The Official AVS Antenna Topic! [Text View] - Page 43

ThoraX695

11-07-09, 08:42 PM

I'm not in as bad of a situation as Larry Kenney. However, I'm still 6.4 miles away from the closest transmission tower here in Cincinnati and my strongest station is -19.8 dBm. I'm at about 600 ft. and like to receive stations from Dayton, 40 miles north and right behind an 800 ft. hill. I can sporadically pick up WHIO, WPTD, and WDTN (down to a -10.1 noise margin) with my Clearstream C4 with no tropo and with most of the leaves off the trees. (My C4 seems to have eliminated a lot of multipath that's in my area as well. I'm very pleased with its performance during heavy rain and high winds dealing with my core stations.) I'm assuming that the only hope to improve potential reception to the Dayton stations is to upgrade my antenna to an XG91.

I'm not thinking about upgrading soon though. I have two high-VHF stations to deal with (although WCPO has petitioned to move to UHF). Plus, I'm hoping that AntennasDirect would release a newer version of the XG91 that's cut for UHF 14-51 instead of the current 14-69.

Here's my TV Fool plot (http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dbc27ec0683ac18). I'm open to suggestions!

300ohm

11-07-09, 10:02 PM

Thanks- so the XG91 is poor at receiving those channels?
Well yeah, normally very poor. But as noted on the HDprimer site :
Explanation (non-essential reading)

Why show raw gain when net gain is what is important?

1. If atmospheric noise exceeds receiver noise then the raw gain is what counts. (This is rare for VHF or UHF but does occur in some neighborhoods.)

2. To determine which of two antennas has a narrower beam on a given channel, just compare their gains at that channel. But in this case you use the raw gain, not the net gain. Raw gain is also called directivity.

3. There are cable-matching methods that make the net gain as good as the raw gain for any channel. But while these methods make some channels better, they make other channels worse, and there is seldom an overall improvement. There is presently no hardware available that lets consumers improve the match, except for some indoor antennas.

4. The program that predicts net gain is not very accurate. Net gain is affected by minor details in the way the cable attaches to the antenna. The raw gains are very accurate.

Note that this website is probably alone in using the term “raw gain”. Other references simply call it the gain.

http://www.hdtvprimer.com/ANTENNAS/comparing.html

kevm14

11-08-09, 01:03 PM

Did raising the antenna help any? Remember, you need to find the wave peak along with the height.

With an outdoor antenna, you're going to want a coax ground block (connected to the house electrical ground) between the power inserter and the antenna.

I think it helped but I don't know if I have the patience to try other heights, on top of angles. I was hoping that higher would be better, but with trees that might not necessarily be true I guess.

I should probably add a ground block, though I don't have one at the moment. Do they all pass DC?

Also with the preamp, tell me if my math is correct. 12dB signal gain out of the HDP-269. Let's say 3dB of it is noise (probably somewhat less than that, in reality). That's 9dB net SNR gain when taking into account the noise floor. Subtract another 3dB for cable attenuation (70 feet of RG-6) and that's 6dB net SNR gain to the tuner. Hopefully 6dB (4x) is enough to tune in and stabilize even my 50 mile fringe Boston stations, as well as not over power the tuner on my 19 mile stations. I guess it all depends on what kind of SNR the antenna itself is seeing. If it's marginal then obviously no amount of amplification will help. I remain somewhat optimistic at this point.

hayj

11-08-09, 02:10 PM

I think you'll also see an increase in SNR in the end signal since the tuner will be amplifying less. If your intersted, holl_ands posted this link awhile ago:

http://www.digitalhome.ca/forum/showthread.php?p=879273

On it there's a very useful post that contains a cascaded noise figure calculation spreadsheet. Very helpful to see how various components effect the bottom line.

http://www.digitalhome.ca/forum/showpost.php?p=877838&postcount=605

Digital Rules

11-08-09, 02:51 PM

I should probably add a ground block, though I don't have one at the moment. Do they all pass DC?Yes, you shouldn't really notice much attentuation either.

Hopefully 6dB (4x) is enough to tune in and stabilize even my 50 mile fringe Boston stations, as well as not over power the tuner on my 19 mile stations.I seriously doubt you will see any overload. You can also add a CM distribution amp if you have a few splits in order to maintain adequate gain to each outlet.

I've used this combiantion with an off axis UHF station & 2 FM stations less than 2 miles away. Even the weakest stations 45 miles out are preserved at all 4 outlets.

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dbc27954ffd5063

ctdish

11-08-09, 03:07 PM

Also with the preamp, tell me if my math is correct. 12dB signal gain out of the HDP-269. Let's say 3dB of it is noise (probably somewhat less than that, in reality). That's 9dB net SNR gain when taking into account the noise floor. Subtract another 3dB for cable attenuation (70 feet of RG-6) and that's 6dB net SNR gain to the tuner. Hopefully 6dB (4x) is enough to tune in and stabilize even my 50 mile fringe Boston stations, as well as not over power the tuner on my 19 mile stations. I guess it all depends on what kind of SNR the antenna itself is seeing. If it's marginal then obviously no amount of amplification will help. I remain somewhat optimistic at this point.

The SNR gain using a preamp depends on several things including than preamp gain but in with most UHF TV setups it will be a bit less than the cable loss plus the difference between preamp noise figure and the receiver's noise figure. These are usually about 3 and 6. So the improvement in SNR will less than be cable loss plus 3 which will be less than 3+3=6 dB for your case.
John

Tschmidt

11-08-09, 06:30 PM

I should probably add a ground block, though I don't have one at the moment. Do they all pass DC?
Yes, a grounding block is basically a F connector mounted on a chunk of aluminum so it can be bolted down.

Also with the preamp, tell me if my math is correct. 12dB signal gain out of the HDP-269. Let's say 3dB of it is noise (probably somewhat less than that, in reality). That's 9dB net SNR gain when taking into account the noise floor. Subtract another 3dB for cable attenuation (70 feet of RG-6) and that's 6dB net SNR gain to the tuner.
My understanding is a little different. The noise figure of the amp - reduces antenna effectiveness. So lets say your antenna is rated as 16dBi, if amp noise figure is 3 dB it is the same as if the antenna had only 13 dBi of gain, connected to a perfect amp. Signal captured by the antenna needs to overcome amp noise figure.

Amplifier gain should be set so signal at receiver is about 10 dB higher then preamp input. Only thing amp does is make up for losses that occur after the antenna, it can't create signal if the antenna does not pick it up. The reason for 10 dB figure that is so signal is larger then noise figure of TV, typically about 6-7 dB. That way TV noise figure can be ignored. Upper bound is determined by overload conditions. Too much is as bad as too little.

Thinking about it in other terms hooking TV directly to the antenna reduces antenna's gain by 6-7 dB, since TVs typically have much worse noise figure then a good preamp. Without preamp, even if TV was very close to the antenna, it would effectively be a 9-10 dBi antenna.

Rule of thumb: preamp gain should exceed cable, connector and splitter losses by at least 10 dB. Upper bound is limited by overload but another 10 dB is probably OK unless you have a lot of nearby stations.

kevm14

11-09-09, 08:39 AM

systems2000

11-09-09, 09:22 AM

Connectors are usually calculated at around 0.2 dB.

Tschmidt

11-09-09, 10:04 AM

Well if this HDP-269 only offers 12dB of gain, then I don't see how I could be above that 10dB figure you mention.
You are pretty close with 3 dB cable loss, a few connectors and no splitters.

from the Winegard blurb:
http://winegard.com/kbase/upload/WC-809%20_HDP-269.pdf

It is designed for urban areas, so extremely low antenna signal level is not going to be a problem. Has enough gain to overcome distribution loss.

If your signals are weak, and there are no extremely strong nearby station may want to look into a preamp with better noise figure and more gain. I'm using a CM 7777 feeding an 8-way splitter that adds 11 dB of loss. You may need to add an attenuator to prevent overload.
Or pick a different Winegard preamp:
http://winegard.com/kbase/upload/chart29.pdf

Keep in mind noise figure only comes into play if the signal is very weak. Even if you you don't hit the magic 10 dB value a preamp will still help, it overcomes cable loss and has a better noise figure then your TV.

hayj

11-09-09, 10:07 AM

Well if this HDP-269 only offers 12dB of gain, then I don't see how I could be above that 10dB figure you mention. My cable loss alone is going to be about 3dB. Not sure about connectors (that was a question I had asked previously). I have no splitters, at least. Do you think the HDP-269 is the wrong preamp for me?

Somebody correct me if I'm wrong, but I think your issue is saturating the preamp, much like mine. This is why many use the HDP-269. You don't have to be at the 10 dB mark, but hitting it keeps your tuner's amp (which is assumed to have a higher noise level than the HDP-269) out of the picture. Getting close is still effective. I have a two way split, a jointenna, and about 20 ft of coax. I saw an increase in signal strength and more importantly, a decrease in noise. If your worried about overloading your preamp, you may not have many options.

One thing about this situation I'm still curious about is the dynamic range. It seems like in a situation like this, you get the gain on the high end from the gain of the preamp, but don't you also gain some useful signal on the low end as well by lowering your noise floor, at least as seen from the tuner? If my tuner has a noise figure of say 7dB and I take the tuner's amp out of the picture by getting around 10dB above all losses (say I have 2 dB of loss in the case of the HDP-269), wouldn't the tuner effectively see another 4dB of signal on the low end, increasing my SNR? Could someone clarify this for me?

RocketGuy3

11-09-09, 01:11 PM

IDRick

11-09-09, 02:24 PM

Rocketguy3, you up for building your own? The mclapp 4-bays have moderate high vhf reception and should be able to acquire all your vhf + uhf stations. Check out the thread on this forum "how to build a UHF antenna". Mclapps plans are here: http://www.frontiernet.net/~mclapp/Antennas/diagrams.html

http://www.frontiernet.net/~mclapp/Antennas/

300ohm

11-09-09, 04:41 PM

but I still can't get ABC (RF channel 8). I guess I need a separate VHF antenna afterall, and then a UVSJ combiner.
At 45.5 NM, you should be able to combine cheap rabbit ears with a UVSJ to get that station.

kevm14

11-09-09, 04:59 PM

If your signals are weak, and there are no extremely strong nearby station may want to look into a preamp with better noise figure and more gain. I'm using a CM 7777 feeding an 8-way splitter that adds 11 dB of loss. You may need to add an attenuator to prevent overload.
Or pick a different Winegard preamp:
http://winegard.com/kbase/upload/chart29.pdf

Keep in mind noise figure only comes into play if the signal is very weak. Even if you you don't hit the magic 10 dB value a preamp will still help, it overcomes cable loss and has a better noise figure then your TV.

Here is my TV Fool report (http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dbc272da42d1d2d).

As you can see I have a few strong ones, but I'd also like to consistently receive the 22-34NM range (one is already pretty good, WFXT RF 31 but the rest in that range are in and out). My antenna is fairly high gain (WG-7697P) but I have a bit of a tree problem in my neighborhood. The top 4 stations are why I thought I might need the dynamic range of the HDP-269.

BTW, even after raising my antenna 5 feet to about 20 feet, I still haven't decided on ~32° or 45-50° aim. I have been going back and forth between these. They each have different compromises and I was hoping a preamp would bring in everything from one direction. I am at the 45-50° aim currently, as I have done some aggressive limbing in this direction.

IDRick

11-09-09, 05:10 PM

Kevm14,

In your case, it makes sense to aim the antenna at the lower NM towers (29 degrees, compass heading). It will optimize their received signal while taking away only a small amount from the stronger, closer stations at 41 degrees.

HTH,

Rick

kevm14

11-09-09, 06:08 PM

You'd think so but the tree issue may complicate things. 45-50° is a clearer limb/tree path. I also have a problem with CW RF 22, which is off axis. Aimed at 45-50 it seems to work ok. And there is the ION RF 17 behind me that I'd like to keep. We'll see what happens after I install the HDP-269.

systems2000

11-09-09, 07:18 PM

Hello again guys. So I moved in to my new place, and the DB2 I bought a while back seems to work pretty well for the majority of channels I want... but I still can't get ABC (RF channel 8). I guess I need a separate VHF antenna afterall, and then a UVSJ combiner.

One antenna I was recommended before was the AntennaCraft Y5-7-13, but that seems pretty large for my purposes. Is there anything smaller that would do well enough for me? Here's my TVfool data again:

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d03fbcdecc582ff

Thanks.

You could try building one of Holl_and's circular antennas. The image links were took today, of the one I'm currently getting ready to install. It's a 23" VHF-High, with a 13" spacing to the reflector, and yes, that's a 750ml wine bottle for size reference.

I found that 14.25" of exposed pipe (don't forget to leave enough for inside the corner connectors) at the base (x4) is what gave me the 23" distance on the stand-off brackets. I cut my stand-off brackets at 15" and used plastic siamese cable clamps (which are used to anchor coax) to hold the QICT at 13". My screen is plain galv. 2"x3" fencing. It is 30" wide by 36" high.

I couldn't find corner connectors that didn't have one of the entrances threaded. I used my Dremel, with a sanding drum, to remove the threads.

hayj

11-10-09, 10:54 AM

Anyone have any suggestions for tightening an 91xg to keep it from turning? It's drifted about 45 degrees in the past couple of weeks and is finally affecting the signal. I'm getting up on the roof sometime this week to turn it back and thought I'd have a plan. From what I recall there's just a couple of wing nuts that I hand tightened. I would rather not take it down and make and major changes if at all possible. Any suggestions?

Digital Rules

11-10-09, 11:03 AM

Anyone have any suggestions for tightening an 91xg to keep it from turning?A pair of pliers is all that is needed to tighten the wing nuts. Don't over-tighten them though. Moderate tightening has kept mine in place for 1 1/2 years, even with all the hot air coming from DC.:D

hayj

11-10-09, 11:19 AM

A pair of pliers is all that is needed to tighten the wing nuts. Don't over-tighten them though. Moderate tightening has kept mine in place for 1 1/2 years, even with all the hot air coming from DC.:D

Thanks. I was worried about over tightening, hence the hand tightening. I'll re-aim, hand tighten and then apply a little extra with the pliers. Glad it was that simple.

jpasadena

11-10-09, 12:34 PM

You could try building one of Holl_and's circular antennas.

[snip]

My screen is plain galv. 2"x3" fencing. It is 30" wide by 36" high.

I am getting good results with a similar build - loop with reflector
for VHF-hi. I found that in my situation, a slightly bigger reflector,
48" x 48", got my weakest channel (13) over the threshold.
I haven't seen anyone model how the reflector size affects gain,
and in my case it may just be getting the reflector into some of
the patchy hot spots I am dealing with. Looks like you could still
play around with reflector size at this point in your build.

AntAltMike

11-10-09, 01:59 PM

I see that someone is listing a used ChannelMaster Parascope 4251 antenna on eBay, presently asking $199 but with no bids yet. The bad news is, he is quoting $158 for shipping, though the listing says you can pick it up in New Hampshire (just outside of Concord).

http://cgi.ebay.com/CHANNEL-MASTER-4251-PARASCOPE-UHF-ANTENNA-THE-BEST-UHF_W0QQitemZ230392889622QQcmdZViewItemQQptZLH_DefaultDomain _0?hash=item35a47c8116

I ran his zip code (Contoocook) through TVfool, and with the digital transition, he is in deep doo-doo. Most of what little analog reception he had was VHF, but nearly all of his old VHF stations have relocated to UHF. He had previously been unable to get the popular Boston UHF stations even in analog, and now that they all are UHF, he is getting zilch for Boston reception

RocketGuy3

11-10-09, 03:52 PM

Thanks for the input guys. I tried a bunny ears before, and it didn't work too well, but maybe I need to find the right one or just give it another try seeing as I only need to position it to pick up one channel this time. I hope that works so I don't have to spend money on another antenna.

I get the feeling that TVFool is at least slightly misleading since if the channels really were all coming in that strong, I wouldn't be having this much trouble with ABC. I also have the occasional dropouts on one or two other channels, but I think an amp might fix that.

I probably could/should build an antenna myself, but I'm just too lazy. =P

ziggy29

11-10-09, 05:06 PM

A pair of pliers is all that is needed to tighten the wing nuts. Don't over-tighten them though. Moderate tightening has kept mine in place for 1 1/2 years, even with all the hot air coming from DC.:D
Worked for me, too. At first I only hand-tightened until my fingers hurt, and it didn't take too many windy days to knock it out of whack. When I adjusted it again, I did the same thing but also added maybe another quarter-turn with pliers. That seemed to work fine, as we've had quite a lot of days with 30-50 MPH gusts and it hasn't moved at all since.

kevm14

11-11-09, 04:08 PM

Got my HDP-269 and installed it today (thanks to our veterans of war).

For raw numbers of channels, I tallied 3 different categories.

Total channels and sub-channels received with solid signal: 36
Subtracting currently unused sub-channels: 32
Unused and channels where programming is duplicated (either lower res format or just plain duplicated, across the guide): 26

For example, PBS 2.2 is always a 480 version of 2.1, a 1080i channel.
ABC 6.2 seems to be always a 480 version of 6.1, a 720P channel.
ION 69.1 is a 480 version of ION 68.1.
ION 68.2, 3 and 4 are duplicates of 69.2, 3 and 4, but 69 should be more reliable so I don't need the 68.x's in my guide.

I didn't include channels that share the same network (RI and Boston ABC, RI and Boston CBS, RI and Boston Fox, RI and Boston NBC, RI and Boston CW, etc) because while they MAY share the same prime time programming not everything is the same, so I don't consider them duplicates. The ones above, as far as I can tell, are.

I've got my antenna at about 42°, pointed just to the right of a white pine tree trunk, as that seemed to be the best compromise. Everything is mostly great with just a few fairly infrequent breakups on a few of my tougher Boston channels. I'm a little concerned how this will hold out through next spring as foliage once again thickens but for now things seem nice. At least today. I'll update over the next week or so, because I've seen how inconsistent reception can be on marginal channels, with my tree coverage.

MajesticPete

11-14-09, 12:18 PM

Hi, I'm using a TERRESTRIAL DIGITAL Lacrosse A HDTV Antenna With Amplifier installed on the roof of a 2-floor house.

The setup is coax from antenna (roof) goes to the basement into the amplifier (came with antenna, plugs into the outlet) > into an x8 splitter (LaVa, from ebay, cheap, and covers cable/sat/OTR freq., unamplified) > to TV.

To summarize: antenna > ~60ft rg6 > amp > 1ft rg6 > x8 splitter > ~40ft rg6 > TV.

PROBLEM:
if i use the splitter, i get like 3 channels (of about 15), and all 3 are freezing/pixelerated.
if i remove the splitter (connect from amp rg6 to rg6 that leads up to TV, by using just a regular connector) i get possible channels w/ perferct picture.

Is there any other splitter i should try, or are they all the same?

TIA.
-mp

300ohm

11-14-09, 12:42 PM

Is there any other splitter i should try, or are they all the same?
Do you need an 8X split ? Yeah, I would try a different splitter or use a quality distribution amp.

finlay648

11-14-09, 01:09 PM

rabbit73

11-15-09, 05:13 PM

I have found the Apex DT502 to be very useful when trying to solve OTA antenna problems. It gives not only signal strength but also signal quality. It's a measurement bargain even without the coupon. But, the supply has dried up, so I wanted to try the Centronics ZAT502 HD because it has the the same tuner and dual signal bars. The Centronics is in short supply and I noticed that some Sony TVs have a diagnostics screen mentioned in the pdf manual (http://www.docs.sony.com/release/KDL26L5000.pdf)but no screen shots of it.
I went to a local store to look at the diagnostics screen in the menu of a KDL-26L5000 and then ordered a KDL-22L5000. (The KDL-xxM3000 manual (http://www.docs.sony.com/release/KDL26M3000.pdf) also mentions a diagnostics screen.) The diagnostics screen looks like this:

http://i496.photobucket.com/albums/rr328/rabbit73_photos/IMG_0222_1.jpg

Now that I have all three units I am able to make a comparison using them, a SLM (signal level meter), and a 4-way splitter. My previous tests were done in my car to get away from the street traffic in front of my antenna at home that causes the readings to vary (but the signals stay locked when they are strong) and I was able to drive to strong and weak signal areas. I couldn't work that out because having the 22-inch TV in the car was a big logistical problem. I stayed at home, ran the tests at night with light traffic, and used preamps to vary the signal levels. I also rigged up a mic, amp, and speaker to listen for the traffic to ignore readings when cars were passing by.

The first test used two preamps; a CM7777 near the antenna and a RS 15-1115 inline preamp (one of my better RS purchases) before the attenuator to find out where the signal meters maxed out:
antenna-> 7777-> 50 ft coax-> CM power inserter-> RS amp-> attenuator-> 4-way splitter:

Attn Apex Centronics Sony SLM Equiv
dB Q S Q S S Er SNR dBmV dBm
0 100 87 100 89 79 0 25 +18.5 -30.3
3 100 86 100 89 79 0 25 +15.0 -33.8
6 100 86 100 89 79 0 25 +11.9 -36.9
9 100 86 100 88 79 0 25 +8.8 -40.0
12 100 85 100 88 79 0 25 +5.9 -42.9
15 100 85 100 88 79 0 25 +3.1 -45.7
18 100 83 100 87 79 0 25 0.0 -48.8
21 100 79 100 85 79 0 25 -3.5 -52.3
"Q" is quality, "S" is strength.
Sony IF-AGC figures not listed because in all cases they were the same as strength.

The RS preamp was removed, leaving only the 7777 (my normal setup):
Attn Apex Centronics Sony SLM Equiv
dB Q S Q S S Er SNR dBmV dBm
0 100 84 100 88 79 0 25 +3.0 -45.8
3 100 81 100 87 79 0 25 -0.8 -49.6
6 100 78 100 84 79 0 25 -3.9 -52.7
9 100 73 100 80 78 0 25 -7.0 -55.8
12 100 69 100 76 76 0 25 -10.0 -58.8
15 100 66 100 71 74 0 25 -12.9 -61.7
18 100 62 100 67 71 0 25 -15.7 -64.5
21 100 58 100 63 69 0 25 -18.6 -67.4
24 100 54 100 59 66 0 25 -21.6 -70.4
27 100 49 100 54 62 0 24 -25.4 -74.2
30 100 45 100 50 59 0 23 -28.2 -77.0
33 100 38 100 45 55 0 21 -32.0 -80.8
The 7777 was removed (to simulate weak signals) leaving only the coax between the antenna and the attenuator:
Attn Apex Centronics Sony SLM Equiv
dB Q S Q S S Er SNR dBmV dBm
0 100 55 100 58 66 0 24 -22.0 -70.8
3 100 49 100 53 62 0 24 -25.9 -74.7
6 100 45 100 49 58 0 22 -29.0 -77.8

The RS preamp was inserted between the splitter and the SLM because the meter was near the bottom of scale, and I repeated the test just above. The preamp noise figure does not affect the tuners because it isn't in line with them:
Attn Apex Centronics Sony SLM+amp dBmV corr Equiv
dB Q S Q S S Er SNR dBmV for amp dBm
0 100 54 100 58 66 0 25 -6.1 -22.1 -70.9
3 100 49 100 53 62 0 24 -9.3 -25.3 -74.1
6 100 44 100 49 58 0 23 -12.1 -28.1 -76.9
9 100 38 100 44 55 0 21 -14.9 -30.9 -79.7
12 77 27 65 38 55 0 18 -18.1 -34.1 -82.9
15 26V 0 20V 27 55 0 16 -21.2 -37.2 -86.0
18 dropout dropout 55 3099V 13F -24.3 -40.3 -89.1
A "V" after a figure means that it varies; the Sony errors are updated about once every second. An "F" after the SNR means that the display is frozen at that value. Adding even more attenuation makes the Sony screen go black and say "no signal." At least 15.5 to 16 dB SNR is needed to maintain lock.

When aiming or comparing antennas using the signal strength meter you must keep it below the max value (where your meter doesn't go any higher) by using an attenuator. In my case, that would mean keeping it well below 86 for the Apex, 89 for the Centronics, and 79 for the Sony.

Attachment No. 1 shows a Sony "frozen screen" at 13 dB SNR.
Attachment No. 2 is the RS preamp specs.
Attachment No. 3 is the RS preamp diagram. RS used to print diagrams in the manual, but they don't anymore (http://support.radioshack.com/support_video/doc62/62032.pdf). I think that's a mistake, because showing the diagram encourages experimentation, which means more sales. Looking at the diagram, you can see how the RF signal and the DC power are combined on the coax using capacitors and chokes (inductors). Capacitors pass RF but block DC; chokes pass DC but block RF.

RickCain2320

11-19-09, 01:40 PM

I'm using a trusty old Radio Shack VU-190 in my attic, and due to the preponderance of religious channels and very few secular ones in my area, I would appreciate any tips on getting reception from some of the more remote stations in my area. Pointing the antenna to the close ones is easy since they're clustered in one particular area, but the ones south of me are a bit spread out.

TV Fool Plot attached...

I have a CM4221 laying around unused too. I haven't compared it to the VU-190 yet.

Any help would be appreciated.

300ohm

11-19-09, 03:21 PM

Pointing the antenna to the close ones is easy since they're clustered in one particular area, but the ones south of me are a bit spread out.
You mean those 2 edge, negative NM ones ? You really dont have much (or any) of a chance getting them consistantly with an attic location.

If it wasnt for your channel 7 and 11 stations, the CM4221 would do you fine in a much smaller package than the VU-190. Since those two stations are fairly strong, you may be able to get them with the CM4221 if you electrically attach a couple of 32 - 40 inch rods to the CM4221's reflector. Then you could reclaim a lot of your attic space, heh.

ctdish

11-19-09, 03:26 PM

The signals to the South of you are very weak. If you aim the antenna at them now can you get anything from? This level probably means that with any set up they will not be reliable. You will need a properly aimed outside antenna with a preamp for best results. The preamp requirement along with the very strong signals adds a great deal more difficulty to your problem.
John

RickCain2320

11-19-09, 04:42 PM

You mean those 2 edge, negative NM ones ? You really dont have much (or any) of a chance getting them consistantly with an attic location.

If it wasnt for your channel 7 and 11 stations, the CM4221 would do you fine in a much smaller package than the VU-190. Since those two stations are fairly strong, you may be able to get them with the CM4221 if you electrically attach a couple of 32 - 40 inch rods to the CM4221's reflector. Then you could reclaim a lot of your attic space, heh.

Well I'm not too concerned about Channel 11 but I definitely don't want to lose ABC. I'll swing my antenna south and see what it picks up, if anything. I'm on a hill which does help my reception. I'm in a neighborhood with a property owners association so a roof antenna would result in a huge fight from them.

Thanks for the advice so far, I will post an update on my findings.

hayj

11-19-09, 04:55 PM

I'm in a neighborhood with a property owners association so a roof antenna would result in a huge fight from them.

It probably won't be too huge of a fight when you tell them it's against the law to keep you from putting an antenna on the roof. They don't have the right to stop you.

300ohm

11-19-09, 05:29 PM

Well I'm not too concerned about Channel 11 but I definitely don't want to lose ABC.
Well that even simplifies matters. At a 53.4 NM, the CM4221 may even pick up your channels 7 and 13 as is. With a couple of 36" rods (or door/carpet threasholds or other 36" pieces of metal) horizontally strapped to its reflector, its pretty well guaranteed it will. :)

ctdish

11-19-09, 05:49 PM

He also has a strong channel 13.

IDRick

11-19-09, 06:58 PM

Well that even simplifies matters. At a 53.4 NM, the CM4221 may even pick up your channel 7 as is. With a couple of 36" rods (or door/carpet threasholds or other 36" pieces of metal) horizontally strapped to its reflector, its pretty well guaranteed it will. :)

Interesting comments 300ohm! I want to try this with an mclapp 2-bay (10x9.5) that has a 20" high x 24" wide reflector. It performs very well as a UHF antenna (3 dB less than a 4-bay with reflector). However, high vhf reception on the two bay really takes a hit with a narrow reflector. With that as a preface, where would you mount the rods: 1 each centered behind the elements or some other arrangement?

a8vdeluxe

11-19-09, 08:01 PM

So when is someone going to review the "best indoor antenna every invented by mankind" ?

http://www.avsforum.com/avs-vb/showthread.php?p=17563410

Come on people, what are we waiting for?

link should work now!

300ohm

11-19-09, 08:03 PM

1 each centered behind the elements or some other arrangement?
Yeah. But Im not sure how well the long rods work on all 2 bays. I tried it with a model of the DB2 and the results werent that good. With 4 bays, no problem.

300ohm

11-19-09, 08:05 PM

So when is someone going to review the "best indoor antenna every invented by mankind" ?
Escape Velocity has them reviewed right here :

http://www.avsforum.com/avs-vb/showthread.php?t=1037779

rabbit73

11-19-09, 08:05 PM

a8vdeluxe:
We are waiting for a link that works. Try again.

a8vdeluxe

11-19-09, 08:13 PM

So when is someone going to review "the best indoor antenna every invented by mankind" ?

http://www.avsforum.com/avs-vb/showthread.php?p=17563410

link should work now!

IDRick

11-19-09, 08:59 PM

Yeah. But Im not sure how well the long rods work on all 2 bays. I tried it with a model of the DB2 and the results werent that good. With 4 bays, no problem.

Thanks 300, just looking for your best guess, recognizing that it is guess.

Best,

Rick

IDRick

11-19-09, 09:00 PM

So when is someone going to review "the best indoor antenna every invented by mankind" ?

http://www.avsforum.com/avs-vb/showthread.php?p=17563410

link should work now!

No antenna at your link....

systems2000

11-19-09, 11:48 PM

RickCain2320 (http://www.avsforum.com/avs-vb/member.php?u=8179872),

How many of those analog stations do you want to get? Which stations in particular are you trying to acquire?

Your TVFool data is showing an antenna elevation (AGL - Above Ground Level) of 10'. Is this correct?

With an attic antenna, you're probably not going to get any of the "Tropo" stations.

"2Edge" reception is best accomplished with an exterior antenna and a pre-amplifier that is mounted at least 10' above your roof line.

At 350° (±2°) True, you are getting all the networks there are and most all of your LOS's down to -65.7dBm.

systems2000

11-20-09, 12:06 AM

I've discovered another interesting aspect of my CM3020 setup. When I rotated the antenna (55' AGL) this evening, it affected my portable radio (which was in my office 20' NE of the tower).

This supports the issue I have experienced with the reception off of my other antenna. Is this normal? I was under the impression, that beyond one wavelength, I would not have any interference issues. How do I prevent this from happening to the cut channel antennas I need to install?

300ohm

11-20-09, 10:09 AM

it affected my portable radio (which was in my office 20' NE of the tower).

Which band, AM or FM or SW/other band ? Have you tried moving the portable radio ?

Tower Guy

11-20-09, 11:46 AM

deathnote

11-20-09, 01:19 PM

I'm trying to figure out an antenna to buy for HD.

Here's my tv fool results: http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dbc27b2347973ad

The only channel I care about is ABC channel 9 because it comes in choppy on my direct tv.

Someone on another forum recommended: http://www.amazon.com/Philips-PHDTV1-Silver-Digital-Antenna/dp/B0007XDI54/ref=pd_bbs_sr_1?ie=UTF8&s=electronics&qid=1222980096&sr=8-1

Any advice?

ctdish

11-20-09, 01:41 PM

systems2000

11-20-09, 01:53 PM

Which band, AM or FM or SW/other band ? Have you tried moving the portable radio ?
FM.

I move it all the time. I was just surprised that the CM3020 was affecting another antenna at that distance and now concerned that the antennas I'm looking to mount on the tower are going to be affected.

deathnote

11-20-09, 01:58 PM

Channel 9 is a VHF channel and the Silver Sensor is designed for UHF. An antenna that looks like old fashioned rabbit ears is best for VHF. Since 9 is very strong the rabbit ears will most likely get a strong enough signal but indoor multipath is always a possible and can ruin reception.
John
So, this should work? http://www.bestbuy.com/site/RCA+-+Indoor+Off-Air+HDTV+Antenna/8280834.p?id=1171058630499&skuId=8280834

I want to get something cheap from a local store to try out.

300ohm

11-20-09, 05:28 PM

FM.

I move it all the time.
Hmm, is the FM station pointed in the same direction as the CM3020 is ? If so, since the CM3020 is a UHF/VHF/FM antenna, you could tap into it for additional gain.

ctdish

11-20-09, 06:01 PM

So, this should work? http://www.bestbuy.com/site/RCA+-+Indoor+Off-Air+HDTV+Antenna/8280834.p?id=1171058630499&skuId=8280834

I want to get something cheap from a local store to try out.

For an indoor channel 9 antenna it is probably as good as any small antenna. Your signals are probably strong enough for it to work on UHF channels. For $9 it is not a big investment. The silver sensor would reduce multipath on UHF and and get more signal.
John

systems2000

11-20-09, 06:35 PM

Hmm, is the FM station pointed in the same direction as the CM3020 is ? If so, since the CM3020 is a UHF/VHF/FM antenna, you could tap into it for additional gain.
I'm not looking to tap into the CM3020, I'm trying to discover why it is throwing out such a large/wide interference fiield. I don't need more issues with my reception and I definitely don't need the CM3020 limiting the reception capabilities of my cut channel antennas.

I already have a dedicated FM antenna (on the far side of the house), which feeds the audio tuner.

Tower Guy

11-20-09, 08:00 PM

For an indoor channel 9 antenna it is probably as good as any small antenna. Your signals are probably strong enough for it to work on UHF channels. For $9 it is not a big investment. The silver sensor would reduce multipath on UHF and and get more signal.
John

Agreed. I don't like indoor antennas, but that is the right one for VHF stations.

Don F.

11-28-09, 06:20 PM

I am getting the bug to combine two xg91s to try to improve my signals from Atlanta some 80 air miles way. Presently I use a single xg91 for uhf and plan to install another fairly soon, but need some help on a good combiner. I am removing my ya1713, as I have not been able to receive a usuable signal from WXIA dt 10, and could use the antenna else where.
After combing the the uhf s they would connect to a cm7777, which has been in use with my current setup... I looked at Solid Signal, but the only thing I saw had a 3.5 db reduction in gain..
Thanks for any help...

scottmo2020

11-29-09, 09:19 PM

I am having major problems receiving VHF OTA, which is not a big surprise considering the many issues already brought up with digital TV on VHF. Here is a quick run down and I am hoping for any ideas!

My TV Fool:
http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dbc273f8529f405

I have a Channelmaster 4228 (old version) with a Wineguard AP-8275 preamp to receive KOLR on VHF 10 (UHF is great!) I get about 80-84% signal strength, but I have so much interference from something it is not watchable. I am also trying for KRCG VHF 12 with a Wineguard YA 1713 and Wineguard 3700 VHF only preamp (not at the same time). KRCG comes in 90%+ but is also unwatchable with interference. Even KOMU comes in at 80%. Most of the time the signal is jumping all over the place though, and I think I am getting outside electrical interference.

I connected my system direct to a TV testing in the garage, and turned all of my circuit breakers off except for the one in the garage and the interference was still there. Also, when it rains outside my interference seems to go away and all VHF stations are pretty solid. It leads me to think it is something electrical outside. I am going to see the power company and see if they will help me.

I also have a 10kw FM station 1.1 miles from me and used the FM traps on the preamps, and separate FM traps. I have had this setup for over a year though and have not had trouble except for the past few weeks.

I guess the short version of my question, is there something that can filter out that kind of noise? I already have the ground block on my coax and such. I am using two different antennas, preamps, feedlines, and pointed nearly 180 degrees different, and the antennas are in two different locations about 30 feet apart. I might just be out of luck but I'm open to any ideas.

Thank you!

rabbit73

11-29-09, 10:21 PM

scottmo2020:
Your tvfool link doesn't work; it only takes us to the start page rather than your report page. Please try again and use the link in bold type near the top of the report page.
I connected my system direct to a TV testing in the garage, and turned all of my circuit breakers off except for the one in the garage and the interference was still there. Also, when it rains outside my interference seems to go away and all VHF stations are pretty solid. It leads me to think it is something electrical outside. I am going to see the power company and see if they will help me.
It sounds like power line noise.
I guess the short version of my question, is there something that can filter out that kind of noise?Since the noise exists on the channel, anything that filters out the noise will also filter out the signal. It must be eliminated at the source.
Is there any way I can hunt down the source of the interference? I don't know if it is in my house, but I don't think so. No new gadgets, appliances, fluorescent lights, any of that. I mentioned before it seems to get better when it rains. Maybe the electric company could help? I'm afraid I am pretty much out of luck for CBS OTA.The ideal tool would be a spectrum analyzer, but they are expensive and not many people have one. It would allow you to see the signals and the noise at your problem frequencies. You can track down the noise using a portable receiver that can be set for AM and will tune the VHF band. A handheld directional antenna could be connected to the receiver and aimed at the suspected areas. This is called DF (direction finding). Do you know any hams that could help you?

If the interference is coming from the power lines, the power company is responsible for fixing it because you are probably not the only person who is being affected. The FCC says that they cannot charge you for fixing it. It is also a safety and reliability issue so the power company should want to fix it in the first place. It's usually caused by bad "hardware." Don't try to fix it yourself or go banging on power poles if you think you have located the power line source of the noise.

scottmo2020

11-29-09, 10:30 PM

rabbit73

11-29-09, 11:05 PM

dr1394

11-29-09, 11:19 PM

scottmo2020

11-29-09, 11:21 PM

That's better, Scott. If you had used exact address (which doesn't show in the result) or coordinates (the last digits are deleted) the report would have been more accurate, but that might not matter too much if you are out in the country.

At -54.1 dBm KOLR is quite strong, so your interference must be severe. KRCG, at -73.2 dBm and 1edge is a lot weaker.

I assume that your antennas are outside, rather than in an attic.

I used your zip code to generate an fmfool report, which is in the attachment. KCVO is very strong. Lately, some people have been troubled by the second harmonic (2x the FM frequency) of FM signals which fall in the VHF-hi band that an FM filter doesn't always eliminate.

Hi,
Thanks a lot for your help. I updated my TVFool using my coordinates from my GPS. The results seem strange because KYTV I can receive around 80%, KSFX is 92% and KSPR is around 90%, but the report shows they should be pretty weak.

I am down in a hole somewhat, about 100 feet below my surroundings to the southwest where my Springfield MO stations are. GPS shows me at 780 feet, and the antenna is on a 5 foot pole on the 2nd story of my house outside.

That radio station is very strong, because I hear it bleed on my cheaper FM boombox and kids portable radios. But that station has been around awhile and I have just started having problems in the last few weeks.

I'm going to call the power company and see what they can do. I am a amateur radio operator and know a couple people who might be able to help!

Thanks again
Scott

Tower Guy

11-30-09, 09:26 AM

It leads me to think it is something electrical outside. I am going to see the power company and see if they will help me.

You can verify electrical interference with your AM car radio. Start when it's light out. (to avoid skip) Tune to an unused spot on the low end of the dial. (530-600) Drive near your house. If you hear a loud buzzing, you have proven power line noise.

kevm14

11-30-09, 03:12 PM

I'm back.

After living with the WG HDP-269 preamp for a while I am mostly doing well, but still having troubling variations in reception quality on some stations, with one station still being a big nuisance to receive well.

As a refresher, here (http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dbc272da42d1d2d) is my TV Fool. The station that is being the biggest pain is WSBK RF 39. I regularly get 2 channels below this one in predicted signal strength and sometimes 3.

I was thinking about things that could be hurting me after reading Antenna Basics (http://www.hdtvprimer.com/ANTENNAS/basics.html). I will try the AM radio trick for power line interference. I also can't shake the idea that strong FM stations (http://kevinallenmoore.com/photo/v/misc/ATSC/Radar-FM.png.html?g2_imageViewsIndex=1) could degrade the performance of the pre-amp. I even briefly considered stacking another antenna (I have a WG 7697P).

The other thing I was refreshed on after reading the Antenna Basics page, is the idea that I want to compensate for my cable loss plus another 10dB, I guess to minimize the receiver's AGC compensation. With my WG HDP-269, which specializes in high dynamic range but has less gain than the stalwart CM 7777, I am wondering if I should try another pre-amp. I have about 70 feet of quad shield RG-6, so I estimate my average loss to be around 3dB. The HDP-269 is 12 dB with 3dB noise, so I am right around 9dB after cable losses. Would the CM 7777 work better for me?

lovebohn

11-30-09, 03:33 PM

What is the AM radio trick?

Sorry, found it two replies above.

Don F.

11-30-09, 03:51 PM

Here's some actual measurements:

http://www.antennahacks.com/CombinerComparison.htm

Ron

Looks like it would be more work than I am looking for, with no gurantees for improvement, Thanks for the info...

rabbit73

11-30-09, 04:06 PM

scottmo2020:

Tower Guy is correct, the AM broadcast band can be used if the interference is strong. If you use a hand-held portable radio its built-in ferite loopstick antenna is bidirectional.

73,
rabbit

lovebohn:

What is the AM radio trick?
An AM radio must be used to track down broadband interference because FM is resistant to noise.

scottmo2020

11-30-09, 04:21 PM

You can verify electrical interference with your AM car radio. Start when it's light out. (to avoid skip) Tune to an unused spot on the low end of the dial. (530-600) Drive near your house. If you hear a loud buzzing, you have proven power line noise.

This morning around 7:45am I left the house for work and tuned to 530 AM. I heard a loud buzzing sound at least a half a block down the street and then it went away. I heard some alternator noise but the loud buzz was gone.

I put a call into my electric company and spoke with a guy who seemed to understand what I was saying! I told him about my AM and VHF woes and explained I killed the power to my house and the interference was still there. Here's to hoping they find something!

dr1394

11-30-09, 04:54 PM

An AM radio must be used to track down broadband interference because FM is resistant to noise.
That's correct, but using a broadcast band (530 to 1700 kHz) radio is too "blunt" of a tool. The noise gets conducted down the wires, and it's too difficult to pinpoint the source. The way the professionals (the guys at the power companies) track down interference is with a VHF/UHF radio that has an AM mode. The trick is to keep going up in frequency so that the individual power pole can be identified.

I use an Icom IC-T8A handheld that receives the 118 to 136 MHz aircraft band (which still uses AM modulation). By just walking around the neighborhood, I can usually find the offending pole (and specify the pole number when making a complaint).

Ron

rabbit73

11-30-09, 07:03 PM

This morning around 7:45am I left the house for work and tuned to 530 AM. I heard a loud buzzing sound at least a half a block down the street and then it went away. I heard some alternator noise but the loud buzz was gone.

I put a call into my electric company and spoke with a guy who seemed to understand what I was saying! I told him about my AM and VHF woes and explained I killed the power to my house and the interference was still there. Here's to hoping they find something!
I hope you have better luck than some other hams.

ARRL has an article about a long-term problem with Duquesne Light Company in PA:
FCC to Utilities: Don't Look to Hams to Pay for Your Testing

http://www.arrl.org/news/stories/2009/08/27/11043/?nc=1

Digital Rules

11-30-09, 07:38 PM

I'm back.

After living with the WG HDP-269 preamp for a while I am mostly doing well, but still having troubling variations in reception quality on some stations, with one station still being a big nuisance to receive well.
If you are only running one tuner off the pre-amp, adding more gain will not help with only 70 feet of cable. Multiple splits would benefit most with the addition of a quality distribution amp in conjunction with the pre-amp. If you have already played around with height & aiming tweaks, the only solution may be a higher gain UHF only antenna to augment the 7697.

I also seriously doubt that FM or electrical interference are affecting your nuisance UHF channel. I feel you simply need more antenna gain by finding a better sweet spot or a "separate" UHF antenna.

kevm14

11-30-09, 08:16 PM

If you are only running one tuner off the pre-amp, adding more gain will not help with only 70 feet of cable. Multiple splits would benefit most with the addition of a quality distribution amp in conjunction with the pre-amp. If you have already played around with height & aiming tweaks, the only solution may be a higher gain UHF only antenna to augment the 7697.

I also seriously doubt that FM or electrical interference are affecting your nuisance UHF channel. I feel you simply need more antenna gain by finding a better sweet spot or a "separate" UHF antenna.

You are probably right. It is frustrating though, because some recordings from this channel are almost perfect but some are completely unwatchable, with 5-15 seconds of blackness between bits of pixels.

I raised it another 5 feet within the past few weeks, making it 20 feet off the ground. I still have a tree problem, of course, but short of spending another $700 to remove a big white pine, there is nothing else I can do on my property. I've limbed it to probably 30+ feet.

The current aim is at about 42° IIRC, just to the right of the big white pine trunk, which means there could be some sort of multi-path problem. Perhaps the ideal aim actually changes and each time I have a problem, there is some new ideal aim for that particular condition.

The WG 7698P has maybe 1dB of additional gain on RF 39. I kind of wish I just went straight for that monster so I wouldn't wonder. But I think my mast would be borderline inadequate for that guy. Like you say, maybe adding a high gain UHF antenna and combining would be best for me. As good as the 7698P is (12-14dB @ UHF), the UHF-only antennas do an even better job at UHF, I think.

EDIT: One easy thing I could try is lowering the antenna on the mast. I haven't tried that since getting the pre-amp.

300ohm

11-30-09, 11:01 PM

One easy thing I could try is lowering the antenna on the mast. I haven't tried that since getting the pre-amp.
Yep, sometimes even as little as 6" up or down can make a significant difference on uhf channels. Other relatively easy ideas are tilting the antenna a bit, and moving the whole antenna and mast to different mounting locations.

systems2000

11-30-09, 11:15 PM

Other relatively easy ideas are … moving the whole antenna and mast to different mounting locations.

As I noted in my post awhile back on kevm14's system.

kevm14

12-01-09, 09:42 AM

Moving the whole thing is more work than I care to take on currently. I'd have to poke new holes in my siding and sheathing, for starters. I already tried raising it 5 feet, so now I'll experiment with heights in between. Not sure how to tilt it, though that seems like a good idea, too.

scottmo2020

12-01-09, 11:54 AM

I hope you have better luck than some other hams.

ARRL has an article about a long-term problem with Duquesne Light Company in PA:
FCC to Utilities: Don't Look to Hams to Pay for Your Testing

http://www.arrl.org/news/stories/2009/08/27/11043/?nc=1

The electric company came out today and didn't find anything creating noise. The guy was very helpful but couldn't find any power line or transformer noise. Oh well. I guess my VHF viewing days are over. It is too bad the FCC let themselves get run over by broadcasters looking to save a few bucks on their electric bill and allowed VHF digital TV in the first place. It just doesn't work. :mad:

Who cares about a few hundred hillbillies like me that live on the fringe anyway. ;)

un43

12-01-09, 12:03 PM

I would like some comments on my proposed setup. I live 50 miles NE from the towers in Dallas, in a low area next to a creek. The antennas will be stacked on a mast that is about 5 feet above the tripod roof mount. Height of the top antenna will be about 25 feet from the ground. Here's what I'm planning:

UHF: Winegard HD-8800
VHF: AntennaCraft Y5-7-13
Preamp: Winegard AP-2870 with separate UHF/VHF inputs

Here are my results from tvfool: tvfool. c o m/?option=com_wrapper&Itemid=29&q=id%3dbc27b824542341

Should I expect good reception 50 miles out with this setup? The channels I am mostly interested in are for the major networks (ABC, NBC, CBS, PBS, FOX). You can also see that there is a local station only a few miles away in the same general direction. Should this cause any reception problems with a preamp? I am also considering the following as alternatives:

UHF: Antennas Direct 91XG
VHF: Winegard YA 1713
Preamp: Channel Master CM 7777

Thanks for any feedback.

IDRick

12-01-09, 12:43 PM

un43,

Here is the link to your tvfool: http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dbc27b824542341

Based on the projected signal strengths at your location, I would go with your second option (XG-91, YA1713, and CM7777). You do not have strong nearby channels so there is no problem using the CM7777 at your location. Antennas in your second option have higher gain than those in your first option. You will need the higher gain that option 2 provides.

Here is a link to a comparison between the XG-91 and the Winegard 8800. (see: http://www.antennahacks.com/AntennaComparison.htm)

HTH,

Rick

Tower Guy

12-01-09, 01:02 PM

I would like some comments on my proposed setup.

I think that either system will work.

The first one is cheaper and smaller.

The second one will have fewer drop-outs on the weakest channels.

If you want a second CBS you could add a Y10-7-13 aimed at 336 degrees and a Jointenna for channel 12.

rabbit73

12-01-09, 01:27 PM

The electric company came out today and didn't find anything creating noise. The guy was very helpful but couldn't find any power line or transformer noise. Oh well. I guess my VHF viewing days are over. It is too bad the FCC let themselves get run over by broadcasters looking to save a few bucks on their electric bill and allowed VHF digital TV in the first place. It just doesn't work. :mad:

Who cares about a few hundred hillbillies like me that live on the fringe anyway. ;)
Sorry to hear that he couldn't help you. It is the perverse nature of intermittent problems not to act up when the "expert" is checking on them.

Other sources can make noise that sound like power line noise.
I encourage you to do a little more hunting with a portable radio or a borrowed HT that dr1394 mentioned that will tune AM VHF.

300ohm

12-01-09, 01:41 PM

It is the perverse nature of intermittent problems not to act up when the "expert" is checking on them.
Quantum physics strikes again, heh.

Not sure how to tilt it, though that seems like a good idea, too.
Most antenna ubolts will have enough play in them for about 10 degree tilts. Loosen, tilt, and retighten.

Tower Guy

12-01-09, 02:08 PM

The electric company came out today and didn't find anything creating noise. The guy was very helpful but couldn't find any power line or transformer noise. Oh well.

I'd guess that you have interference that the technician couldn't find.

Some troubleshooters are better than others. Here's one guy who uses multiple tricks. http://www.enerchecksystems.com/articl15.html

Once you're sure that there is a real problem don't hesitate to call multiple times. Be kind, but persistent.

Sometimes I find the bad pole for the power company. You may find multiple peaks as the signal travels along the wire. Once you've found the general location using 530 KHz, try again at 750-800, once more at 1100, and again at 1610. It is likely that the noise peaks will move around except for a single location which will be the bad pole.

A police scanner that can tune the airplane band is also a good suggestion.

Occasionally your ears can hear arcing.

un43

12-01-09, 02:28 PM

Here is a link to a comparison between the XG-91 and the Winegard 8800.

Thanks for the replies. After checking the link, I'm now leaning toward either the 4228 or 91XG. I am hesitant to install a 4228 with a VHF antenna on only 5 feet of mast length, so I will probably go with the 91XG.

300ohm

12-01-09, 05:35 PM

I'm now leaning toward either the 4228 or 91XG.
The old CM4228 is hard to get now. The new CM4228HD isnt as good as the old CM4228, unless you do some hardware hacks on it.
http://www.hdtvprimer.com/ANTENNAS/TemporaryPage.html

Another comparison of the CM4228 vs the XG91
http://www.hdtvprimer.com/ANTENNAS/comparing.html

I am hesitant to install a 4228 with a VHF antenna on only 5 feet of mast length, so I will probably go with the 91XG.
They are both uhf antennas, and I would think the XG91 would make the mast a bit more off balance than the CM4228, although neither should be that much of a problem.

scottmo2020

12-01-09, 05:38 PM

I'd guess that you have interference that the technician couldn't find.

Some troubleshooters are better than others. Here's one guy who uses multiple tricks. http://www.enerchecksystems.com/articl15.html

Thanks! I am going to try those suggestions and see if I can narrow it down. He didn't spend much time looking around, not too much effort but at least someone tried.

On another note, a friend of mine is considering getting an antenna. He's much closer to the Springfield market than I am. He will be going 75 feet or so to a single TV set. Here is his tvfool:

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dbc27f730bf3780

I was thinking about the AntennaCraft HBU33. The HBU44 seems overkill. I also don't think he would need a preamp off the bat unless his run is longer or has more splits.

Thanks again!

ProjectSHO89

12-01-09, 06:17 PM

Thanks! I am going to try those suggestions and see if I can narrow it down. He didn't spend much time looking around, not too much effort but at least someone tried.

On another note, a friend of mine is considering getting an antenna. He's much closer to the Springfield market than I am. He will be going 75 feet or so to a single TV set. Here is his tvfool:

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dbc27f730bf3780

I was thinking about the AntennasDirect HBU33. The HBU44 seems overkill. I also don't think he would need a preamp off the bat unless his run is longer or has more splits.

Thanks again!

Try AntennaCraft... His local Radio Shack should have it if he doesn't want to wait for shipping and he doesn't mind paying retail.

scottmo2020

12-01-09, 06:44 PM

Try AntennaCraft... His local Radio Shack should have it if he doesn't want to wait for shipping and he doesn't mind paying retail.

Oops, thanks. I fixed my post. I was looking at 900 different antennas all at the same time!

Tower Guy

12-02-09, 11:31 AM

I was thinking about the AntennaCraft HBU33. The HBU44 seems overkill. I also don't think he would need a preamp off the bat unless his run is longer or has more splits.

If aimed at 200 degrees the smallest HBU-22 would still get plenty of signal even without a preamp.

craftech

12-03-09, 09:06 AM

systems2000

12-03-09, 09:50 AM

How is reception of the UHF channels?

You also have channel 7 at a higher signal level and channel 11 at just a bit lower (from 13) and they are all at fairly strong levels. I think that if you made a simple folded di-pole antenna for channel 13 and placed it on the roof with the UHF antenna (combine that with a UVSJ), you should be able to get all three.

The CM7777 is probably way more than you really need. Also make sure your compass is accurate and that your antennas are flat faced towards 237° Magnetic.

IDRick

12-03-09, 11:00 AM

I was wondering if someone can help me with this.

I have cable so this is for my mother who does not. She lives an hour away from me. This is her TV Fool result:

http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d7721428244f26c

Two years ago I put a DB2 on the roof of her two story house and ran it down into her TV room. I also put a popular Radio Shack Indoor VHF/UHF antenna on top of her TV (it has an indoor/outdoor switch).

The setup doesn't always work so well.
After the transition we found out that some of the channels went VHF which negates the roof antenna (DB2). PBS (13) went VHF and doesn't always come in (she loves that station). The RS indoor antenna is probably too low to the ground for reliable VHF reception.

I bought a CM 7777 amp, but before I crawl up there to install it ( the roof is really steep), I was wondering if that amp will be enough. After all, the DB2 is UHF only.

And does that amp HAVE TO go on the roof? Can't it go indoors?

Can I maybe add homemade "rabbit ears" to the DB2 for VHF,

or should I get an entirely different antenna?

Or perhaps something else I could do?

Thanks,

John

John,

The CM 7777 is a top line pre-amp but it is *not* designed to be used in locations closer than 30 miles from the towers. You have *too* many strong signals and will overload the CM 7777. Overload reduces and/or eliminates reception. An HDP269 is a better choice in pre-amp for your location.

You could try mounting the antenna up in the attic, assuming your roof is a plywood deck + asphalt shingles. You'll need to try several locations to find the hotspot. Avoid any locations where you have nearby metal ductwork, aluminum insulation or electrical wiring. Use the DB-2 for UHF and a set of rabbit ears for VHF. Join the DB-2 and rabbit ears together with a UVSJ before connecting to the HDP269. (see: http://www.solidsignal.com/pview.asp?p=uvsj&d=Pico-Macom-UVSJ-UHF-VHF-Band-SeparatorCombiner-forAntenna-(UVSJ)&sku=UVSJ&mc=03).

Alternatively, I would consider purchasing a HBU-22. This will have higher gain on UHF than the DB-2 and also receives high vhf band stations. It would work well on the roof or in the attic.

A second alternative is to build a 4-bay mclapp DIY antenna. Diagrams are here: http://www.frontiernet.net/~mclapp/Antennas/DIY%20TV%20Antennas.html See the thread on this forum entitled "How to build a UHF antenna". mclapp posts frequently on this forum. The mclapp four bay receives high vhf and uhf channels. I build mine using pvc. My estimated cost for a mclapp with a reflector totals $30 assuming you need to buy everything. If you put it up in the attic, you can use a piece of card board covered with aluminum foil as a reflector rather than buying a 36" x 40" piece of hardware cloth.

HTH,

Rick

scottmo2020

12-03-09, 11:54 AM

I use an Icom IC-T8A handheld that receives the 118 to 136 MHz aircraft band (which still uses AM modulation). By just walking around the neighborhood, I can usually find the offending pole (and specify the pole number when making a complaint).
Ron

I wanted to run one other question by the experts to get opinions. My YA1713 VHF only yagi is installed on an old DirectTV J mounting pole toward the bottom of the roof. So essentially the back of the yagi is only a few inches from the roof, on a 5 foot pole pointing toward the TV stations. Do you all think the antenna could be picking up signals bounced off the roof causing multipath or other problems? Here is a (very) crude drawing of the peak of the roof if you imagine looking at it from the side. I can take a picture if that might help.

^
/ \
/ \---> TV Stations
/ \|
/ \

Hope that makes sense!

ProjectSHO89

12-03-09, 12:14 PM

300ohm

12-03-09, 02:54 PM

Do you all think the antenna could be picking up signals bounced off the roof causing multipath or other problems?
Whats the roof made of ? Actually, a lot of newer asphalt shingle roofs contain tiny bits of metal shreds in them (that stick in your hands, heh) that could well affect the antenna performance when mounted too close.

scottmo2020

12-03-09, 04:09 PM

Whats the roof made of ? Actually, a lot of newer asphalt shingle roofs contain tiny bits of metal shreds in them (that stick in your hands, heh) that could well affect the antenna performance when mounted too close.

That is a good question. The house is 6 years old with asphalt shingles. I would guess my contractor used low to mid-grade regular residential stuff and nothing too fancy like special energy efficient blah blah...

Scott

300ohm

12-04-09, 03:30 PM

I would guess my contractor used low to mid-grade regular residential stuff
That stuff can have the tiny metal shards in it too, as I found out, heh.

craftech

12-04-09, 06:47 PM

Systems2000, Rick, and ProjectSHO89..............

Thanks you so much for the help. You guys are great. I really appreciate the time you spent to help me.

Regards,

John

systems2000

12-04-09, 10:24 PM

Did you produce a solution and, if so, how did it come out?

Vidop

12-06-09, 04:13 PM

First time posting to this thread--Next spring, I'll be moving to LaFayette, Indiana (47909). I'll be putting up a CM 4228 (old, original style) at ~28' height. I've checked TV Fool and see that the Indianapolis stations I want are ~45-55 miles away, 130 degrees (true), mostly two edge reception (some are one edge). By looking at their chart, I think I can get by without a pre-amp. But, if I do need a pre-amp, there may be a problem. There is one local station (WLFI) located only fourteen miles away. It is at a heading of 67 degrees (true) vs. the 130 degrees of the Indy stations. If I do need a pre-amp, would WLFI overload the pre-amp at that close of a range even though their xmtr is almost sideways to the way my antenna would be pointing (67 degrees vs. 130 degrees)? If it might overload, does anybody have a suggestion of how to negate this? Thanks for the info.

BCF68

12-06-09, 04:27 PM

Tower Guy

12-06-09, 07:45 PM

If it might overload, does anybody have a suggestion of how to negate this? Thanks for the info.

Use an AP-4700 UHF only preamp. (Or an AP-2870 with nothing connected to the VHF input.) Get a Y5-7-13 for WLFI. Add WLFI after the preamp with a UVSJ or channel 11 Jointenna. You won't get WISH with the UVSJ, you might with the Jointenna.

If you want to amplify WISH there's another, but more complicated trick with multiple Jointennas or a third antenna.

systems2000

12-06-09, 07:54 PM

I have three stations (within 20 miles of my location) that are reaching me with levels of -31.5 to -37.0dBm and I'm using a pre-amp on a deep fringe VHF/UHF/FM antenna and still lock stations down to -110.7dBm.

Look at acquiring a UHF only pre-amp and get yourself a VHF-hi antenna. Combine this with a UVSJ.

NOTE: I see Tower Guy (http://www.avsforum.com/avs-vb/member.php?u=7433992) got his post in before mine. ;)

systems2000

12-06-09, 09:21 PM

I use a homemade circular antenna (w/ reflector) for a station (W08EE-D) that is 34 miles LOS and a receive level of -67.3dBm. The cable run goes through a UVSJ and 182' RG-6 to my 901. It doesn't have a pre-amp and is fairly stable.

Vidop

12-08-09, 11:39 AM

Thank you to all that responded to possible pre-amp overloading in relation to my future antenna in LaFayette, Indiana. When I am moved and settled in (next year), I'll get my tower put up. And, I definitely will try your suggestions. Once again-thank you.

aero12

12-08-09, 09:31 PM

guys. here is my TVfool (http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d7721f57b61e8b3).

I am dropping cable so would like to get as much as possible.

I am in a multi level building with roof about 40 above ground level.

The problem is there are buildings that rise higher:
1) most problematic it seems will be a building about 200' away blocking line of site to local network stations. the building is at 300 to 330 degrees and about 80' tall. The local (DC) stations are close but there is definitely a building in the way
2) another building at 340 to 30 degrees that rises to 100'
3) one at 30 to 60 degrees that rises to 120' (blocking line of site to Baltimore which are the second set of stations.)
4) and one at 130 to 180 degrees that rises to 200'

cabling aside is there some good advice for antenna in the $100 range? I could go 10' above my own roof line giving me about 50' AGL.

I'd like to do the best I can without trying 15 antennas! Any advice for this close but no line of sight situation?

scottmo2020

12-09-09, 10:05 AM

aero12

12-09-09, 01:41 PM

I'm no expert, but it seems being that close and with those signal levels a simple non-amplified set of rabbit ears would work well! Baltimore would be more of a challenge though.

Nope. building's construction and placement of AV have always made that a problem.

Point is it is easy for me to mount an antenna on the roof, be 50' above ground, I already have the roof wired with good quality rg6 which runs to two rooms with TVs and I don;t mind spending $50 to $100 on a roof antenna.

the question is what is best roof antenna wiht my tvfool report given that even 50' above ground is disrupted by nearby three 80' buildings

klandry7

12-09-09, 05:28 PM

Nope. building's construction and placement of AV have always made that a problem.

Point is it is easy for me to mount an antenna on the roof, be 50' above ground, I already have the roof wired with good quality rg6 which runs to two rooms with TVs and I don;t mind spending $50 to $100 on a roof antenna.

the question is what is best roof antenna with my tvfool report given that even 50' above ground is disrupted by nearby three 80' buildings

The Channel Master 4228HD is $75 with free shipping on Amazon right now.

goldrich

12-09-09, 05:59 PM

The Channel Master 4228HD is $75 with free shipping on Amazon right now.

The Channel Master 4228 UHF antenna was a very good model, but please be aware of some of the negative reviews relating to the new but supposedly not improved 4228HD.

http://www.hdtvprimer.com/ANTENNAS/TemporaryPage.html

http://www.hdtvprimer.com/ANTENNAS/comparing.html

As close as aero12 is to the locals, there could be some multipath issues, especially with the nearby tall buildings. If so, per info at hdtvprimer and from personal experience @ 3-5 miles from local stations, a Yagi antenna, like the Antennas Direct XG91, would do more to tame multipath. If you need lots of gain for the higher UHF channels, like 35-51, the XG91 should be a little better match. My 2 cents.

Steve

klandry7

12-09-09, 06:38 PM

The Channel Master 4228 UHF antenna was a very good model, but please be aware of some of the negative reviews relating to the new but supposedly not improved 4228HD.

http://www.hdtvprimer.com/ANTENNAS/TemporaryPage.html

http://www.hdtvprimer.com/ANTENNAS/comparing.html

As close as aero12 is to the locals, there could be some multipath issues, especially with the nearby tall buildings. If so, per info at hdtvprimer and from personal experience @ 3-5 miles from local stations, a Yagi antenna, like the Antennas Direct XG91, would do more to tame multipath. If you need lots of gain for the higher UHF channels, like 35-51, the XG91 should be a little better match. My 2 cents.

Steve

I have the 4228HD because of it's VHF capabilities. The Antennas Direct ClearStream 4 I had before caught none of my VHF stations. His TVFool report shows VHF stations.

goldrich

12-09-09, 07:58 PM

I have the 4228HD because of it's VHF capabilities. The Antennas Direct ClearStream 4 I had before caught none of my VHF stations. His TVFool report shows VHF stations.

Per the review at hdtvprimer......"I had High hopes for this antenna for VHF. I figured that with fewer vertical wires, it would not have the vertical currents of its predecessor. But the vertical rods it retains are enough to cause trouble.

The dip at channel 7 is caused by the antenna radiating greatly straight up and down, which diminishes its forward gain.

The dip at channel 9 is caused by the antenna radiating more out the back than out the front, which diminishes its forward gain."

http://www.hdtvprimer.com/ANTENNAS/TemporaryPage.html

According to Ken's VHF gain chart, the 4228HD's VHF capabilities on channels 7 and 9 are terrible, and basically the same as using rabbit ears. It appears that aero12 is expecting to receive WJLA on channel 7 and WUSA on channel 9. Personally, I'd prefer to read a little better review about an antenna for the channels I was wanting to receive. Of course, the suggested revisions could be conducted.

Anyone here had some personal experience using the 4228HD (without any revisions) for VHF channels, especially channels 7 and/or 9? My past reception tests with the old 4228 on channels 9 and 13 @ 36-38 miles over mostly flat terrain were bad.

Steve

klandry7

12-09-09, 08:33 PM

According to Ken's VHF gain chart, the 4228HD's VHF capabilities on channels 7 and 9 are terrible, and basically the same as using rabbit ears. It appears that aero12 is expecting to receive WJLA on channel 7 and WUSA on channel 9. Personally, I'd prefer to read a little better review about an antenna for the channels I was wanting to receive. Of course, the suggested revisions could be conducted.

Anyone here had some personal experience using the 4228HD (without any revisions) for VHF channels, especially channels 7 and/or 9? My past reception tests with the old 4228 on channels 9 and 13 @ 36-38 miles over mostly flat terrain were bad.

Steve

His 7 and 9 are only 3.5 miles away, so should be no problem even if it is no better than rabbit ears for those channels. Mine is unmodified and my 13 is my strongest station, I was looking at his WJZ 13 that is 36 miles away.

finlay648

12-09-09, 08:40 PM

Per the review at hdtvprimer......"I had High hopes for this antenna for VHF. I figured that with fewer vertical wires, it would not have the vertical currents of its predecessor. But the vertical rods it retains are enough to cause trouble.

The dip at channel 7 is caused by the antenna radiating greatly straight up and down, which diminishes its forward gain.

The dip at channel 9 is caused by the antenna radiating more out the back than out the front, which diminishes its forward gain."

http://www.hdtvprimer.com/ANTENNAS/TemporaryPage.html

According to Ken's VHF gain chart, the 4228HD's VHF capabilities on channels 7 and 9 are terrible, and basically the same as using rabbit ears. It appears that aero12 is expecting to receive WJLA on channel 7 and WUSA on channel 9. Personally, I'd prefer to read a little better review about an antenna for the channels I was wanting to receive. Of course, the suggested revisions could be conducted.

Anyone here had some personal experience using the 4228HD (without any revisions) for VHF channels, especially channels 7 and/or 9? My past reception tests with the old 4228 on channels 9 and 13 @ 36-38 miles over mostly flat terrain were bad.

Steve

My experience using the old 4228 from 75mi. was good for analog 7, 9, 11 and 13 but after the transition digital 9 and 11 had problems with adjacent channel interference so I had to add a YA1713.

aero12

12-09-09, 09:16 PM

My experience using the old 4228 from 75mi. was good for analog 7, 9, 11 and 13 but after the transition digital 9 and 11 had problems with adjacent channel interference so I had to add a YA1713.

with rabbit ears I am not getting 9

Digital Rules

12-09-09, 11:07 PM

guys. here is my TVfool (http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d7721f57b61e8b3)I'd like to do the best I can without trying 15 antennas! Any advice for this close but no line of sight situation?With all those buildings around, signal reflections will be a huge concern. A yagi style antenna like the Winegard HD7694P would be my personal choice. Unfortunately,there is no guarantee that any antenna will provide hiccup free reception under such conditions.

deltaguy

12-09-09, 11:35 PM

aero12,

What does the landscape to your south look like? If you could use your building to block reflections from the tall buildings nearby, you might be able to catch a good reflection from a southern aim, not in line with the "correct" aim. This would require a lower antenna elevation, however. It's a chance fix.

systems2000

12-10-09, 12:24 AM

2) another building at 340 to 30 degrees that rises to 100'
3) one at 30 to 60 degrees that rises to 120' (blocking line of site to Baltimore which are the second set of stations.)
4) and one at 130 to 180 degrees that rises to 200'

How far away are these buildings?
How important are WBAL & WJZ?

You'll find that there is no definitive answer to all antenna applications. Your situation is definitely going to have Multi-Path issues. WDCW and WNVC are your major stations not within 12° of each other for the D.C. Market. Since most of the D.C. stations are greater than 60NM, they should be fairly easy to catch.

Baltimore is going to be more of a challenge at 30-35° and levels of 6.5 to 17.4NM.

fatrhino

12-10-09, 11:46 AM

Looking for some advice here,
http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d7d5269350cd605

All of the main stations that I would like to recieve are 16 miles away from me, but signal levels of -50/-60dBm. There are also 2 VHF Hi channels in there. Unfortunately I am limited to an attic mounted antenna. I am looking at these:

CM2016
ANT751
CM2018

It would be just a single 25' RG6 run to 1 TV. Currently I can get all my main channels with a homemade UHF antenna, but it takes a lot of moving the antenna around the room to get an acceptable lock. Would any of those antennas listed be sufficient?

Larry Kenney

12-10-09, 03:23 PM

I've got two of the old CM 4228 antennas on my roof - one for the living room and one for the family room/bedroom TVs. Since the pros and cons of the 4228 are being discussed, I thought I'd pass on my experiences.

For UHF, the antenna works great. I can get UHF stations located 65 miles away on channels 21, 35 and 46 with no problem. But for VHF it does not work so well, and I've had to add an Antenna Craft Y-10-7-13.

We have two local VHF channels, one on 7 just 3/4 of a mile away and one on 12 five miles away. The 4228 works for those. Channel 7 is close enough that the 4228 brings in a strong signal... no problem. For channel 12 I get a fairly decent signal of 26 dB SNR, but nowhere near as good as the 32 dB I get with the VHF Y-10.

There are two VHF stations that are 65 miles away on channels 9 and 10. They are non-existent on the 4228, but 18 to 20 dB SNR on the VHF Y-10.

So, in conclusion, if you looking for reception of local VHF channels, the 4228 will work okay, but you'll need something else if you want to receive stations that are more distant.

Larry
SF

paris_tn

12-10-09, 07:16 PM

Has anyone checked lately if Lafayette Electronic Supply still has any Wade Delhi Vip-306's left or if Wade is still making them?

I know someone that is stacking some uhf's this weekend, that possibly might get a seperate vhf low and vhf high antenna as he is deep fringe but also thought about the vip-306. The problem is, he has both vhf high and low stations that are deep fringe. I bought a 306 6 or 8 months ago but is still in the box and haven't had a chance of putting it up. When i talked to Wade in Canada(8 months ago), someone mentioned possibly making the 307 again and keep on with the 306 as they were selling pretty good when i bought mine(or had picked up).

If Wade is not making the 306/307 anymore what would be the next best bet for a full vhf antenna or better yet would he just be better off getting a seperate Wineguard/Antennacraft for both vhf's? When i mention deep fringe, 65 to 100 miles but he is up high on a tower and on a good high elevated spot.

PCTools

12-10-09, 07:56 PM

FWIW, I bought two of those VIP307's, and they are monsters. In today's age, I see no purpose in trying to get these.

Just get a good Ch 7 -13 antenna, and you are fine. Unless, in your area you need to get channels below 7.

aero12

12-10-09, 08:08 PM

How far away are these buildings?
How important are WBAL & WJZ?

You'll find that there is no definitive answer to all antenna applications. Your situation is definitely going to have Multi-Path issues. WDCW and WNVC are your major stations not within 12° of each other for the D.C. Market. Since most of the D.C. stations are greater than 60NM, they should be fairly easy to catch.

Baltimore is going to be more of a challenge at 30-35° and levels of 6.5 to 17.4NM.

the building to the north (#2)is about 70 feet away. the building to the north east (#3) about 120' away. The building to the south (#4) is about 300' away. the building in line of sight with the main DC towers to the north west (#1) is about 120 away.

As another data point, I tried a cheap indoor/outdoor monoprice antenna today as I had a large order with monoprice last week and decided to give it a try. I discovered, or perhaps discovered, that the tuner on my Olevia 42" ($700 microcenter 2006 Olevia 542i) seems very substandard compared to a centronics zat 502hd tuner I have purchased for our second monitor type TV. I don't see any specific tuner problems on the 542i thread, but the centronics is getting twice as many channels and all better.

I have ordered today a Winegard HD-1080 from Amazon which was $35 shipped. I have read up a bit and realize they all have limits, but while I have full roof access and can do whatever I like up there, I have a flat roof with no masonry to use for attachment of antenna, so I a inclined to give a compact design of the 1080 a try first since I am going to mount it by drilling into some 4x4 under one of our larger air conditioning units. But it probably is unwise to go more than 10' up or to go with a larger antenna.

aero12

12-11-09, 08:48 PM

OK I have installed a Winegard HD-1080HD on my roof. It is about 8 feet up giving a net of a bit less than 50' above ground level. Alone it is doing better than the monoprice antenna (either in or outdoors) but not great. But I dug up a radioshack (http://www.radioshack.com/product/index.jsp?productId=2103092) "Bidirectional Cable TV Amplifier" and this greatly improves reception.

Also as I mentioned my Centronics Standalone tuner (which I bought for a tunerless monitor) does much MUCH better than the inherent tuner in my Olevia 542i. In fact I will be getting a second centronics to use with the Olelvia.

Here is my current set up: Winegard 1080HD 50' AGL, 50' coax, RS Bidir Amp" set at midpoint of output, "2 GHz four-way splitter", -> a) 6' to Olevia b) 120' to Centronics Tuner.

I don't know if the RS amp is optimum. It is four or five years old.

I am flabberghasted at the poor results from the internal Olevia tuner. Is there anything I should try before springing another $100 on a second centronics?

systems2000

12-11-09, 09:41 PM

Here is my current set up: Winegard 1080HD 50' AGL, 50' coax, RS Bidir Amp" set at midpoint of output, "2 GHz four-way splitter", -> a) 6' to Olevia b) 120' to Centronics Tuner.

I don't know if the RS amp is optimum. It is four or five years old.

Get yourself a Channel Master 3414 distribution amplifier and remove the Radio Shack Bi-Directional Distribution Amplifier and 4-way splitter.

I am flabberghasted at the poor results from the internal Olevia tuner.

That's because the Olevia tuner is probably a generation or two behind what the STB's currently have. I'm not sure if there are any televisions that currently have sixth generation tuners.

aero12

12-12-09, 07:13 AM

Get yourself a Channel Master 3414 distribution amplifier and remove the Radio Shack Bi-Directional Distribution Amplifier and 4-way splitter.....
That's because the Olevia tuner is probably a generation or two behind what the STB's currently have. I'm not sure if there are any televisions that currently have sixth generation tuners.

Thanks to you and everyone for the advice. I ordered a 3414 and will be buying a second centrionics ZAT

On the newer generation tuners I wonder how many people out there with three-year-old or older hdtvs are struggling with various antenna and other reception variables who would be better off giving a new $100 tuner a try!

Satcom15

12-12-09, 01:50 PM

Thanks to you and everyone for the advice. I ordered a 3414 and will be buying a second centrionics ZAT

On the newer generation tuners I wonder how many people out there with three-year-old or older hdtvs are struggling with various antenna and other reception variables who would be better off giving a new $100 tuner a try!

I'm curious aero, what was the model number of your Centronics tuner. Was that the Centronics ZAT 502HD? Also, I wonder if the current generation of TVs have better tuners in them. Perhaps the external tuner is still a smarter option.

Cheers

aero12

12-12-09, 04:51 PM

I'm curious aero, what was the model number of your Centronics tuner. Was that the Centronics ZAT 502HD? Also, I wonder if the current generation of TVs have better tuners in them. Perhaps the external tuner is still a smarter option.

Cheers

Mine is a Centronics ZAT 502 HD. I do not have the firmware/build version right in front of me now, but I ordered it about four days ago (it came in one day) direct from centronics site.

The comparison to the Olevia 542i tuner is profound. I receive many more channels and all digital channels better with the ZAt502HD. That includes placing the ZAT in the same place as the olevia and comparing with same antenna input using RS am, not using RS amp. using monoprice ant inside, using it outside, using roof winegard antenna.

I realized this is an antenna thread so I don't wish to distract, but it is an incredible difference at least with my Olevia. I had bought the centronics for an Olevia monitor only (Olevia 327) which although 120' further down the antenna run got much better than the integrated tuner Olevia

dvansowhat

12-12-09, 10:48 PM

There is a big difference in tv tuners as I have large lcd that will pick up more stations than my small lcd and I have a W-7698 feeding both. As far as tuners go I set up a 7698 antenna for my father and tried an RCA tuner on his old tv and received no signal so I set up my small lcd and it picked up all the stations that were avaible in his area which are 65 mi. away and this with no amp. So yes there is a big difference in built in tv tuners.

scottmo2020

12-14-09, 05:27 PM

Hi,
I posted this in the Grand Rapids forum a few days ago, but I wanted to see if any antenna experts here had some ideas.

http://www.avsforum.com/avs-vb/showthread.php?p=17708177#post17708177

I wasn't sure about cross posting and all of that type of stuff, but if anyone could check it out I'd appreciate it!
Scott

re_nelson

12-16-09, 11:12 PM

Situated in my attic some 40 miles north of the D/FW antenna farm, I'm very happy with the setup of a 91XG and YA-1713 combined into a CM-7777. Every single full-power signal from Cedar Hill shows a signal quality of at least 93% and even the 15 kW Us range from 72% to 87%.

So what's sub-optimal? Low band VHF. Although the programming on the market's low power facility on channel 3 is of no interest to me, I'd still like to see if I can get it better. Also given our proximity to Mexico, I'd like to try to pull in some of the analogs on 2-6 from across the border (atmospherics permitting, of course).

My plan is to grab an Antenna Craft Y5-2-6 and combine it with the hi-VHF YA-1713 using a Pico HLSJ and then feed that into the CM-7777.

Is that proposed scheme viable?

Tower Guy

12-17-09, 07:36 AM

My plan is to grab an Antenna Craft Y5-2-6 and combine it with the hi-VHF YA-1713 using a Pico HLSJ and then feed that into the CM-7777.

Is that proposed scheme viable?

The scheme is ideal.

re_nelson

12-23-09, 02:25 AM

As mentioned upthread, one part of my attic antenna setup is a Winegard YA-1713 which certainly lives up to its impressive reputation.

I'm curious about the design of this yagi -- particularly the parts on the rear boom -- comprised of 6 elements which I measured when the antenna arrived.

The rearmost is a 34.5" reflector and then there are two 24" directors on the front of that rear boom. So what of the remaining three middle elements? They measure 25.5", 19.5" and 34" from front to back, with the snapon cartridge under the 25.5" element. Are they three drivers strapped together tuned for different wavelengths or some other design?

rabbit73

12-23-09, 01:27 PM

The YA-1713 is a yagi/LPDA hybrid. A pure yagi would not have a wide enough bandwidth to cover 7-13. A Log-perodic (LPDA) design would cover 7-13, but the Y-1713 combines features of both (parasitic elements AND more than one driven element). The design is quite successful but you can see that it does best around CH11:
http://www.hdtvprimer.com/ANTENNAS/w1713.html
http://winegard.com/kbase/upload/ya-1713.pdf
http://www.hdtvprimer.com/ANTENNAS/comparing.html (http://www.hdtvprimer.com/ANTENNAS/comparing.html)scroll down to VHF and compare raw gain curves with net gain curves.

If you need only one VHF channel, then a single channel yagi would be better.
I've tried and tried to get KSFW from my location to no avail (in spite of being well within the contour as shown in the application). I have no problem at all getting low-V KHPK/3, with 300 watts...
www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d8adf75cb5f1056

Oh, yes. I see KSFW way down the list at -97.6 dBm 2Edge, far below KHPK/3.

holl_ands

12-24-09, 05:33 PM

The YA-1713 has two active elements in front of the rear, passive reflector.
They are interconnected with a crossover feedline, forming a two-element LPDA.
The other elements are directors, as in a typical Yagi design...forming a "Log-Yagi".

Log-Yagi's, like "similar" back half of an RCA ANT-751, are difficult to model in NEC2:
http://imageevent.com/holl_ands
Note that the gain loss across Ch13 predicted by NEC2 computer models was NOT
found when I (and others) did actual on-air tests....

The extremely close spacing of the director near the active elements
helps to adjust SWR, more than it affects overall gain.

Bruce Watson

12-26-09, 03:10 PM

Forgive me -- I've searched and searched and can't find a good answer to my question. But I can't believe it's not here -- it's got to be somewhere on the AVS forum site. So if anyone knows where I should be looking, please point me in the right direction.

My problem is multipath. I've got a CM 4220-HD (http://www.solidsignal.com/pview.asp?mc=03&p=CM4220&d=Channel-Master-CM-4220-TwoBay-HDTV--UHF-TV-Antenna-%28CM4220%29) on my roof. About 85 feet of coax (it's as short as I could make it). No amplifier -- AntennaWeb tells me that I'm about 13 miles from the major antenna farm that has most of the broadcast antennas for the stations I'm most interested in, so signal strength isn't my problem.

My problem is that eventhough I'm up reasonably high in the city I'd need at least 30 feet more height to clear all the buildings, and 70-100+ feed to clear all the trees to get clear line of sight to the antenna farm. Sadly, that's just not going to happen, so I find myself in multipath hell. You just gotta love an 8VSB signal. :rolleyes:

I'm thinking that what I need is an antenna with a tighter beam to cut down on the size of the side lobes, and thus cut down on the amplitude of the multipath signals. Said another way, to increase the strength of the main signal relative to the multipath parts. So I'm thinking along the lines of something like the Winegard HD-9032 (http://winegard.com/kbase/upload/HD-9032.pdf).

Am I barking up the correct tree here, or is there a better / easier / smarter way to approach the problem? If so, please enlighten me, because clearly I need it!

And if a corner reflector design (actually a Yagi design?) is in fact the right way to go, how do I find the right design for what I want -- which is a low gain but tight focus? Is that even made? And if not, are there any make-your-own designs out there for something like what I need?

Clearly I know just enough to be dangerous; any help really appreciated.

holl_ands

12-26-09, 03:31 PM

Seems you are headed in the right down the right "path".
Narrow beam antenna with a high Front/Back Ratio, such
as HD-9032, 91XG or CM-4228 (which also does Ch7-13).

You should ALSO insert a Variable RF Attenuator on the coax to
prevent overload desensitization:
http://www.solidsignal.com/pview.asp?mc=03&p=1296F&d=20dB-Variable-Attenuator-for-VHF-UHF-HD-OffAir-Reception-1296F&c=Signal%20Variators&sku=853748001293

You need to determine which direction the strongest, cleanest signal is
coming from....it might be a bounce off a building.

Older DTV receivers are particularly susceptible to multipath,
compared to DTV's built in the past two years...and any CECB.

rabbit73

12-26-09, 07:47 PM

Bruce Watson:

Your multipath problem reminds me of two previous posts by GSP and serendipity:
http://www.avsforum.com/avs-vb/showpost.php?p=15941020&postcount=1914
http://www.avsforum.com/avs-vb/showpost.php?p=15941531&postcount=1915

serendipity gives a link for a novel solution to a multipath problem:
http://www.prism.gatech.edu/~wn17/ note that it has two pages

systems2000

12-27-09, 12:15 AM

Seems you are headed in the right down the right "path". Narrow beam antenna with a high Front/Back Ratio, such
as HD-9032, 91XG or CM-4228 (which also does Ch7-13).
What about the Channel Master 4221HD?

It has twice the elements of the 4220HD, but half the elements of the 4228HD.

rabbit73

12-27-09, 12:23 AM

Vertical stacking of bowties narrows the vertical beamwidth, but it doesn't change the horizontal beamwidth. Multipath problems caused by buildings usually require a narrower horizontal beamwidth which is obtained by horizontal stacking.

The reason why the 4228 was so popular is because it gave a narrower horizontal beamwidth than the 4221, even though it didn't give anywhere near the promised theoretical gain increase of 3 dB.

bommai

12-28-09, 02:16 AM

I am building a house in Melbourne, Florida. I have a balcony in the back (facing west). I have pre-wired an RG6 cable into a box in the soffit of the balcony's roof. I was hoping to mount a smaller probably amplified antenna using a J-mount to the side of a 6"x6" pole that supports the roof of the balcony. The towers are 321 degrees and about 37 miles away. I need a directional antenna. Florida is pretty flat. I am new here so don't have experience with OTA reception. What is the best way to choose the antenna? I was hoping to avoid a big installation on top of my roof and just use a J-mount on the side of the pillar in the balcony.

Any advice?

The Hound

12-28-09, 03:29 AM

Only bump I see is NBC on channel 11, other wise a UHF yagi and you'd be golden.

holl_ands

12-28-09, 10:54 AM

Best way is to enter your location into www.tvfool.com to see how much "Noise Margin" (NM) is available...
then post the results URL here....

re_nelson

12-30-09, 01:10 AM

www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3d8adf75cb5f1056

Oh, yes. I see KSFW way down the list at -97.6 dBm 2Edge, far below KHPK/3.

You're looking at the (now gone) ultra-low power analog facility. The KSFW digital plant -- a scant 30.6 miles northward -- is LOS and -55.4 dBm, above that of KHPK/3. In theory, it ought to be 5x5 hereabouts.

I now have the AntennaCraft Y5-2-6 designed for low-band VHF which is ``not working'' as expected. But that a new topic downthread. :-)

re_nelson

12-30-09, 01:30 AM

The bright and shiny Y5-2-6 came in today but 't'aint working like I thought it would on low-band VHF. I'm convinced that I'm at fault in some way. Although it's a simple antenna, I must have somehow managed to botch things.

Now the story...and I'll go into excessive detail to make things clear:

I carefully unfolded all 5 elements, making sure not to bend or warp them.

Since its output impedance is a 300 ohm, I obtained a balun at Lowes. Why AntennaCraft doesn't provide one in a mostly 75 ohm age is beyond me. But...anyway...

I spread the balun's twinlead so that the spade lugs fit snugly into the terminal posts situated on the driver element and secured them with the supplied washers and wingnuts.

Then I hooked it up to a test set with an ATSC/NTSC tuner. Nothing. There's an analog on 6 that I get just fine with a little old Terk HDTVo. The big Y5-2-6 to the same set yields only snow. A usually reliable LD on 3 never captured on the digital side of the tuner.

Until...quite by accident, when re-aiming the Y5-2-6, I happened to touch the boom with the outer shield of the F-connector. Voila...there was analog 6 loud and clear.

I then put the newly-acquired Lowes Balun on another antenna (YA-1713) to see if the balun was faulty. That balun worked without fault when connected properly to the other antenna and without the outer shield touching the boom. But back on the Y5-2-6, no luck until I touch that shield to the boom.

Any ideas? It's two connections and a few sticks of metal. I'll be more than happy to fill in any gaps.

The Hound

12-30-09, 01:53 AM

Same lead, same TV for both antennas?

re_nelson

12-30-09, 02:43 AM

Same lead, same TV for both antennas?

Yep. Since my real world job involves troubleshooting, I know that isolating variables is critical in problem solving.

The black twin lead portion connecting to the Lowes balun was the same on both the Y5-2-6 and the YA-1713. In other words, I didn't modify the stock balun -- in spite of the fact that the ``spread'' is pretty wide on the terminals of the Y5-2-6.

When I connected the balun to the YA-1713, I used a couple of clip leads to connect to the wires where the Winegard cartridge housing would normally be. For the purpose of this A/B test, I did remove the supplied Winegard black cartridge part so that I could verify the correctness of the balun.

The RG-6 cable on the F-connector side of the balun was the same for both tests, a 12 foot length going directly to the television without any preamp, joiner, splitter or coupler.

One more oddity I since discovered. The low-band Y5-2-6 is pulling in nearly all of the high-band Vs and Us in the market when the balun is connected properly, that is without the outer shield touching the boom.

So, the Y5-2-6 is functioning as a pretty passable 7-51 antenna but not grabbing anything in the band for which it was designed. Sure is a lot of metal to function like a coat hanger! :-)

It's got to be something simple and braindead simple that I'm overlooking. Just to make sure I'm not fighting some balun madness, I'll grab another one later today. That's one variable that I can't test since I have only one at present.

Leave it to me to perhaps stumble upon a balun that has a notch filter below 174 mHz! :-) But it works when the F connector's metal shield touches the boom. Argh. Argv. Argc.

wildwillie6

12-30-09, 06:57 AM

ProjectSHO89

12-30-09, 08:18 AM

Simple question, I think: What TV channels do FM radio signals interfere with? (In an idle moment, I switched my "antenna" cable over to the antenna input of my FM receiver and got great FM reception . . . I had thought the FM trap had been enabled, but I guess it hadn't been. That led me to wonder what TV channels those signals might be interfering with.)

Willie,

FM-band broadcasts usually interfere with the high-VHF channels whose frequency is twice that of the FM broadcast's frequency.

The following chart is excerpted from Falcon_77's DTV spreadsheet.

High-VHF MHz FM Stations
ch freq range 2nd Order Harmonics
7 174 180 87 90
8 180 186 90 93
9 186 192 93 96
10 192 198 96 99
11 198 204 99 102
12 204 210 102 105
13 210 216 105 108

FM traps (passive filters) generally come in two varieties: Those that try to preserve channel 6 and those that don't.

If the filter tries to preserve channel 6, it won't start rolling off until around 89 mHz and will still let a lot of lower FM signal through until it hits its peak rejection somewhere closer to the middle of the FM band.

Those that don't try to protect channel 6 will start rolling of in channel 6's band and will pretty much whack the whole FM band by at least 25-30 dB, depending on design.

Tower Guy

12-30-09, 08:40 AM

Leave it to me to perhaps stumble upon a balun that has a notch filter below 174 mHz!

That's what I am thinking.

Tower Guy

12-30-09, 08:44 AM

systems2000

12-30-09, 10:22 AM

Are you using a pre-amp? Before the transition, I found that my FM trap (on my Channel Master pre-amp) needed fine tuning to get better reception on RF7. Luckily I found the problem before analog RF7 was off the air and it was easy to adjust.

If not adjusted right, a variable FM trap can destroy RF 6 or 7.

Attached, you'll find a table of the strong FM stations in my area and where the harmonics land within my VHF-High reception.

alphanguy

12-30-09, 12:06 PM

I have visited K7MEM's site where he has that UHF yagi design tool, and it works great... is there any plans or design tools online for a wideband DIY FM antenna?

re_nelson

12-30-09, 12:21 PM

Leave it to me to perhaps stumble upon a balun that has a notch filter below 174 mHz!

That's what I am thinking.

Tonight, I'm planning to pick up a couple of 300/75 ohm matching transformers, one from Lowes and the other from Radio Shack. That should allow me identify if the one from Lowes has an undocumented filter to reject anything lower than high-V.

I'll post a followup here with my findings.

holl_ands

12-30-09, 12:59 PM

I have visited K7MEM's site where he has that UHF yagi design tool, and it works great... is there any plans or design tools online for a wideband DIY FM antenna?
See K6STI's FM website (he also has an excellent medium-gain Yagi for Ch7-13):
http://www.ham-radio.com/k6sti/
K6STI's FM & Hi-VHF Yagis have very high Front/Back Ratios to suppress interference
from other channels & noise and are computer optimized to cover the entire band,
whereas most DIY Yagi's are only good across a much smaller bandwidth.

I analyzed several Hi-VHF antennas that can be rescaled for the FM band. They
include simple Folded Dipole, Loops, Yagis, Log Periodic Dipole Array (LPDA) and
Zig-Zag LPA with references to design information:
www.imageevent.com/hollands
Fortunately, Hi-VHF and FM bands both have bandwidths of about 21 percent.
For FM band, rescale all dimensions LARGER by a factor of TWO (196/98=2.0).

rabbit73

12-30-09, 09:27 PM

re_nelson

12-31-09, 02:54 AM

re_nelson:
Have you talked to Trip, I think he has a Y5-2-6:
http://www.avsforum.com/avs-vb/showpost.php?p=17603257&postcount=5345
http://images.townnews.com/southsidemessenger.com/content/articles/2008/12/18/news/top_stories/ts3.jpg

Thanks for asking. Yes, we briefly chatted in this forum several weeks ago. His home location has the AntennaCraft Y5-2-6 on the top with a Winegard PR-8800 below it as the links show. He noted that the Y5-2-6 is used for both high and low VHF. I didn't discuss the specifics of the balun or cabling, though.

But that does bring us to the followup I promised upthread:

I got out of work late tonight -- after all of the Radio Shacks were closed but Lowes was still open so I got a new and slightly different balun. The older I had from Lowes shows ``UHF/VHF MATCHING TRANSFORMER'' in white on black. The one I obtained tonight has a longer (4" vs 2.5") section of twin lead and has an embossed label of ``MATCHING TRANSFORMER''.

The newly-obtained balun now works fine in contrast to the older one which behaved almost as if it had a low-VHF notch filter. Odd that, eh?

Anyway, I'm rather surprised at how well this large antenna (80" boom and 110" reflector) performs on VHF high, which likely squares with Trip's experience. I guess there's just so much metal in the air that it's bound to capture most anything that looks like RF bouncing its way. :-)

The Y5-2-6 design is rather interesting to me and I'll defer to an expert to explain its traits. The driven element is a loop (folded dipole?), the bottom part of the loop is isolated from the boom (that's where the terminal posts are) but the top part appears to be electrically joined to the boom, along with the 3 directors and rear reflector. So smrat folks, how's this sucker work to pluck the pictures as they go flyin' through the air?

Tower Guy

12-31-09, 08:51 AM

The driven element is a loop (folded dipole?), the bottom part of the loop is isolated from the boom (that's where the terminal posts are) but the top part appears to be electrically joined to the boom, along with the 3 directors and rear reflector. So smrat folks, how's this sucker work to pluck the pictures as they go flyin' through the air?

The center of the folded dipole element has zero potential. It can be grounded without hurting the performance, and the ground is a great safety feature to prevent lightning from getting down the center of the coax.

rabbit73

12-31-09, 03:31 PM

re_nelson:
The newly-obtained balun now works fine in contrast to the older one which behaved almost as if it had a low-VHF notch filter. Odd that, eh?
Good detective work!

Thanks for letting us know where we might encounter defective baluns.

I tried about 20 different baluns to find the best one to optimize reception for CH15 with a CM4221. All of them worked, but the spread was over 5 dB so the extra effort was worth it.

holl_ands

01-01-10, 11:07 AM

FYI: In addition to the antenna combiner comparison test, tballister also
tried various modifications to the DB-8, including a wire to connect
the ends of the whiskers, feedline vs splitter and an angled reflector
extension. The much larger reflector was the most effective:
http://www.antennahacks.com/Hacks/MyDB8.htm
He also did some OTA antenna comparisons using a spectrum analyzer:
http://www.antennahacks.com

keeper

01-03-10, 04:40 PM

Hey guys- I have a question. I am trying to get a channel 11 and 13 from about 58 miles away at very good elevation. I started with the Y5-7-13 antenna craft but am getting some dropouts eventhough strength on my dish meter is at around 93. Thinking of getting the Y10-7-13. I am thinking that I have some multipath problems because the signal will drop down to 70ish for a few seconds before returning to 90+. Anyway how much of an improvement is the Y10 over the Y5. And is the Y10 more directional? Thanks

Tower Guy

01-03-10, 05:36 PM

Anyway how much of an improvement is the Y10 over the Y5. And is the Y10 more directional? Thanks

2.5 db

http://www.antennacraft.net/Yagi.html

11 degrees sharper.

keeper

01-03-10, 05:44 PM

tHANKS

PCTools

01-03-10, 06:17 PM

AntAltMike

01-03-10, 09:51 PM

I bought a white noise generator with a 5-2,000Mhz output and -10dBmV output level for about $300 that is the size of a cigarette pack. I think it was made by Applied Instruments. ...

Applied Instruments has cut its price for its NS-1 white noise generator, which I had actually paid more like $380 for a few years ago, to $199 plus about $8 shipping.

You can now order it directly from them HERE (http://www.appliedin.com/www/products/NS-1.html).

When you tune some notch filters, the tuning can change if it has a removable box or lid....and of course you should use a non-metalic tuning wand. ...

...A funny thing about tuning Winegard UT-2700s is that even though the adjustable tuning component is a capacitor, which is non-inductive, it is in the proximity of inductive circuitry, so an inductive tuning tool will throw off the tuning value just by being near some other component when adjusting those variable capacitors. These appear to be the same variable capacitors that I have no trouble tuning in MX-4U 4-channel combiners (discontinued a decade ago, but I have a stash that I won't share with anyone at any price!) using the smaller of the two, Radio Shack, anti-static blade-type tuner adjustment tools, but when I remove the tool from the UT-2700s, the notch moves, so I first see what the maximum benefit is that I can get with the tool installed, then I misadjust it a little to the left and right until, upon removal of the tool, the notch jumps back to where it had been optimal with the tool inserted in the capacitor's slot.

The slot on those tunable capacitors is really slim, and I haven't yet found a non-inductive tuning blade. If anyone can recommend one, I'll buy it and give it a shot.

Wiha 27013 Precision ceramic, 1.3 mm non-magnetic, antistatic, slotted screwdrivers, which are absolutely ideal for tuning the Winegard UT-2700 dual tunable notch filter, can be found for $13 each or less by Googling, "Wiha" and "27013". Like lots of small purchases, the shipping is brutal on a quantity of one, so wherever you buy it, you might as well poke around and see if they have anything else you might need.

300ohm

01-04-10, 01:28 PM

but Lowes was still open so I got a new and slightly different balun. The older I had from Lowes shows ``UHF/VHF MATCHING TRANSFORMER'' in white on black. The one I obtained tonight has a longer (4" vs 2.5") section of twin lead and has an embossed label of ``MATCHING TRANSFORMER''.

The newly-obtained balun now works fine in contrast to the older one which behaved almost as if it had a low-VHF notch filter. Odd that, eh?
The outdoor ones Lowes now sells are Phillips also available at Wal-Mart.
From what Ive observed from other posters, they can be very good or not so good, it depends on the individual unit/batch. Luckily, the two I have seem to be very good. :)

craftech

01-08-10, 10:23 AM

Did you produce a solution and, if so, how did it come out?

I decided to wait until spring. The pitch on her roof is almost as steep as a Swiss Chalet and I am 64 years old. Not a good combination for Winter roof installations.

I'll update this at that time. Thanks again.

John

holl_ands

01-10-10, 11:19 AM

Just purchased a new Denon AVR-3310, which has HD Radio. Looks like I will be buying an outdoor FM antenna. No more room left on the top of the tower with the Funke High Bander, and a stacked array of 91XG's.

Unless:

1) Their is some forgiveness with Funke HighBander's, as to my knowledge they only receive Ch. 7 - 11, whern FM is between Ch. 6 - 7.
2) I will have to crawl back up on the tower and disable the FM trap feature on the Channel Master Pre-Amp.

Any thoughts?
FM is roughly 88-108 MHz, whereas Ch7 starts at 174 MHz...not even close....
But any chunk of metal is going to pickup "something"....go ahead and try it...
Do you really "need" a rotatable FM antenna???? If not, mount it lower on the mast....

You might also have success with one of the better Indoor (or Outdoor) DIY antennas:
http://www.avsforum.com/avs-vb/showthread.php?p=17814917

Ennui

01-10-10, 12:56 PM

Yesterday, I installed my new YA1713 below my HD9095P. Works very well for LA stations:

Now have NBC-4 4.1,2,4; KABC 7.1,2,3; KCAL 9.1; KTTV 11.1; KCOP 13.1. Had KCBS 2.1 and KTLA 5 before, of course.

I am in West San Marcos at 615 feet ASL.

The HD9095P had a connection for a VHF antenna built into the feed box. Made it very easy to use the existing feedline and preamp AP8275.

You will note I modified the mounting so the reflector end would not hang over the edge of the roof. We have lots of birds that like high places

scottmo2020

01-10-10, 03:44 PM

I have a similar situation to above where I am trying to get VHF 8 and VHF 12 from about 58 miles. Most of the time I get at least 90% signal on my meter but frequent dropouts. It is the Wineguard VHF 7-13 antenna with Wineguard AP8700 preamp. Currently it is mounted on a 5 foot pole on top of an old dish mount with the garage roof behind it. I am thinking about moving it and hopefully get a better quality signal.

First, I am thinking about mounting it under my CM4228, but will I be too close to either the CM antenna or the roof? My other option is to move it up to the peak of the roof on a tripod. You can see the garage roof sligtly lower where I am thinking of mounting the tripod, but I'd rather not if I can get away with putting it under the CM. Pics are attached.

Thanks!
Scott

Ennui

01-10-10, 05:19 PM

workingmantom

01-10-10, 11:27 PM

ngarrang

01-11-10, 09:43 AM

I don't use a rotor. I have two antennas running into a combiner and get all but one station from everything available in Dayton and Cincinnati. I am smack in the middle of the two markets. A DB8 pointing south, a DB4 pointing north.

Ennui

01-11-10, 10:14 AM

I need some help choosing an antenna. I would like to receive ABC which I haven't received OTA for 4 years. I currently use two CM4221's, one pointed between 123* and 155* magnetic to receive CBS, FOX and NBC. The other is pointed at 334* to receive KICU, although KICU shows up as an analog channel.
I saw a Winegard HD7697P on sale and was wondering if this would be sufficient for my needs. I do not want to use a rotor, is this antenna able to receive a signal from the back to eliminate the first 4221?

I do not think you will get a useable signal off the back of the 7697. You will see the front-back rating is pretty high.

If you can, I would add a VHF antenna to what you have to get ABC.

The one I installed was about $50 from Solid Signal.

paris_tn

01-11-10, 07:33 PM

Keeper, Lafayette, Electronics has a channel 11 antenna that is 10 element cut for ch 11. I think the cost is around 36.00. Here are the specs on it. They only have 1 left and maybe about 3 left for channel 10.

10y11s

http://www.wade-antenna.com/Wade/cutchannel.pdf

Hey guys- I have a question. I am trying to get a channel 11 and 13 from about 58 miles away at very good elevation. I started with the Y5-7-13 antenna craft but am getting some dropouts eventhough strength on my dish meter is at around 93. Thinking of getting the Y10-7-13. I am thinking that I have some multipath problems because the signal will drop down to 70ish for a few seconds before returning to 90+. Anyway how much of an improvement is the Y10 over the Y5. And is the Y10 more directional? Thanks

paris_tn

01-11-10, 07:36 PM

An expensive uhf antenna called Fracarro 6HD. This thing needs to flat perform for that price.

http://www.skyvision.com/store/mi1500209.html

Tower Guy

01-11-10, 07:58 PM

I need some help choosing an antenna. I would like to receive ABC which I haven't received OTA for 4 years.

Your ABC is KGO on channel 7 with a noise margin of -10.8 db. Theoretically, to receive it you would need an antenna with 14 db gain and a preamp with a noise figure of 3 db. 14 db gain would take a stack of 4 VHF high band off-the-shelf antennas.

But, don't go out and build such an antenna without very careful design. Your NBC is on channel 8 and 67.8 db stronger. You could reduce that to about 30 db using high F/B ratio antennas and stagger stacking. If you also did a critical horizontal space of 80" and aimed the antennas to minimize the interference you'd have a 50/50 chance of success when the weather conditions are favorable.

I'd get a used Dish network receiver and subscribe to All American Direct. You'd get KGO for a monthly fee of $3.99 per month.

https://www.mydistantnetworks.com/faq.php

Ennui

01-11-10, 08:35 PM

Your ABC is KGO on channel 7 with a noise margin of -10.8 db. Theoretically, to receive it you would need an antenna with 14 db gain and a preamp with a noise figure of 3 db. 14 db gain would take a stack of 4 VHF high band off-the-shelf antennas.

But, don't go out and build such an antenna without very careful design. Your NBC is on channel 8 and 67.8 db stronger. You could reduce that to about 30 db using high F/B ratio antennas and stagger stacking. If you also did a critical horizontal space of 80" and aimed the antennas to minimize the interference you'd have a 50/50 chance of success when the weather conditions are favorable.

I'd get a used Dish network receiver and subscribe to All American Direct. You'd get KGO for a monthly fee of $3.99 per month.

https://www.mydistantnetworks.com/faq.php

The Winegard 1713 has a 9.1 dBd (dipole reference) rating or 11.3 dbi (isotropic) for Channel 7 and a F-B rating of 10.5 db. The chances of reception should be good with a low noise preamp for the coax run even if there is a strong signal 10 MHz away off the back. If it is a problem, a High Q trap could be introduced. Do you agree?

workingmantom

01-12-10, 09:15 AM

Thanks for the feedback, I'll have to do a little more research on the subject. Tom

Tower Guy

01-12-10, 09:53 AM

The Winegard 1713 has a 9.1 dBd (dipole reference) rating or 11.3 dbi (isotropic) for Channel 7 and a F-B rating of 10.5 db. The chances of reception should be good with a low noise preamp for the coax run even if there is a strong signal 10 MHz away off the back. If it is a problem, a High Q trap could be introduced. Do you agree?

A high Q trap won't help. You'd need a channel 7 bandpass filter or a channel 8 elimination filter.

The old high Q traps worked OK for analog because a majority of the power was centered around the visual carrier. A DTV signal is a full 5.5 mhz wide. A high Q trap doesn't remove enough of the DTV signal.

The next problem is the loss of the filter adds to the noise figure. To get back to 3 db of system noise figure, you'd have to use a GASFET preamp with a noise figure of about 1 db.

A single YA1713 doesn't have enough gain. The antenna gain minus the noise figure of the preamp added to the NM must add to a number higher than zero.

Ennui

01-12-10, 11:18 AM

A high Q trap won't help. You'd need a channel 7 bandpass filter or a channel 8 elimination filter.

The old high Q traps worked OK for analog because a majority of the power was centered around the visual carrier. A DTV signal is a full 5.5 mhz wide. A high Q trap doesn't remove enough of the DTV signal.

The next problem is the loss of the filter adds to the noise figure. To get back to 3 db of system noise figure, you'd have to use a GASFET preamp with a noise figure of about 1 db.

A single YA1713 doesn't have enough gain. The antenna gain minus the noise figure of the preamp added to the NM must add to a number higher than zero.

A second YA1713 perfectly matched to the first would only add 3db of signal at the expense of increased sharpness of orientation. In my experience, it is difficult to get the 3 db.

arxaw

01-12-10, 11:23 AM

...First, I am thinking about mounting it under my CM4228, but will I be too close to either the CM antenna or the roof?...The roof shouldn't affect it, unless you have foil-backed radiant barrier roof decking (http://www.lpcorp.com/techshield/) (visible from the attic, on the underside of the roof decking).

Ennui

01-12-10, 01:29 PM

Thanks for the feedback, I'll have to do a little more research on the subject. Tom

I note on the TVfool data, you have a height agl of 20 feet. Why don't you try 40 feet to see what effect that might have on the ABC strength.

paris_tn

01-16-10, 11:45 PM

A friend is going to try a 12 footer and extended more than my 91xgs. He is going to stack two of these horizontal and try them out. Two 6 ft boom sections. The boom is joined in the middle. The antenna has 32 directors and the boom is built on square 3/4 by 3/4 aluminum.

http://webpages.charter.net/rscarbro/Superxg.jpg

http://webpages.charter.net/rscarbro/Superxg3.jpg

http://webpages.charter.net/rscarbro/Superxg5.jpg

Untill the weather gets warmer, i am trying extensions on mine and then will try a 4 stack when the weather warms up.

http://webpages.charter.net/rscarbro/91stackextend.jpg

http://webpages.charter.net/rscarbro/91stackextend1.jpg

Rando01

01-19-10, 10:24 AM

Now thats an antenna........

ngarrang

01-19-10, 10:52 AM

Wow! So...what the theoretical gain on that monster?

BCF68

01-19-10, 12:20 PM

BCF68

01-19-10, 12:21 PM

Wow! So...what the theoretical gain on that monster?

About 17.5 dBd

holl_ands

01-19-10, 03:40 PM

Only when the narrow beamwidth is actually smack on target.
Any sort of wind is gonna whip it back and forth....until it bends/breaks....
Anyone care to model how much gain is lost in that saggy boom....
and how much more is lost as the boom is bend sideways by the wind....

Bruce Watson

01-19-10, 05:16 PM

I've been looking all over for a wall plate to use to run my rotor control cable through the outside wall of my TV room. Need to get that cable up to the roof and the antenna rotor somehow, yes? So at some point it has to breach the wall and come in the house. There are thousands of plates to use for coax, telephone, etc. But I don't find anything specifically for rotor wire.

It would be nice to find a connector / wall plate designed just for this. Anyone have any pointers? Else, I'm thinking that using an RJ-11 connector should work just fine. I'm a little worried that it can't handle the power however. Anyone have any opinions, thoughts, suggestions?

Edit: Ah, yes, almost forgot. Four or more conductors.

paris_tn

01-19-10, 08:17 PM

He made 3 more for a 4 stack going up soon. His has no sag. Very strong and only two boom sections. In the picture you can see a little sag in his because he did not tighten up the two booms together. He held them up for a picture and did not even tighten things up on the two booms. They was in two pieces.

As far as gain on his 12 footer, not sure and who knows if it will be as good as a stock 91xg or extended. I think an extended 91xg is just over 10 ft. The entended 91xg's with 4 boom sections has more sag than his 12 footer, with 2 6ft sections. He has a 100ft tower they are going up on. BCF68, the good info over at antenna hacks mentions maybe 1.5db gain on the extended 91xg and test comming soon. I think i have read in here where some liked the extensions and some did not and could not tell any difference. So it will be interesting to see when antenna hacks does test to see if it is any helpful or not.

I try to keep an open mind on if they are better or not. I am running a 4 way combiner and only two antennas, so i figure i have a lil more loss than i should. I plan to put two more up for a 4 stack as it gets warmer but to get up over the trees i am deciding to get another tower and go on up 80 ft to get over the trees. The trees do not bother me as bad going north and up to Cape Mo, so i do better up that way. The day my extensions was put on Cape(Kbsi) and Harrisburg, IL(Wsil) was comming in very strong during the day. They are both right at 125 miles from me, from my house to the towers. Full scale in the afternoon. Most of the time during the day they will not come in. The next two nights(weekend), Cincinnati, OH, Ft Wayne, IN, Indianapolis, Dayton, Louisville, Lexington, Ky was flat pegging me all night long. I have about 35 or 40 stations that came in and most lasted 3 or 4 hours. It was skip.

I had been noticing late at night and early in the morn, where Louisville, KY and about 3 or 4 stations up there was ususlly in. The one i want to watch i think is called Wave 3 and it comes in the worse. The one on ch 41 seems to beat them all. That is just over 250 miles but is this just a fluke? Maybe it is and i want to give them a long test because with this rain moved in i am getting the same stations i always did and not going anymore than 75 miles. In bad weather. I want to get to a normal day and see. I have a friend in Murray & Mayfield and one of them picks up a station in St Louis and i have only done that once as where he watches St Louis on his 91xg's often. I think once i got Kmov but other morning i did watch Ksdk awhile.

BCF68, my goal was try to reach out 100 to 125 miles at night(and hold fade down) on a regular night and hold the station. This gives me EVille(118 miles), Nash(85 miles) area and up in Cape and Harrisburg does good. Going south, i am right in the trees. Most of the time i can not even get pbs station in Lex, TN 45 miles from me. I have not checked since the extensions was put on. If anything and it is way to early to pass judgement on my extensions but i seems the longer antennas are holding better and less fade but i have had everything comming in or not much at all with weather extremes. Other night i was picking up some Cookville station and some station with xx on the end and said Crossville, Knoxville.

It is possible i might take mine down soon, while i am having my 4 stack, stacking bar being made and if i do, the friend might stick one of his 12 footers or a 2 stack of his 12 footers to see how they work for a week or so. I will say this, it is amazing to pick up Louisville and wonder, why no Lexington, Ky comming in and only Louisville? Then turn the antennas just a little and then you see Lexington pop in. holl_ands is right on with the narrow beam width and 4 should be even more so.

BCF, i am about limited to Jackson going south and it booms in but i want to get up over the trees and try south. I hardly turn down that way as my north and even east does so much better.

systems2000

01-19-10, 08:20 PM

Bruce Watson,

An old telephone plug will do the job.

arxaw

01-19-10, 09:31 PM

Search for 4-prong phone plugs and 4-prong phone jacks on eBay.

http://i50.tinypic.com/2pphj0k.jpg

http://i46.tinypic.com/akizpx.jpg

Tschmidt

01-20-10, 12:16 AM

I'm thinking that using an RJ-11 connector should work just fine.
I'd stay away from using a modular plug for two reason: current capacity and familiarity. Someone seeing it will "assume" it is a phone connector.

The idea of using an old style 4-prong phone plug is interesting. When I built our house (predivestiture) used circular plastic AMP connectors for speaker and rotor wiring disconnects.

http://www.tycoelectronics.com/catalog/feat/en/c/10574?BML=10576,16358,17560,17685,17686

arxaw

01-20-10, 07:00 AM

Using 4-prong phone jack/plugs, there shouldn't be much chance of plugging the wrong thing into the jack. They're becoming harder to find and I suspect many younger people don't even know what they are for.

If 4-prong jacks/plugs are used, I would consider buying a couple of spares, in case one is needed in the future for a repair.

systems2000

01-20-10, 04:49 PM

Using 4-prong phone jack/plugs, there shouldn't be much chance of plugging the wrong thing into the jack. They're becoming harder to find and I suspect many younger people don't even know what they are for.
I guess I'm showing my knowledge or age (or both). :D

holl_ands

01-21-10, 12:06 AM

Different types of wall plates. "HDTV/HD15" takes a DE-15P plug:
http://www.parts-express.com/wall-plates.cfm?CFID=22177066&CFTOKEN=55387053
http://www.cablestogo.com/product_list.asp?cat_id=2234
http://www.amazon.com/s/ref=nb_ss?url=search-alias%3Daps&field-keywords=hd15+wall+plate&x=0&y=0

Just don't mistakenly plug a VGA monitor cable into it....

systems2000

01-21-10, 09:21 AM

Those are much more complex to wire up and not as likely to be as reliable. The telephone style is straight four wire and have screw or clip style terminals for the wires.

Ennui

01-21-10, 11:43 AM

I use a straight "feed-thru" tube I got somewhere many years ago. That way, I do not have to worry about bad splices.

Bruce Watson

01-21-10, 11:45 AM

Search for 4-prong phone plugs and 4-prong phone jacks on eBay.

Excellent. I snagged one of these wall plates locally. Seems perfect for the application. Thanks for the suggestion!

While I'm at it, any reason to not use dumb old phone wire (solid conductor) for the rotor control wire? I was leaning toward stranded wire when it occurred to me that this wire wasn't going to be moving much. It runs to the rotor motor, and that end doesn't rotate.

Also, what about grounding? The RG-6 quad-shield coax from the antenna itself is grounded to a nearby water line, and the antenna is above the rotor obviously. But... do I need to ground the rotor wire also? If so, what's the "accepted" way to do this?

Ennui

01-21-10, 11:54 AM

I am not sure how big your rotator motor is but phone wire won't carrry much current. I would use a proper 4 wire rotor lead. On mine, one of the wires is ground so I do not ground separately. I do have my antenna feed run through a ground coupling with a 4 foot copper ground rod into the ground.

FYI. YMMV

AntAltMike

01-21-10, 12:25 PM

Also, what about grounding? The RG-6 quad-shield coax from the antenna itself is grounded to a nearby water line, and the antenna is above the rotor obviously. But... do I need to ground the rotor wire also? If so, what's the "accepted" way to do this?

Once upon a time, the NEC required that antenna rotor wire be flat and that the outer two conductors had to be grounded. Thus, it had one more conductor than the circuitry required to operate the rotor. That requirement was eliminated long ago.

The antenna mast has to be grounded with 8 gauge aluminum, 10 gauge copper or 17 gauge copper clad steel wire, connected to the ground electrode system. Connecting it to a cold water pipe is technically in violation of the NEC, but lots of people do it anyway. Prohibition of the use of a cold water pipe for that purpose began with the 2002 code revision, but the reason for it was that since so many repairs were being done with plastic pipe, future repairs risked breaking the antenna mast's ground path. If it's your own house and all you care about is the safety factor introduced by grounding the mast, then you might as well ground it to a cold water pipe if that is most convenient to you.

300ohm

01-21-10, 12:59 PM

I am not sure how big your rotator motor is but phone wire won't carrry much current.
Yeah, typical rotor wire is 20 gauge and solid copper telephone wire is 24 gauge. Plus its not UV resistant. Another option is low voltage outdoor 18 gauge wire sold at Lowes or Home Depot. IIRC it comes in 2, 4, 5 and 6 conductors.

arxaw

01-21-10, 04:45 PM

Ennui

01-21-10, 05:12 PM

This separate ground rod should be bonded to the house electrical main ground, to prevent ground loop voltages.

The house electrical is 100 feet away. On all my antennas in the past, I have never hooked to that ground. Where does the ground loop voltage come from?

systems2000

01-21-10, 06:05 PM

Bruce Watson

01-21-10, 06:25 PM

Once upon a time, the NEC required that antenna rotor wire be flat and that the outer two conductors had to be grounded. Thus, it had one more conductor than the circuitry required to operate the rotor. That requirement was eliminated long ago.

The antenna mast has to be grounded with 8 gauge aluminum, 10 gauge copper or 17 gauge copper clad steel wire, connected to the ground electrode system. Connecting it to a cold water pipe is technically in violation of the NEC, but lots of people do it anyway. Prohibiition of the use of a cold water pipe for that purpose began with the 2002 code revision, but the reason for it was that since so many repairs were being done with plastic pipe, future repairs risked breaking the antenna mast's ground path. If it's your own house and all you care about is the safety factor introduced by grounding the mast, then you might as well ground it to a cold water pipe if that is most convenient to you.

Oh, interesting. Turns out I put the interior walls in myself in this area of the house. This particular water spigot feeds directly from the main water line coming into the house (it's like two feet away at this corner of the house). It's all copper from the spigot out to the street. But mainly I'm just piggy-backing on the existing wiring (and the grounding to the water spigot) that Time Warner did when I used to have cable. :D

Interesting too that code wants a copper or aluminum wire of pretty thick gauge, or a much thinner copper clad steel wire. Why would the steel wire be thinner? The only reason I can think is that it might act like a fuse and melt through when struck, and the steel would provide continuity should the copper (which will carry nearly all the power on the surface, yes? Because it's high voltage) melt. Or it's something entirely different?

Anyway, where does one find a suitable wire to use for antenna grounding? And do you attach to the antenna itself, or to the mast (on the antenna side of the rotor I'm guessing)?

This is more complicated than it looks. But if it's worth doing, it's worth doing right.

Bruce Watson

01-21-10, 06:36 PM

Yeah, typical rotor wire is 20 gauge and solid copper telephone wire is 24 gauge. Plus its not UV resistant. Another option is low voltage outdoor 18 gauge wire sold at Lowes or Home Depot. IIRC it comes in 2, 4, 5 and 6 conductors.

Interesting. The wire that I used to use when this rotor was last in service (25 years ago?) was "real" rotor wire (at least that's what the guy who sold it to me at a ham-fest told me :rolleyes: ). It worked fine for many years. I'd reuse it but it's really stiff and the insulation is cracking. But the conductors look to be closer to 26 gauge. Very small. Which is why I figured that phone cable should be fine.

But since I'm thinking of looking for a newer rotor, maybe I should go with a thicker rotor wire. I just couldn't find any that was 4 conductor in a convenient length (I don't want 1000 feet)... Hmm.... (sound of scratching head).

Ennui

01-21-10, 06:43 PM

From the ground potential difference carried across the coax shield.
http://en.wikipedia.org/wiki/Ground_loop_(electricity)

In your case, you need ground blocks at both ends of the 100' coax.

Cold water pipe grounding is only an option for those who are connected to a water distribution system and must be continuous metal pipe from the grounding point to the main water entrance.

When I said 100 feet, I meant from the point of my ground rod to the electrical box. From my ground rod, the RG6 goes up 45 feet to the preamp at the antenna and through the wall 4 feet to my TiVo.

AntAltMike

01-21-10, 08:56 PM

The mast ground wire can be stranded or solid, and uninsulated or insulated. You can get 10 gauge copper stranded by the foot at any home supply store. You are almost always better off using copper instead of aluminum because aluminum may react with whatever you ground it to.

The 17 gauge steel is acceptable because it is more survivable. Its job is to bleed off static electricity. No ground wire will withstand a direct lightning hit, but some will be adequate to shunt away the current from 110 or 220 line voltage that might come in contact with the coax.

The code says that it is the mast, not the antenna, that has to be grounded. It also says that the downleads must be grounded with insulated copper wire approximately equal in current carrying capacity to the outer conductor itself. Last I knew, cable TV companies commonly used 12 gauge solid, insulated copper wire for that purpose. I use 10 gauge solid insulated copper, but for some reason, home supply stores never stock that product. If you want it, you'll probably have to get it from an electrical supply house, but realistically, you'll likely only need a few feet of it as long as you pick a penetration point that is near a suitable ground.

Not that anyone but the mattress tag police will care, but any supplementary ground rod used in conjunction with the mast grounding has to be 8 feet long and 1/2" in diameter.

300ohm's recommendation of 18 gauge low voltage wire seems like a practical solution for the rotor controller. You can probably find the old fashioned "real", flat rotor wire in 50 and 100 foot lengths.

AntAltMike

01-21-10, 09:10 PM

From Summit Source: 75' 3 conductor flat rotor wire: $5.89
http://www.summitsource.com/philips-sdw142217-3-conductor-cable-antenna-rotator-75-ft-flat-automatic-rotor-wire-outdoor-aerial-signal-finder-locator-connector-controller-part-sdw1422-p-8188.html

I think all flat rotor wire is 20 gauge.

systems2000

01-21-10, 10:44 PM

When I said 100 feet, I meant from the point of my ground rod to the electrical box. From my ground rod, the RG6 goes up 45 feet to the preamp at the antenna and through the wall 4 feet to my TiVo.
OK. I was thinking you had a free standing tower that was 100' from the house.

systems2000

01-21-10, 10:59 PM

Bruce WatsonAnyway, where does one find a suitable wire to use for antenna grounding? And do you attach to the antenna itself, or to the mast (on the antenna side of the rotor I'm guessing)?I use aluminum lugs, with self-tapping hex head screws, for all my tower and satellite pole installations.

http://www.skywalker.com/itemdisplay.aspx?item=226211

Don't forget to not exceed an 8" bend radius on the ground wire.

arxaw

01-22-10, 07:11 AM

... Last I knew, cable TV companies commonly used 12 gauge solid, insulated copper wire for that purpose. In our area, that's what coxcable uses. AT&T uses #10 gauge solid copper insulated wire for their grounds here.

Ennui

01-22-10, 01:03 PM

OK. I was thinking you had a free standing tower that was 100' from the house.

Thanks. This is my antenna system.

Rando01

01-22-10, 05:26 PM

Thats a nice setup..

300ohm

01-22-10, 09:12 PM

300ohm's recommendation of 18 gauge low voltage wire seems like a practical solution for the rotor controller. You can probably find the old fashioned "real", flat rotor wire in 50 and 100 foot lengths.
Finding the 5 conductor stuff locally for my old Alliance rotor seems to be practically impossible, so thats why I looked for alternatives. Actually, I think that outdoor 18 gauge stuff is used for wiring up automatic lawn sprinkler systems.

Ennui

01-23-10, 11:55 AM

Thats a nice setup..

Thanks. It is a Winegard HD9095P UHF on top of a modified mount Winegard 1713 High VHF. I have a Winegard AP8275 preamp. The HD9095P has an input connector for a VHF antenna so adding the 1713 was easy as I did not have to change or move the amp connections.

The rotor is a Yaesu 450XL that is overkill for this but it was twisting a 3 element full size 20 meter beam earlier at this location.

pkx

01-23-10, 07:48 PM

Pardon the cross-post, a also posted this in the SF Bay Area OTA thread. I'll include some more information here for those not familiar with the area.

I'm hoping others can help me choose an antenna.

I'm moving into a 2nd story townhouse in Milpitas where the living room's windows face south and east. I have a porch outside the south facing window. Most of the channels are broadcast from Sutro Tower in San Francisco, 37 miles from me, in the northwest direction.

I bought a small Winegard SS-3000 inside powered antenna and pointed it toward Sutro (which would be at the wall which has another townhouse on the other side of it). Reception was poor (quality level 50ish for most channels, couldn't get ABC (7.1) it *all*).

I could probably get away with mounting an outdoor antenna on the patio (the Channel Master 4228 perhaps?), but would that be much good since facing toward Sutro would be pointing it "back through the townhouse" building? Maybe it'd be OK because it'd pick up reflections off of the mountains?

Getting into the attic would be a bit of a challenge, drilling a hole in the ceiling (no easy way to get it through the walls in this construction) for coax...

I'm also not against using an outdoor antenna in the corner of the room mounted to the wall. It'd be big and ugly, maybe I could come up with a way to "decorate" it? Paint it to match the wall?

I'd love to hear others' thoughts. Thanks!

Ennui

01-23-10, 08:25 PM

pkx

01-23-10, 08:41 PM

I understand you do not have access to the attic from your unit? You should plot your stations from TVfool.com to determine frequency, strength and direction for the channels you want. Paste a link here.

I do have access to the attic, but the way it's configured and the number of beams that cross it... It takes me about 15 minutes to contort my body enough to navigate through 10 feet :)... and I'm a pretty small guy. The attic is only about 4' tall at the center.

Here's my TVFool link.
I'm most interested in receiving
Virt:
5.1(CBS)
4.1
2.1 (FOX)
11.1 (NBC)
7.1 (This is ABC that I can't seem to pick up - looks like it's high VHF)

Any others are just a bonus.

http://www.tvfool.com/modeling/tmp/c723/d44/1f63dfc/Radar-All.png

Ennui

01-23-10, 09:02 PM

Both 7.1 and 11.1 would require an antenna that picks up high VHF. The others are UHF. The stations are all quite strong at your location.

I would really try to get a small UHF/VHF antenna up in the attic. Then you would have a clear shot assuming your roof is not metallic. You do not need a big one since the stations are strong.

pkx

01-23-10, 09:04 PM

I would really try to get a small UHF/VHF antenna up in the attic. Then you would have a clear shot. You do not need a big one since the stations are strong.

Yeah, I was disappointed by the performance of the indoor amplified Winegard I picked up relative to what tvfool says I should need. Do you have a VHF/UHF recommendation? If I put it up in the attic, small vs large doesn't matter so much, so if there's not a huge cost difference.. The 4228HD won't do well on ch7, huh... that's a bummer because it seems like a good price for the reception.

Edit: This Channel Master 2018 seems to be a good deal - I'd have to see if I can actually fit something that long in the attic.

Ennui

01-23-10, 09:08 PM

Yeah, I was disappointed by the performance of the indoor amplified Winegard I picked up relative to what tvfool says I should need. Do you have a VHF/UHF recommendation? If I put it up in the attic, small vs large doesn't matter so much, so if there's not a huge cost difference.. The 4228HD won't do well on ch7, huh... that's a bummer because it seems like a good price for the reception.

I would try the Winegard HD7000R because it will lay flat on the joists and I do not think you need more if you go to the attic. (You might want to raise it off the joists if there are heating ducts or wires below.)

pkx

01-23-10, 09:18 PM

I would try the Winegard HD7000R because it will lay flat on the joists and I do not think you need more if you go to the attic. (You might want to raise it off the joists if there are heating ducts or wires below.)

Excellent - thank you for all of your help!

Ennui

01-23-10, 09:20 PM

Amazon has it for $36.

arxaw

01-24-10, 07:16 AM

The Winegard HD7000 has very long elements for VHF lowband. None of your channels are on VHF low, so it would be a lot of wasted width you don't need and possibly difficult to put in your attic.

I believe this much smaller VHF highband + UHF antenna (http://www.solidsignal.com/pview.asp?mc=03&p=ANT751) would be a better choice for your channels of interest.
http://pimages.solidsignal.com/ANT751.jpg (http://www.solidsignal.com/pview.asp?mc=03&p=ANT751)

Just place it on top of a cardboard box to get it up off the attic floor and aim at Sutro Tower.

Tower Guy

01-24-10, 01:27 PM

I believe this much smaller VHF highband + UHF antenna (http://www.solidsignal.com/pview.asp?mc=03&p=ANT751) would be a better choice for your channels of interest.
http://pimages.solidsignal.com/ANT751.jpg (http://www.solidsignal.com/pview.asp?mc=03&p=ANT751)

I agree with arxaw.

gadgetfreaky

01-24-10, 04:32 PM

I currently have a silver sensor antenna that I hooked up outside, 25ft up, but i'm getting some days where NBC, Fox break up and get digitized. Signal strength is about 30-35%. I wanted to replace the antenna and make sure I don't have issues. TV fool says this
http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dc7230ffcf3eed0
http://i48.tinypic.com/2eofber.jpg

I need a UHF/VHF antenna I suppose. It would be mounted outside, on the lip of the roof. Since it's so high up, i'll have to hire someone to install so I want to make sure the antenna I buy is definitely going to work. It's connected btw to Directv OTA receier. I just don't like he compression of DirecTV, hence wanting to now get OTA digital HDTV.

Suggestions? will this RCA work as suggested above? http://www.amazon.com/RCA-ANT751-Outdoor-Optimized-Reception/dp/B0024R4B5C/ref=sr_1_1?ie=UTF8&s=electronics&qid=1264369164&sr=8-1

arxaw

01-24-10, 04:48 PM

Suggestions? will this RCA work as suggested above? http://www.amazon.com/RCA-ANT751-Outdoor-Optimized-Reception/dp/B0024R4B5C/ref=sr_1_1?ie=UTF8&s=electronics&qid=1264369164&sr=8-1Yes. That's a good price, too.

You have both VHF & UHF, which the above antenna should receive well, per your TVFool.

dt_

01-24-10, 08:18 PM

systems2000

01-24-10, 09:07 PM

You'll need a VHF-Hi/UHF antenna and I'd try to point it between 207° and 210° to acquire stations between 203° and 220°. You have fairly strong levels and should be able to use most any quality antenna, although I would have chosen one like this. http://www.solidsignal.com/pview.asp?mc=03&p=OBO-HD-1080&d=OPEN-BOX-ITEM--Winegard-HD1080-2Bay-Bowtie-UHF-and-High-Band-VHF-TV-Antenna-(HD1080)&c=TV%20Antennas&sku=

Tower Guy

01-24-10, 09:18 PM

I'm new to the whole over-the-air DTV thing and I'm having some trouble picking up signals that TVFool says I shouldn't really have an issue with. I recently got a USB TV Tuner for my laptop and am now using a Monoprice antenna I just purchased

The Monoprice antenna has an internal amplifier. The signal strengths on tvfool are so strong that your problem may be the amplifier.

Plain old rabbit ears will work better, or you may consider the Terk HDTVi.

deltaguy

01-24-10, 09:22 PM

dt_,

A laptop can emit substantial interference. If your antenna is anywhere near it, it may be killing signal. This is typically worse on VHF, but UHF is subject as well. Getting the antenna away from the laptop might be a solution. The more distance the merrier.

dt_

01-24-10, 10:34 PM

The Monoprice antenna has an internal amplifier. The signal strengths on tvfool are so strong that your problem may be the amplifier.

Plain old rabbit ears will work better, or you may consider the Terk HDTVi.

Are you suggesting that the amplifier is actually causing problems, or that something is actually *wrong* with the amplifier?

@deltaguy: Are you sure? I'll experiment with distances and see what happens. Right now the antenna is maybe 3 feet away from the laptop.. is that long enough? I'll move it farther away and report on any improvements. Thanks for the tip.:)
edit: Well, moving the laptop farther away from the antenna didn't really cause any significant improvements except I was able to get ABC for about 3 seconds, during which it was all pixelated, and then I lost the signal. I haven't been able to reclaim it since. :/

deltaguy

01-24-10, 11:10 PM

dt_,

I've personally seen a new Dell laptop dump signals at upwards of 10 feet away. 3 feet is certainly not enough. That particular laptop is more detrimental to signal than a conventional computer tower. Much much worse. The fact that KGO appeared, makes this even more likely to be the cause of your problem. Your TVFool shows plenty of signal, so don't be afraid of adding lots of coax to gain your antenna some distance.

dt_

01-24-10, 11:57 PM

deltaguy

01-25-10, 12:51 AM

arxaw

01-25-10, 07:58 AM

^ Interesting. I do actually have a Dell XPS laptop :P Would it help to disable radios like wi-fi and bluetooth? Are these the main source of interference? If not, what in particular is emitting the interference? My desk is next to the window so unless I really have to, I'd like to be able to watch tv on the desk. Could the fact that the walls around here are mostly solid concrete have anything to do with it? A lot of my neighbors have trouble getting cell phone signal, for instance.

I will think about getting a longer coax cable too, however. :)
Concrete walls can really degrade reception, especially KGO ABC & KNTV NBC, which are in the VHF band. VHF doesn't penetrate walls as well as UHF. VHF is more prone to interference from all sorts of electronic devices like your computer, etc. An amp will only amplify the noise.

If you have a radio shack nearby, try model 15-1874 (http://www.radioshack.com/product/index.jsp?productId=2103077) un-amplified rabbit ear/loop antenna (If it doesn't work, return it for a refund).

Buy an extra 10'-12' length of RG6 coax cable and add it to the antenna, using a barrel splice (http://i25.tinypic.com/2pq5bpe.jpg), also available at RS.

Extend the dipole rods no longer than 14"-15" each (to optimize for the frequencies KGO & KNTV are using) in a "V" shape like this (http://i29.tinypic.com/15pl4zk.jpg), and place near a window facing SouthWest.

Make sure any electronic devices like computers, blue tooth, routers, wireless/cordless phones in the room are far away from the antenna. Try opening the window, to see if it affects reception. Insulating low-e glass can degrade reception too, particularly VHF.

If some channels are weak, try moving the antenna up/down, left/right, until you find a hot spot. A foot or two change in location can do wonders, just like moving around with a cell phone to get out of a dead reception spot.

If none of this helps, post back here.

(generally, if a cell phone doesn't work well in a building, TV reception is not going to work well, either).

aethyrmaster

01-25-10, 11:07 AM

It's been a LONG while since my last post here, but it's time again...

The SBGH antenna that I've been using has been good, but it's time to go for a REAL antenna now - my wife "just wants stuff to work, without playing or tweaking or building."

So, I'm after an outdoor antenna.

http://farm5.static.flickr.com/4070/4303326229_727cd6a6fd_o.jpg

I/my wife care about 6 stations, anything more is a bonus.

Station|Real Channel|Virtual Channel|Call Sign

NBC|11|28.1|WBRE
CBS|13|22.1|WYOU
ION|32|64.1|WQPX
PBS|41|44.1|WVIA
FOX|45|56.1|WOLF
ABC|50|16.1|WNEP

1. I have a metal roof.
2. I have Aluminum siding.
3. As you can see, I need VHF-Hi as well as far out into UHF territory.

I don't mind mounting to the side of the house; I just don't know the best way to mount through it and stay waterproof. I'd rather not mount ON the roof.

I do have a front porch. I *can* mount to that, but I'd lose height. Having that information, here are the questions I have:

1. Would a single 7-69 antenna be better or worse than a good UHF and good VHF with a combiner?

2. How do I mount through aluminum siding while staying waterproof?

3. If I mount a pipe to the side of my porch, how tall can I go above the last mounting bracket before wind load can be an issue? I realize this is dependent on type of antenna; is there some general amount that's bad? 2 feet, 5 feet? 10 seems like total overkill, and I wouldn't go that far.

4. Repeat question #3, but with a roof tripod mount?

arxaw

01-25-10, 11:58 AM

1. I have a metal roof.
2. I have Aluminum siding.
3. As you can see, I need VHF-Hi as well as far out into UHF territory.

I don't mind mounting to the side of the house; I just don't know the best way to mount through it and stay waterproof. I'd rather not mount ON the roof.

I do have a front porch. I *can* mount to that, but I'd lose height. Having that information, here are the questions I have:

1. Would a single 7-69 antenna be better or worse than a good UHF and good VHF with a combiner?

2. How do I mount through aluminum siding while staying waterproof?

3. If I mount a pipe to the side of my porch, how tall can I go above the last mounting bracket before wind load can be an issue? I realize this is dependent on type of antenna; is there some general amount that's bad? 2 feet, 5 feet? 10 seems like total overkill, and I wouldn't go that far.

4. Repeat question #3, but with a roof tripod mount?Your virtual & real columns are reversed.

1. This antenna (http://www.amazon.com/RCA-ANT751-Outdoor-Optimized-Reception/dp/B0024R4B5C/ref=sr_1_8) should work fine.
Or this one (http://www.solidsignal.com/pview.asp?mc=03&p=HBU22).
Or this one (http://www.solidsignal.com/pview.asp?mc=03&p=HD7694P).

2. Use silicone sealant under mounting bracket & screws.

3. If your TVFool is correct, you don't need much height. Wind load shouldn't be much of a problem with a smaller antenna.

4. If you have a gable end of a roof peak that faces East or NorthEast, that would be the ideal location for your antenna.
A long J-mount (http://www.solidsignal.com/pview.asp?p=DS3000), installed on the gable end at the roof peak should work well for these smaller antennas.

Links are for example. Items may be available locally.

PCTools

01-25-10, 12:18 PM

Why did you mount the bottom antenna off-set like that?

Thanks. This is my antenna system.

dt_

01-25-10, 12:22 PM

If you have a radio shack nearby, try model 15-1874 (http://www.radioshack.com/product/index.jsp?productId=2103077) un-amplified rabbit ear/loop antenna (If it doesn't work, return it for a refund).

Extend the dipole rods no longer than 14"-15" each (to optimize for the frequencies KGO & KNTV are using) in a "V" shape like this (http://i29.tinypic.com/15pl4zk.jpg), and place near a window facing SouthWest.

Thanks for all the advice! :) I actually don't have a window facing southwest however unless I go in a different room that's not where I'd prefer to watch TV.. is it still likely that the dipole antenna you recommended would work from a room on the north side of the building (despite the concrete walls on the south side :/ ) ?

Furthermore, is there a reason why that unamplified antenna would be more likely to pick up the VHF signals than the amplified Monoprice antenna I got?

Ennui

01-25-10, 12:58 PM

Why did you mount the bottom antenna off-set like that?

Because we have a lot of birds that like high places and when the antenna is pointed North (most of the time), the antenna does not hang over our nice white wood patio cover. That is why I went with the HD9095P also.

I have had many antennas on that rotor and shaft: 20 meter 3 element and (later) a 10 meter 5 element beam. I had a UHF/VHF Winegard above both to get LA PBS stations. We had a real bird problem. When I sold all my ham gear, I also sold the ham antennas. I then took down the long UHF/VHF antenna and put up the HD9095P. Just last month, I put up the YA1713 VHF.

holl_ands

01-25-10, 02:17 PM

hello!

I'm new to the whole over-the-air DTV thing and I'm having some trouble picking up signals that TVFool says I shouldn't really have an issue with.
I recently got a USB TV Tuner for my laptop and am now using a Monoprice antenna I just purchased (this one (http://www.monoprice.com/products/product.asp?c_id=109&cp_id=10901&cs_id=1090101&p_id=4728&seq=1&format=2), specifically) to get TV signals. However, I am not able to get any VHF channels (ABC 7.1 and NBC 11.1 aren't picked up at all and don't get recognized in Windows Media Center) and some of my UHF channels (namely, 5.1 CBS / KPIX-DT) are getting pixelated / stuttering audio. Of course, some channels like 2.1 (Fox), 4.1 (MyNetwork) are fine.

I live in the third floor of an apartment building that has some concrete walls, but the antenna is near the window. It seems that even when I point the antenna in the southwest direction (and upward, of course), signal is not really improved. I certainly do not get ABC or NBC which is quite important to me.

Should I return this antenna and get a different one? I'd like an indoor antenna that can get both the UHF and VHF bands and that won't break the bank.

My TV fool results can be seen here: http://www.tvfool.com/?option=com_wrapper&Itemid=29&q=id%3dc7231ef86864b2

Thank you very much! Any help would be much appreciated :)

dt_
That Monoprice only has ONE "Ear"....you need TWO "Ears" for Hi-VHF.
With only one "Ear", it's acting as a monopole antenna, with only a very
minimal "ground plane" when trying to receive horizontally polarized
signals ("Ear" sideways). And when the "Ear" is vertical, it only receives
signals from those few stations using both vertical and horizontal polarization.
With TWO "Ears" it can operate as a proper tuned dipole....with higher gain.

The internal 20 dB gain amplifier is probably "overloaded" by your strong signals,
generating intermodulation noise products across many of the weaker channels:
http://www.odyseus.nildram.co.uk/Systems_And_Devices_Files/Linearity.pdf
You should NOT be using either an amplified antenna or a Preamp.
First try a simple, returnable, non-amplified Loop/Rabbit-Ear antenna...

Computers (and most other electronic devices that contain a "processor")
generate RF signals, which can "leak" into the VHF and UHF TV bands.
The FCC has set some limits on how much leakage is "acceptable", but
the closer you are the more of a problem it can be....and FCC approvals
are for the first (tweaked) prototype unit and not guaranteed in production.

You can TEST to see whether your laptop is a problem or not. Wrap aluminum
foil COMPLETELY around a cardboard box and (briefly) put the laptop inside it...
Be sure the foil overlaps so no RF energy (OR HEAT!!!) escapes. Also warp foil
around the power cord for a couple feet and a set of Earbuds/Headphones.
Since you can't watch the laptop inside, LISTEN for audio dropouts via the
earbuds/headphones. Don't let the laptop sit inside the hot box very long!!!