M-M adapters

Yes, they make both F-F and M-M 'F' connector adapters. Total length
about 1 inch or less.

Pico Macom F-71 $9.99 (for 20) (a year or 2 ago, probably higher now)
http://www.picomacom.com/specs/pico/D/D7.pdf

$1.99 (up from $1.35 2 years ago, hello stagflation)
http://www.mcminone.com/product.asp?catalog%5Fname=MCMProducts&product%5Fid=33%2D480

Anyone Know where I can view holl-ands old tests on 7 different baluns?
Per your PM, I reposted BALUN LOSS spread sheet in Antenna/Rotator/Preamp thread:
http://www.avsforum.com/avs-vb/showthread.php?t=546066&page=32

Hi everyone need some antenna help. I just installed the Zenith converter box for my 93 year old grandmother with my indoor terk ampflied antenna before 5:00pm she is getting alot of freezing issues after 5:00 when things seem to calm down it gets better.My problem is her house is very old and mounting a antenna on her chimney is not an option.I need to mount a good light weight antenna that will do the job any ideas? Here is her station info off antennaweb.

* yellow
uhf WKON-DT 52.1 PBS LEXINGTON, KY 53° 18.4 44
* green
uhf WLEX-DT 18.1 NBC LEXINGTON, KY 125° 42.4 39
* lt green
vhf WKYT-DT 27.1 CBS LEXINGTON, KY 125° 41.8 13
* lt green
uhf WTVQ-DT 36.1 ABC LEXINGTON, KY 125° 42.4 40
* red
vhf WHAS-DT 11.1 ABC LOUISVILLE, KY Feb 17, 2009 (post-transition) 276° 42.4 11
* blue
uhf WHAS-DT 11.1 ABC LOUISVILLE, KY 276° 42.4 55
* violet
vhf WKRC-DT 12.1 CBS CINCINNATI, OH Feb 17, 2009 (post-transition) 34° 61.1 12
* violet
uhf WAVE-DT 2.1 NBC LOUISVILLE, KY 277° 41.4 47
* violet
uhf WLKY-DT 32.1 CBS LOUISVILLE, KY 277° 41.4 26
* violet
uhf WBKI-DT 34.1 CW CAMPBELLSVILLE, KY 205° 60.2 19
* violet
uhf WDRB-DT 41.1 FOX LOUISVILLE, KY 275° 42.4 49
* violet
vhf WDKY-DT 56.1 FOX DANVILLE, KY 133° 51.8 4
* violet
uhf WMYO-DT 58.1 MNT SALEM, IN 275° 42.4 51

Konrad2,

Thanks, those splice adapters look like just what I need.

To anyone that has the patience to answer another very basic question, there are a bunch of different types of coaxes...RG this or RG that, with different ohms values. How much difference would one coax be from another in terms of the picture it provides?

> Thanks, those splice adapters look like just what I need.

You're welcome. Most filters have female F connectors on both ends,
as do splitters, so I have a bunch of these in use.

> To anyone that has the patience to answer another very basic
> question, there are a bunch of different types of coaxes...RG this
> or RG that, with different ohms values. How much difference would
> one coax be from another in terms of the picture it provides?

Video coax is 75 Ohms.

RG59 - cheap, avoid if possible

RG6 - this is what you probably want

Lowes carries RG6 quad shield with gold plated connectors and claims
to be weatherproof.

Some recommend Belden 7915A RG-6 tri-shield with solid copper core and
sweep tested to 3GHz.

RG11 - If you are fighting for every fraction of a dB, consider RG11.
The center conductor is too large for standard female F connectors,
so you need connectors with a center pin that steps it down to the
correct diameter.

Don't use Ethernet coax, it's 50 Ohm.

I am trying to improve my reception. More gain with different antennas hasn't helped. Now I wonder if a clue to my problems are in the snr, agc numbers.
Typical readings are signal strength 80, snr 20, agc 110%. What could be causing these poor numbers? Thanks Walter p.S. If I am posting this in the wrong place, could someone let me know.

I have been playing around with 2 parabolic (CM 4251's), and holy cow these things are monsters! They don't look so big on top of a 50' tower, but gosh they are a pain to move on the ground. Jeez...

I could put one in each hand and be lifted off the ground in a wind storm. But hey, if you like UHF, you just can't beat these. If I only could ship these UPS, I could help you guys out.

The Parabolic Man - Chad

By the way, as far as the outdoor baluns with separate, solid leads are concerned, the loss will vary by two or three dB at different frequencies just depending on how you shape the leads. I often use the little mini "Tootsie-roll" sized indoor baluns outside, as mine have less loss and more consistent performance than do the ones designed for outdoor use, but I make sure to weatherize them.

I have a couple of questions. I live in the suburbs and am surrounded by transmitters. The good news is that I am close - none is farther away than 10 miles; the bad news is they are in different directions.

1. With the exception of one channel - channel 10 - all of my HDTV stations are either at 12-13 degrees or 186 degrees. In other words I need an antenna that will pick up from the front and from the back although it can be quite directional. I don't won't to put up one of those 8-bay monsters. Would something like the Antenna Direct DB2 or DB4 work. Would a directional antenna like the Antenna Direct SR15 be an option? Could I get two SR15s, point them in different directionss and combine them. If so, how far apart vertically would I need to mount them.

2. Channel 10 is at 330 degrees and has the weakest transmitter. I was thinking about getting a single channel 5-element yagi like the Dehli (Jerrold) 5Y10S ane join it to the UHF antenna(s) with a VHF/UHF combiner. The question is: I have a unused 6-element RadioShack FM only antenna. Could I just cut down the elements and use it for channel 10. If so, what length should the elements be?

Thanks.

I am trying to improve my reception. More gain with different antennas hasn't helped. Now I wonder if a clue to my problems are in the snr, agc numbers.
Typical readings are signal strength 80, snr 20, agc 110%. What could be causing this poor numbers? Thanks Walter p.S. If I am posting this in the wrong place, could someone let me know.

Walter,
In most cases, the numbers on DTV signal displays are only useful to the user for comparing stations. There is no cross-product calibration that allows you to compare your results with mine.

However, a wonderful gentleman named Andy S. Lee has developed a web site that can tell you what kind of reception challenges you may have. Use your street address - it's hidden in the display - and post your results here along with what's in your rig.
tvfool.com

I bet you get some bites ...
Frank

I have a couple of questions.
...
1. With the exception of one channel - channel 10 - all of my HDTV stations are either at 12-13 degrees or 186 degrees. In other words I need an antenna that will pick up from the front and from the back although it can be quite directional.
...
2. Channel 10 is at 330 degrees and has the weakest transmitter. ... Could I just cut down the elements and use it for channel 10. If so, what length should the elements be?

Thanks.

One easy option when stations are 180* apart is to use a multi-bay antenna like the DB4 or CM4221 without it's reflector. However, these are UHF-only antennas and it's not clear what frequency channel 10 uses now and post-transition. An ideal situation would be a single placement UHF antenna for most channels plus a specifically aimed VHF antenna for the distant VHF10, combined in an unpowered UHF/VHF combiner. If VHF10 is still weak, add a VHF pre-amp at the mast.

Throw us a TVFool chart (as I suggested to Walter) and you'll get a better opinion on your situation.

Frank

Konrad2,

At first I just read your response in the email notification regarding the splice connectors. Fortunately, I looked again at this thread, because the notification didn't contain the part about the cables. When I bought my cables, I grapped the first thing that I saw without paying much attention. Hopefully, the cables are marked, I will have to check.

I do recall reading a promo at one website that offered 50 ohm cable for video, would that be good? Less resistance sounds like a good thing.

EDIT: OOPS! I had missed your comment about ethernet coax. I guess 50 ohm isn't a good thing.

"channel 10" is channel 4.1 using real channel 10.

faberryman,
I'd still like to see that TVFool chart. Mine's attached, as an example. It shows the Big Three: frequency, direction and strength.

I made some suggestions based on what you described. If all your stations are UHF except 4.1 on VHF10, I think you'd be happy with what I suggested, but I can't tell you anything about the tradeoffs - what stations you'd lose compared with other options - without seeing your entire signal field.

Yes, mine is very sparse; I live in a local low spot. Hopefully yours will be far richer.

Frank

fbov,


Yes, mine is very sparse; I live in a local low spot. Hopefully yours will be far richer.

It's no wonder that you know about antennas, you must live in a pit to have such low signals from so close. At least most of them are all in one direction.

Here is my chart. I am only interested in 2.1, 4.1, 5.1, 8.1 and 17.1.

I am using a pre-amp with an outdoor antenna for my pc's tuner cards. If I send the signal through the coax input/output on my surge surpressor, will it dampen the boosted signal from my antenna?

I am using a pre-amp with an outdoor antenna for my pc's tuner cards. If I send the signal through the coax input/output on my surge surpressor, will it dampen the boosted signal from my antenna?
Send an email to the manufacturer for the insertion loss spec. I would guess around .5 - 1.0 db.

I am using a pre-amp with an outdoor antenna for my pc's tuner cards. If I send the signal through the coax input/output on my surge surpressor, will it dampen the boosted signal from my antenna?
MOV devices gradually degrade over time as they drain off static electricity.
So it's something you need to periodically bypass to see if it's a problem.

I have a particular distaste for coax MOVs built into a power strip...do you
really want static electricity being dumped anywhere near your gear???

Antenna protective devices should be installed at the building entry point.

PS: Gas Tube devices don't degrade, although they have higher break down voltage:
http://www.avsforum.com/avs-vb/showthread.php?p=8591196&#post8591196

I am trying to find a good replacement for a Radio Shack VU-190. I am looking at using separate UHF VHF units. As far as UHF goes, I've tried a Channel Master 4228, a Winegard 9095 and one of the new Winegard 7697 combos. The Channel Master was the best of the 3, but none were as good as the Radio Shack. I am at zip code 02891, at sea level, with the antenna outside, on the roof, about 25 feet off the ground. I have been using a Channel Master 7777 on all, but found the Spartan 3 to work better on VHF 13. Any help or suggestions would be appreciated, as I am beginning to have myself quite an antenna collection. Thanks, Walter
Based on zipcode location, I would be concerned re desensitization of your
high gain Preamp by nearby WPXQ (analog & digital) North of you and
two other tower locations further WNW, esp. when you point antenna that way.

FOX & CW are about 70 dB LOWER than strongest stations. That means the
Preamp MUST operate with maximized SFDR (Spurious Free Dynamic Range):
http://www.avsforum.com/avs-vb/showthread.php?p=6290253
http://www.avsforum.com/avs-vb/showthread.php?t=546066&&page=4

I've been slowly working on a revision to the overload calculation
spread sheet....maybe I should take the time to dust it off again....

First of all we need you to either post tvfool results for both digital & analog
stations NOW and Post-Feb2009...or provide location to whatever accuracy
you are comfortable with, such as LAT/LONG to 3 or 4 (or only 2) decimals....
or nearby cross streets so we can "find" you.

ALSO, which stations do you get acceptable & unacceptable reception now.
Which are your first priorities to improve???

BTW: You are only about 15 miles E of Falcon_77 in Mystic, CT.

Here is my chart. I am only interested in 2.1, 4.1, 5.1, 8.1 and 17.1.

You weren't kidding about being surrounded by transmitters! Forget everything I said, since your "top 5" networks are mostly VHF, all LOS, in 3 different directions and provide strong signals.

What are you using now? Have you tried any of the indoor UHF/VHF combos? My reception was marginal-but-present with a simple UHF clip-on bowtie. Your signals are 20dB higher so I don't see you needing a roof top antenna. Crutchfield has a good selection, at a price, that serves as a starting point.
http://www.crutchfield.com/S-O7eesxPPJqy/app/product/group/productmenu.aspx?g=15920

You need with both VHF elements (rabbit ears) and some sort of smaller element for UHF. I have no personal experience with it, but I've heard good reports on the Terk HDTVi, a log-periodic dipole array for UHF and rabbit ears for VHF. If you get an amplified model (many are), make sure you can bypass the amp since you're not likely to need it!

Another option is to put an outdoor antenna in a signal deprived area like your attic. The issue here is that gain comes at the price of directionality, and you need a broad directional pattern or a rotor. That's why I'm thinking indoor combo.

The potential issue hanging over all this is multipath - reflected signals - and your tuner's ability to deal with it. Multipath signals degrade the tuner's ability to lock onto the carrier, and carrier drop outs mean an unwatchable picture. There are things you can do with antennas to limit multipath, but they all rely on directional designs, and that makes it unlikely to find 1 antenna arrangement that works for all stations and directions.

There are also things you can do with tuners, and the new 6th gen tuners are exhibiting superior multipath performance compared with prior versions in some applications. The subsidized ones are cheap after the NTIA $40 coupon, but won't do HD, and their quality varies. You can read more in neighboring threads.

So I should modify my question; what are you using now - both for antennas and for tuners?

Frank

fbov,
It's no wonder that you know about antennas, you must live in a pit to have such low signals from so close. At least most of them are all in one direction.

Please don't confuse me with people who know a lot about antennas. They know I'm not one of them, just a dabbler with a bit of curiosity and a willingness to share my (somewhat rudimentary) understanding in layman's terms.

And I am the poster child for exact locations in TVFool, -25dB down at my house compared with my zip code.

Frank

I don't know how to post my TVfool results without having to type them in. I can give you a street address in the area that should be more than accurate enough. Try 2 South Fairway Avenue, Westerly, RI 02891. Right now, I receive WPXQ and WEDN perfectly. I have ben receiving WPRI, WJAR, and WLNE good most of the time. Today, however, I can"t receive any of those three reliably. WLWC and WNAC can be good a lot of the time, not as good as the other three. WSBE is seldom good, nor, are the Boston stations, but I don't expect to be able to get them. I am looking to improve reliability. Thanks holl-ands
and Frank for your time and help. Walter

Is this what you got? You are about 15 miles east of me but showing lower signal levels. Is your report of reception for analog or digital channels?
John

I recently bought a 13 inch analog/digital tv and put a radioshack vhf back-of-set snap-in dipole and uhf clip-on bowtie (both of which have 300 ohm connectors) and joined them with a double 300 ohm to single 75 ohm combiner that pushes onto the 75 ohm connector on the back of the tv. I've read posts in this forum that discourage the use of push on coax cables. Will this push-on combiner have the same type of signal loss as a push on coax? Is a similar combiner that screws on available somewhere? I'm getting good digital reception right now but am wondering if this combiner might cause a problem eventually.

John-Yes my report is close to that, Mine are all a little bit stronger, some maybe 5 dBm or so. I am speaking about digital only.

For anyone keeping track, most of my stations were all over the place last night, from 0 to 100% signal strength.

Where are you guys purchasing your dual boom stacking kits? (Horizontal) I see them on the A-Tech Website, yet they never answer their phone. Any other places?

http://www.atechfabrication.com/products/dual_antenna_boom.htm

I don't know how to post my TVfool results without having to type them in.

Save the results (a PNG image) to your hard disk. When you post a message, you can upload the image as an attachment, via the "Manage attachments" button at the bottom of the message-composition page.

Here are my exacct TVfool results, both current and post. Thank you jtbell Walter Added more results at post#7038

I recently bought a 13 inch analog/digital tv and put a radioshack vhf back-of-set snap-in dipole and uhf clip-on bowtie (both of which have 300 ohm connectors) and joined them with a double 300 ohm to single 75 ohm combiner that pushes onto the 75 ohm connector on the back of the tv. I've read posts in this forum that discourage the use of push on coax cables. Will this push-on combiner have the same type of signal loss as a push on coax? Is a similar combiner that screws on available somewhere? I'm getting good digital reception right now but am wondering if this combiner might cause a problem eventually.

Did the combiner have separate UHF and VHF connections, like those shown? If so, you're fine. It may not be the highest quality, but there's no reason to pay more if it works. Worst case, replace it when it fails!
http://www.warrenelectronics.com/Antennas/joiners.htm

Frank

Here are my exact TVfool results, both current and post. Thank you jtbell

You've made enough posts that you can add attachments! I wrote a reply to that effect but deleted it lest I monopolize the conversation. Same thing here, but since no one's chimed in recently ...

holl_ands has a valid point regarding overload. The pre-amp is dealing with all stations and frequencies at once, so if it distorts, all channels are affected but the weakest disappear below noise. This can be minimized by use of a high overload pre-amp and a directional antenna with very low gain in the strong station's direction when pointed at weak stations you want. Look at teh spreadsheet holl_ands linked. There's a lot of data, but lots of commentary and color coding. I'm no EE but I got the drift; I bet you can, too.

The only good thing is your pre-transition field has several powerful analog and digital stations, but your post-transition field has only one. If you get it to work now, it'll work even better post transition.

If you have more questions, keep asking!

Frank

Hi All I just got into the antenna and HD realm
Im mostly interested in HD I purchased a treck indor antenna but it doesnt do the trick. I live in a 4 Unit townhouse in wheaton 25 Miles from the Brodcast towers Chicago area. I cant install an outside antenna, but i have a nice attic.

I was thinking about CM 4228
and 7777 preamp

Does this preamp has to be close to the antenna and powered or close to the reciver?

what are your sugestions will this work?

I was reading little bit more and maybe i dont need that big of antenna
what you think about Direct DB2 ?

I get different results on tvfool.com depending on whether I enter my street address, or my coordinates (to 4 decimal places). I've double checked the entries. Has anyone else run into this?

The RX(dBm), Path, and LOS figures are markedly different. The distance figures differ from 0.2 mile to 0.5 mile and direction is a degree different on a few stations..

My guess is that their database doesn't pinpoint my street address very accurately. And, maybe the altitude of my site is known when using coordinates, resulting in better numbers for LOS.

A J

I get different results on tvfool.com depending on whether I enter my street address, or my coordinates (to 4 decimal places). I've double checked the entries. Has anyone else run into this?

The RX(dBm), Path, and LOS figures are markedly different. The distance figures differ from 0.2 mile to 0.5 mile and direction is a degree different on a few stations..

My guess is that their database doesn't pinpoint my street address very accurately. And, maybe the altitude of my site is known when using coordinates, resulting in better numbers for LOS.

A J

The address look-up is much less accurate than LAT/LONG coordinate.

You can readily see this if you search for your address using GoogleEarth, which
uses some sort of (unknown) address look-up database and then plots it onto
SRTM (-1 or -3?) topographic data, which in turn has a photo overlay with
yet another degree of "fitting" inaccuracy:
http://en.wikipedia.org/wiki/Google_Earth

TVFool Radar Plots use SRTM-1 topographic data, accurate (in x & y) to within 10-meters:
http://www.avsforum.com/avs-vb/showthread.php?p=10303057&highlight=srtm#post10303057
So if you have a hill in your backyard (like me) you may need to tweak the
LAT/LONG a little to find the bottom.

Hi All I just got into the antenna and HD realm
Im mostly interested in HD I purchased a treck indor antenna but it doesnt do the trick. I live in a 4 Unit townhouse in wheaton 25 Miles from the Brodcast towers Chicago area. I cant install an outside antenna, but i have a nice attic.

I was thinking about CM 4228
and 7777 preamp

Does this preamp has to be close to the antenna and powered or close to the reciver?

what are your sugestions will this work?
There are no nearby stations to worry about overloading the CM7777, so it
should work up to its potential.

The Preamp mounts as close to the antenna as is feasible. Usually right
next to the antenna connections, but a few feet away is also okay.

The Power Injection Module can be mounted anywhere it is convenient,
such as near a power outlet in the attic or next to your TV:
http://www.solidsignal.com/prod_display.asp?PROD=ANC7777

However, although CM4228 "UHF antenna" has moderate gain for VHF CH7-13,
it won't do much for CH2-6. You probably need a big VHF antenna as well.

Since that might not fit in your attic, you might try a DIY folded dipole:
http://www.avsforum.com/avs-vb/showthread.php?p=13011618&highlight=folded+dipole#post13011618

Although I am interested only in digital stations, I just realized that the existing analog stations could be giving me problems, so I am posting all stations now. Walter

Good News: Not much of a threat wrt overload desensitization.

Bad News: High loss 2Edge paths for ALL digital stations and you need
well over 50 dB dynamic range to receive ABC & CW.

Thanks holl_ands

i have another question

so how many cables do i run to the attick only 1? or 2 cause i know that ill have the power module installed in the room for the 7777 preamp

Thanks holl-ands, but what does that mean in lay-person terms? Walter

I think it means that with any reasonable antenna things are not going to get too much better. My experience with similar strength signals is a large antenna will work 85% of the time and probably nothing short of a tower a few hundred high will work 100% of the time. my experience is that signal levels are stable in the winter except when some weather fronts are comming in and get both much stronger and much weaker on different summer nights. John

So my totally unscientific theory that there is only x amount of signal available to be captured at a given time is true. Once this amount of signal is in hand, bigger antennas with more gain really won't help, this explains why the Uhf section of my old Radio Shack antenna does just as well as the 4228 CM and the Winegard 9095, correct? Walter

Actually the difference in gain between most of the bigger UHF antennas is only 3-4 dB. and the variation with weather is 10 to 20 dB with near fringe edge reception. Your best hope for improvement is to go higher. If you can get above at least one of the edges you will probably see a big improvement.
John

The address look-up is much less accurate than LAT/LONG coordinate.

You can readily see this if you search for your address using GoogleEarth, which
uses some sort of (unknown) address look-up database and then plots it onto
SRTM (-1 or -3?) topographic data, which in turn has a photo overlay with
yet another degree of "fitting" inaccuracy:
http://en.wikipedia.org/wiki/Google_Earth

TVFool Radar Plots use SRTM-1 topographic data, accurate (in x & y) to within 10-meters:
http://www.avsforum.com/avs-vb/showthread.php?p=10303057&highlight=srtm#post10303057
So if you have a hill in your backyard (like me) you may need to tweak the
LAT/LONG a little to find the bottom.
Funny, my experience is the exact opposite. My address comes back perfect but if I enter my Google Earth coordinates, it gives me data for a location about 25 miles east of me.

I live in a single story home with a new 46" Mitsubishi TV after years of watching a 27" Sony. We were hooked up to basic cable tv and the reception wasn't very good so my neighbor made me a 4 bay antenna out of some aluminum foil covered cardboard, aluminum clothsline wire bent into bowties and a wood 2"x 4" for a post. This home made antenna brought in better reception than my cable connection or the Phillips $80.00 antenna I returned to the home store.

Knowing what the home made bowtie antenna did for us and reading the posts in this thread I bought the CM 4228 8- bay and it does a beautiful job at bringing in a great picture for area code 46217.

Free tv is great isn't it?

Thanks holl_ands

i have another question

so how many cables do i run to the attick only 1? or 2 cause i know that ill have the power module installed in the room for the 7777 preamp
I don't know how to make it any clearer than the picture solidsignal provided above.
If you use separate UHF and VHF antennas, the CM4228 connects to
the UHF port on the CM7777 and VHF antenna to VHF port.
The Power Module plugs into 120 VAC wall socket and sends DC power up
the coax to the Preamp.

I know that one should keep a minimum of 3 feet between the booms of a uhf and a vhf antenna, but what about a screen type antenna, CM 4228 and a YA1713? Could they be closer without a negative impact on one or the other, if so how close? Also, when combining the two with a CM 7777, would some or all of the 4228's VHF signal be added to the 1713's or would it be lost?


Thank you John for your help, our locations being so close helps me understand my situation much better. Do you think investing in one of those super low gain English pre-amps is worth a try? Walter

About a week ago I bought a CECB (Digital Stream DTX9900). I reported my initial results from trying to receive digital broadcasts here:
http://www.avsforum.com/avs-vb/showthread.php?p=13562869#post13562869

(See attached TVFool data. Syracuse stations are at 289-301 degrees; Binghamton at 208.)

After I posted that, I made some tweaks, and for a few days I was able receive good signals from six Syracuse stations (WSTM, WTVH, WSYR, WCNY, WNYS, and WSYT). My weakest signal meter reading was typically in the 60s, and my strongest was around 90. I sometimes even got a few Binghamton stations, even though I'm pointed almost 90 degrees away from all of the Binghamton transmitters.

The aforementioned tweaks:
I shortened the antenna cable.
I tossed my bottom-of-the-line Radio Shack pre-amp and installed a Channel Master 7777.
I rotated the antenna slightly (it's a roof-mounted 50-element directional VHF/UHF combo -- unknown model, but it looks like your typical Radio Shack antenna).

By far the biggest improvement was from turning the antenna. The digital transmitters are in the same locations as the analog, and the tripod mount was rock solid, so I think whoever originally installed the antenna just did a sloppy job with his pointing. Either that or for some reason it needs to be pointed differently for digital/UHF than it did for analog/VHF. It's interesting that the one analog station that was always crystal clear was WSYR, and that was my weakest digital signal (usually unwatchable) before I rotated. Go figure.

I was surprised at how much the signal meter jumped around, especially with the weaker signals. But as of last night, I was receiving stable video and audio on all six Syracuse stations, and three Binghamton stations.

This morning, the situation was completely different. Five of the six Syracuse stations had significantly weaker signals, two to the point that I got a black screen. The other Syracuse station was about the same, and oddly enough, so were the Binghamton stations.

I went back up on the roof and confirmed that the antenna was still pointed where it had been, and the mount and all the connections were tight. Everything was fine, exactly the way I left it.

We did have rain and lightning here overnight. Now I know, the obvious conclusion is something got zapped, but I don't think so, for the following reasons:

1) The amount of signal loss varies widely. Signal meter readings have dropped anywhere from only about 10 points to about 60 points.
2) I've had an antenna in the same spot for 15 years and never been hit before.
3) There are trees around the house much taller than the antenna (~60ft vs. 30ft), and a barn 50 ft away with a weather station mast on the roof, also higher than the antenna.

Can anyone suggest some possible reasons why my signal strengths would vary so dramatically over time? I don't have much experience with digital or UHF reception; is this typical?

====================================
UPDATE:

OK, now all signal meters are back up again. Right where they were last night. I swear, I didn't touch a thing, and I'm (pretty sure I'm) not losing my mind.

Any ideas how I can try to stabilize things?

Good News: Not much of a threat wrt overload desensitization.

Bad News: High loss 2Edge paths for ALL digital stations and you need
well over 50 dB dynamic range to receive ABC & CW.

holl_ands, to what extent would antenna directional gain affect Blackduck's situation? That is, would an antenna that's -20dB at 30 deg off axis make it a 30 dB dynamic range problem?

Blackduck,
Those two antennas will interact very little and one or two feet should be OK. If you had to put them nearly touching they would probably still work pretty well.
I use one of the Research Communications preamps and it got me about a 3 dB improvement. When I moved the antenna from about 20 ft above ground to 45 ft I saw a 15 dB improvement.
John

I know that one should keep a minimum of 3 feet between the booms of a uhf and a vhf antenna, but what about a screen type antenna, CM 4228 and a YA1713? Could they be closer without a negative impact on one or the other, if so how close? Also, when combining the two with a CM 7777, would some or all of the 4228's VHF signal be added to the 1713's or would it be lost? ...

There are two ways to look at this.

Antennas react to metal. Even though they're different bands, separate UHF and VHF antennas still see an area neaby that's full of conductors and so reflecting signals. They're both directional antennas, so they're not very sensitive toward the other antenna, but a wavelength or so eliminates the interaction.

Antennas have effective apertures, an area in front of the antenna where any EM radiation of the correct wavelength makes a contribution to the signal in the down lead. The higher the gain, the larger the aperture. You'd like the antenna spacing to be such that the apertures don't overlap.

The recommendation is simple, but the reasoning behind it isn't.

And yes, the CM4228's VHF signal will be lost, but there's not that much there to begin with compared with the YA1713.

Frank

...
This morning, the situation was completely different. Five of the six Syracuse stations had significantly weaker signals, two to the point that I got a black screen. The other Syracuse station was about the same, and oddly enough, so were the Binghamton stations.
...
We did have rain and lightning here overnight. Now I know, the obvious conclusion is something got zapped, but I don't think so, for the following reasons:
...
3) There are trees around the house much taller than the antenna (~60ft vs. 30ft), and a barn 50 ft away with a weather station mast on the roof, also higher than the antenna.

Can anyone suggest some possible reasons why my signal strengths would vary so dramatically over time?
...
Any ideas how I can try to stabilize things?

Tarwater, let me check my understanding. You had picture last night, it rained over night and reception was bad in the morning but improved as the day went on?

It may be the wet trees. Water is bad for reception, and that makes trees a problem. Wet trees are an even bigger problem, but they dry out. Deciduois trees are famous for causing variations; new TV works fine at Christmas but reception dies once the weather gets nice, then comes back in the Fall.

Stablizing unfortuntely may mean height; get above the bulk of the tree mass and not only will signal improve, stability will, too.

Frank

holl_ands, to what extent would antenna directional gain affect Blackduck's situation? That is, would an antenna that's -20dB at 30 deg off axis make it a 30 dB dynamic range problem?

Frank, Can you explain a little bit about what you are asking here? Also maybe you or holl-ands can explain the 50db dynamic range on ABC and CW.
I am currently getting those stations with a RS VU-190, which has a published gain of only 8 dB uhf average. This is why I thought upgrading to a CM 4228 would make some improvement. By the way, I am also able to receive the Fox digital 64.1, (54) a lot of the time. In doing some research on others results in the area, looks like I am doing very well right now. I am just trying to do the best that I can. I really appreciate all of everybody"s help. I have some common sense and a little bit of antenna understanding, but not enough of either, I guess. Walter

Tarwater, let me check my understanding. You had picture last night, it rained over night and reception was bad in the morning but improved as the day went on?

Correct. By early afternoon, all channels were back to last night's levels.

It may be the wet trees. Water is bad for reception, and that makes trees a problem. Wet trees are an even bigger problem, but they dry out. Deciduois trees are famous for causing variations; new TV works fine at Christmas but reception dies once the weather gets nice, then comes back in the Fall.

Yeah, I've experienced that with a satellite dish; weaker signal in the summer when the leaves are on the trees.

But the only trees blocking this antenna are a row of spruce trees around the yard; no seasonal variation there. Other than that, I'm surrounded by hundreds of acres of wide open hay fields and pastures. Could dry vs. wet spruce trees (just a single row of trees) have that much effect? Dropping a signal meter from, say, 80s to 20s?

Stablizing unfortuntely may mean height; get above the bulk of the tree mass and not only will signal improve, stability will, too.


Hmmmm. That's not what I wanted to hear. These are some tall spruces. Don't know how I'd get over them.

Frank, Can you explain a little bit about what you are asking here? Also maybe you or holl-ands can explain the 50db dynamic range on ABC and CW.

I am currently getting those stations with a RS VU-190, which has a published gain of only 8 dB uhf average. This is why I thought upgrading to a CM 4228 would make some improvement. By the way, I am also able to receive the Fox digital 64.1, (54) a lot of the time. In doing some research on others results in the area, looks like I am doing very well right now. I am just trying to do the best that I can. I really appreciate all of everybody"s help. I have some common sense and a little bit of antenna understanding, but not enough of either, I guess. Walter

holl_ands comment was based on your TVFool plots (which I've now closed so this is from memory) that show ~50dB difference between the strong stations at 1-2 degrees and the bunch at 30-35 degrees. ABC and CW are just the weakest at that heading.

A CM4228 has highly directional gain pattern, and is -20dB at 30 degrees off-axis in azimuth (L-R). My question to holl_ands was if that gain difference reduces the dynamic range required.

As is evident in some other threads I'm following, optimium antenna designs are worth 3-6dB in signal, while siting (height) may drive signal 10-15dB and weather (Tarwater's wet trees) another 5-10dB. The advantage of the CM4228 may be it's directional properties rather than raw gain, if dynamic range limitations are the issue.

Or it's directional gain may be it's downfall if it can't get the range of stations the VU190 gets due to it's lower-and-less-directional gain.

Marginal reception is a complex problem with some clear improvements (height always helps), some improvements with tradeoffs - a directional antenna may need a rotor, and some elephants you can't control like the weather.

In ALL cases, the only way to know for sure is to try, and that's what you're doing. Your experiments make you the expert for your house, and hopefully with a little guideance from here, you'll get where you want to be.

Frank

Tarwater,
Conifers hold water like crazy in the rain and snow, but a little wind will dry them out. If you're aimed through them (and it sounds that way from your height comment), it might not be a matter of getting over them but rather aiming though a less-dense portion of the tree, AND gaining all the advantages height brings in weak signal fields, regardless of obstructions.
Frank

Tarwater,
Conifers hold water like crazy in the rain and snow, but a little wind will dry them out. If you're aimed through them (and it sounds that way from your height comment), it might not be a matter of getting over them but rather aiming though a less-dense portion of the tree, AND gaining all the advantages height brings in weak signal fields, regardless of obstructions.
Frank

OK, thanks. Less dense might be tough, because they're right on top of each other. But the mast is only a 5-ft, so I can definitely try going higher. I've resisted a taller mast so far, because the wind really whips across those hay fields. (I had two large, healthy spruces snap off at the base a while back.) I'll need a bigger tripod and some guy wires.

I also need to waterproof the connectors better. I wrapped the connections and the balun well with electrical tape. I was planning to slap some silicone on, once I was convinced everything was stable. Guess I better not wait.

I'm also not sure the balun is meant for outdoor use, so I was going to order a CM3075. Maybe I'll get some Coax-Seal while I'm at it. Not sure if it's better than silicone sealant from the hardware store, but it's cheap enough to try it.

Another possible cause might be that you got hit with a large fluctuation in atmospheric conditions. From your TVfool data, it looks like you have large obstructions (hills) between you and the Syracuse stations. You're getting your signal two ways: via wave diffraction around the tops of the hills, and via atmospheric scattering from water vapor, dust particles, etc. If the atmospheric contribution is important, and it drops sharply because of weather conditions, it can reduce your total signal significantly.

So, what you saw might not be a regular thing, in that it won't happen every time it rains, but you'll get it every once in a while. It happens to me once or twice a month with stations near Charlotte NC (about 70 miles away)

In a more extreme situation, atmospheric conditions can actually refract signals away from your location and cause your signal to drop even if you have line-of-sight to the transmitter. My main stations around Greenville SC are about 50-60 miles away, but they're on top of mountains and I'm down in the piedmont, so I have line-of-sight to them and usually have excellent reception. Nevertheless, maybe once a year they disappear completely for a few hours, and their analog signals become very weak and "snowy."

Hmmmm. That's not what I wanted to hear. These are some tall spruces. Don't know how I'd get over them.

There's always the chainsaw. :D

I don't think that the attenuator idea will work to tame digital multipath. If there is multipath the dynamic equalizer needs a higher signal to noise ratio to decode the signal.

In an analog system the attenuator could bury a ghost in the noise. It wouldn't really eliminate the ghost, but you wouldn't see it either.

Many had good results using attenuators with the initial D* HD Tivo for digital. It has pretty bad multipath performance and is a pretty poor performing digital tuner overall by reputation.

Certainly a more directional antenna, higher f/b ratio, and a better tuner would be the first steps though.

Where are you guys purchasing your dual boom stacking kits? (Horizontal) I see them on the A-Tech Website, yet they never answer their phone. Any other places?

http://www.atechfabrication.com/products/dual_antenna_boom.htm

I made mine mostly. The blonder tongue BTY-B stacking clamp was a welcome addition though and really improved the entire installation considerably. Connecting the stack to the vertical rotator stem seems to be the trickiest part and needs to be sturdy. Fiberglass rods/tubes can be had at http://www.mgs4u.com/fiberglass-tube-rod.htm

I use 1 1/4 tubes with 1 inch tubes telescoped inside for increased stiffness. The center support is regular 1 1/4 CM masting and is coupled to the fiberglass with modified CM attic mounts (seen best end-on in the second pic). The couple b/w the center support and the fiberglass doesn't see as much stress as that of the couple to the vertical rotator stem and has held up well for me. CM attic mounts: http://www.crutchfield.com/S-NNUK1eo5bCG/App/Product/Item/Main.aspx?I=6593078

I am surprised you did not cover the entire reflector with chicken wire.

It was a compromise to decrease overall windload.

cpcat's chicken wire is called hardware cloth in my stores, and it's much finer mesh than you need for Ch 14-52. In the pictured application, it could enhance high frequency gain on an antenna optimized for 800 MHz (Ch 70). That said, it is stiffer than most wire meshs and is well suited to applications with minimal physical support.

Frank

My theory on why the performance is improved is that it improves front/back ratio by blocking signals from the rear. I don't think it helps whatsoever with forward gain. This would seem to jive with what the real world results are as I seem to have much less interference with competing co-channels looking at analog.

There's always the chainsaw. :D

Don't think I'm not tempted! But I need my windbreak. My heating bills are high enough already.

My theory on why the performance is improved is that it improves front/back ratio by blocking signals from the rear. I don't think it helps whatsoever with forward gain. This would seem to jive with what the real world results are as I seem to have much less interference with competing co-channels looking at analog.
not to get off the subject but chicken wire is a 1x2 mesh and hdw cloth comes 8x8 4x4 and 2x2 does opening size matter?

not to get off the subject but chicken wire is a 1x2 mesh and hdw cloth comes 8x8 4x4 and 2x2 does opening size matter?

Assuming that the improvement in performance is simply due to blocking signals from the back, then the smaller the mesh and larger the guage wire the better. However, the smaller the mesh, the more the reflector acts like a sail and thus increasing overall windload on the mast.

I used a galvanized wire mesh with 1/2 inch squares and I'd say the wire itself is around 20 or 22 guage. The screen on the back of the CM 4228 looks to be around 1 x 1/2 so we should be in the ballpark here. See pic below:

http://www.summitsource.com/images/products/AN4228.jpg

Well I tried the it and it was actually pretty good. I had to play around with it as I had problems getting channel 11 (CBS), 13 (SBC), and 20 (MyNetwork/UPN) to play with each other. I'd make an adjustment and to get one and I'd lose one of the other channels. I was finally able to get all of them after a few adjustments. Channel 8 (PBS) was not crystal clear but was more watchable than what I get with the Silver Sensor. I think Channel 8is a VHF station. I also checked the signal strength on the channels and the strength bar was a little longer with this antenna. Oh yeah, it's a GE Antenna. I used it for about 30 to 40 minutes and packed it up to give to my grandfather. It looks like it's a little better than the Silver Sensor but it takes some time playing around with the gain, rabbit ears, and disc to get it working; at least for me it did. I may pick up another later on if I buy another television. I really should have tested it more but I had to drop it off as my grandfather had a broken antenna so he needed a replacement.

http://www.hammacher.com/publish/74605.asp?promo=tested_best_hero

Well, I'm going to try it out anyway. I currently use a Silver Sensor in area code 77429. Overall I'm pretty satisfied with it but sometimes it has a bad day where I have to adjust it multiple times throughout the day. I think it happens more when it's cloudy or raining. Also, channel 8 (PBS) is horrible. I'll compare this to the Silver Sensor and worse case scenario if it's no better I'll just give it to my grandfather as he needs a new antenna anyway; he's in area code 77008. I hope it's at least equal to the Silver Sensor. Anyone in the 77429 area have any antenna's they had great success in using?

Lukes,
If you're still reading, click one of the TVFool.com links and post the .PNG (both today and post-transition) as an attachment tomorrow, after your obligatory 5 (?) posts. Antennaweb is missing a key response - signal level - and is notorious for missing fine details like the low spots you and I live in (but it misses trees and houses). Street address is good, long/lat is better, both truncated in the plot for your privacy.

You've picked a top-line set-up; I bet you realized that TV reception's the same, NTSC or ATSC so everything you know still applies. The only issue I see is tuner overload if you have a close/strong station, and the closest station I see is still 19 miles.

When you get it up, let us know how you fare. The 3671 is one of the few combo units that has a high-gain UHF section, and the H260 is well respected. If you think the puppets looked good, wait until you get a real HD image and display!

Frank

I'm up now. Took Friday off from to setup the chimney mount, mount the masts, mount the rotor, and run the earth grounds.

Good thing I watched the weather. Saturday morning was windy with dew on the roof. Around 10:30 am the roof was dry, but, the wind had picked up and a front was coming. Thunder & lightning and rain by 2:30 pm. Decided to hold off yesterday.

Anyway, pointed antenna initially at 180º to sync the rotor. Then set the antenna to 205º as a go between using the analog signals as a visual verification. Did a digital sweep and got 24 digital channels with 6 of those dropping out some and a couple with pixelation.

No inline attenuator was needed. Because of my local location in a hole an trees all around, seems as though the towers 19 mi. away are attenuated enough with the antenna pointed @ 205º.

Though only presently using a 1996 26" Phillips tube TV at 480i in the great room at this time, the digital OTA signal is crisper than anything I got from D*TV. Only the DVD player gives sharper pictures constantly. The HD OTA programs are just as sharp as the DVD player!!

I figure the 42" HDTV LCD or larger will be on the wall in 18 months or so.

Setup: CM 3671, CM 7777, to in-line gas arrestor, then air gap arrestor on the front end of the 2-way splitter, then MOV surge suppressor on the bus strip. Tuner is a Samsung DTB 260H.

The analog UHF channels (except 17, 22, and 50) still have some ghosting because of the multipath.

Now, digital OTA will be in the mbdrm as soon as those coupons come in in mid-May.

Gonna have to make a decision as to which 2 $20 boxes to get.

Congrats on a successful installation!

I purchased the wire that has 1/4" squares at my local Menard's. (20AWG). I could not see ANY improvement in my reception, except it is like a sail in the air. And by the way, you need a lot of this stuff for the 7' parabolic. (Holy Cow) :D

P.S. The antenna was down for 2 hours, so perhaps the conditions changed.

Any feedback on my tvfool post would be helpful... (See below)

Assuming that the improvement in performance is simply due to blocking signals from the back, then the smaller the mesh and larger the guage wire the better. However, the smaller the mesh, the more the reflector acts like a sail and thus increasing overall windload on the mast.

I used a galvanized wire mesh with 1/2 inch squares and I'd say the wire itself is around 20 or 22 guage. The screen on the back of the CM 4228 looks to be around 1 x 1/2 so we should be in the ballpark here. See pic below:

http://www.summitsource.com/images/products/AN4228.jpg