> I just just sat one antenna on top of the other, piggyback
> style, with the top antenna extending about 10 inches in
> front of the bottom one. So they are touching, attached
> together with duct tape and zip ties.... lined up vertically
> and horizontally, just staggered front to back with about a
> 10 inch offset.

Sounds like a vertical version of the "two antenna trick":

http://www.hdtvprimer.com/ANTENNAS/ganging.html#TAT

Although being so close, they are surely modifying each other's
reception pattern. If it works be happy.

Thanks for that tid bit Konrad.

I definately don't have any forward null.... this setup has increased my signal by about 15 percent over my single XG-91, while the vertical and horizontal stacks I did (according to everyone's instructions) didn't do a damn thing, except a 48 inch horizontal gave me about 5 percent improvement. And someone asked about hi-VHF... my lone high VHF is digital chanel 7, and it's coming in steady at 75 percent signal strength with this setup... no LOS, and 40 miles out. All my other channels are much mroe stable, and just for kicks, I switched over to see if there was improvement on analog as well, and my weakest station, which is 78 miles out, (channel 17) was crystal clear last night, when it ususally is snowy. I'm just saying the horizontal stack didn't impress me, but the piggyback sure does!

After thinking about it, I guess thye aren't lined up vertically. When I attatched the top one to the bottom one, I rested the bottom of the "U" bracket, and the bottom of the reflector grid on the boom of the lower one. The BACK of the reflector grid on the top unit is touching the FRONT of the reflector grid on the bottom unit. So this makes the top antenna point at a downward angle compared to the bottom one. Techincally, it's not supposed to work, but it damn well does!!!

I was referring to a forward null resulting with the traditional configuration. There's really no telling what's happening now. If it works for you though...:)

If you ever go back "traditional" you might try swapping the polarity on one of the baluns to check your phase.

And someone asked about hi-VHF... my lone high VHF is digital chanel 7, and it's coming in steady at 75 percent signal strength with this setup... no LOS, and 40 miles out.
Heh, I was half kidding about that, but had a hunch it may do well in that configuration for vhf-hi.

Can someone explain to me the effects of daytime vs nightime on television reception in UHF and VHF?

Thanks.

Can someone explain to me the effects of daytime vs nightime on television reception in UHF and VHF?

Thanks.

Usually, the temperature inversion will make reception better at dawn and the early evening hours. Afternoons are usually the worst for reception.

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

Also look here under Fading : http://www.hdtvprimer.com/ANTENNAS/GlossaryA.html#fading

Thanks again 300ohm.

Here is my performance rankings list based on my observations on the indoor antenna thread so far.

Updated

Channel Master 4220 with CM 7777 amp on roof
DB2 with Channel Master 7777 amp on roof
RS 1880
RS DA-5200
RS 15-1892 UFO
Channel Master 4220 unamped indoors
DB2 unamped indoors
Winegard SS-3000
RCA ANT1500
Classic Single Bow Tie
My First Attempt at the Coat Hanger Antenna, Youtube Video Specifications unamped
Terk HDTVa
Philips Silver Sensor
Philips MANT 510
Philips MANT940
Channel Master 4030
RCA ANT108 (very similar to the RCA ANT110 and the Philips MANT110 and others)
RS 1868 Delta
RCA ANT1020
Terk TV-5
Terk TV-1 without Loop
RS FM Dipole

Jensen TV-931
RS 1870

Where is a good place to buy a side arm attachment for a Rohn Tower? I want to add some more antennas on the side of it.

Any ideas?

IIRC, you paid a pretty penny for that other fairly plain bar you purchased. You can probably buy the metal pipe and ends needed and have those little local welding shops, found in the yellow pages, weld one together for you for a decent savings. But use steel and paint it, aluminum and the cost to weld it is high. And lightweight strong steel tube from about 1 1/4 inches to 3 inches OD, bent just the way you want it, is available from any good muffler shop with bending jigs. Just my 2 cents.

One big benefit of doing it custom, is that you get exactly the mount you want.

Where is a good place to buy a side arm attachment for a Rohn Tower? I want to add some more antennas on the side of it.

Any ideas?
http://w9iix.com/

I bought my gin pole from this guy. Good stuff.

Ron

Folks,

Some time ago I asked for some advice regarding my location. The CM 4221 was suggested, and some thought it might pull in the hi-VHF (channel 10) ABC broadcast.

I had been using the amplified "omnidirectional" radio shack "pizza" antenna, which gave me acceptable reception on my UHF channels, and unacceptable reception of ABC. The CM 4221 has pegged my receiver (a Dish VIP722) on 100% signal for the UHF channels, but has no signal lock on ABC at all, no matter what direction I point it in.

I'm guessing that a pre-amp is not going to help (my coax run is probably 75-100 feet), but I base that on the signal being so strong for the UHF signals --- am I right about that?

The 4221 was a cheap experiment; does anyone have a new suggestion? I've about given up on pulling in channel 4, since it will move to UHF in February. Unfortunately, I'll have 2 hi-VHF channels to deal with at that point, so I'd like to solve this problem.

Anyone got any experience with this new "ClearStream2" antenna from Antennas Direct? It claims hi-VHF reception, but no one seems to know anything about it.

> The CM 4221 has pegged my receiver (a Dish VIP722) on 100% signal
> for the UHF channels, but has no signal lock on ABC at all, no
> matter what direction I point it in.

The CM 4221 is a UHF antenna. For VHF-HI stations you want a
VHF-HI antenna. Try a YA-1713 or Y10-7-13.

http://www.hdtvprimer.com/ANTENNAS/w1713.html

> I've about given up on pulling in channel 4, since it will move to
> UHF in February.

I have the YA-1713. The current 3 analog VHF-HI stations are
beautiful. VHF-LO analogs have some ghosting (not bad considering
it's not supposed to be a VHF-LO antenna), but digital channel 4
comes in surprisingly well.

Folks,

Some time ago I asked for some advice regarding my location. The CM 4221 was suggested, and some thought it might pull in the hi-VHF (channel 10) ABC broadcast.

I had been using the amplified "omnidirectional" radio shack "pizza" antenna, which gave me acceptable reception on my UHF channels, and unacceptable reception of ABC. The CM 4221 has pegged my receiver (a Dish VIP722) on 100% signal for the UHF channels, but has no signal lock on ABC at all, no matter what direction I point it in.

I'm guessing that a pre-amp is not going to help (my coax run is probably 75-100 feet), but I base that on the signal being so strong for the UHF signals --- am I right about that?

The 4221 was a cheap experiment; does anyone have a new suggestion? I've about given up on pulling in channel 4, since it will move to UHF in February. Unfortunately, I'll have 2 hi-VHF channels to deal with at that point, so I'd like to solve this problem.

Anyone got any experience with this new "ClearStream2" antenna from Antennas Direct? It claims hi-VHF reception, but no one seems to know anything about it.

Check out the Winegard HD-1080 or Channel Master 2016 for compact UHF/VHF solutions. The HD-1080 can be found for $35 plus shipping online. I am using one at 14 miles with LOS. I suspect the CM 2016 may have stronger VHF performance though.

> The CM 4221 has pegged my receiver (a Dish VIP722) on 100% signal
> for the UHF channels, but has no signal lock on ABC at all, no
> matter what direction I point it in.

The CM 4221 is a UHF antenna.
I get that, but several regulars here chimed in last time, saying it could often receive VHF-HI.

For VHF-HI stations you want a
VHF-HI antenna. Try a YA-1713 or Y10-7-13.

http://www.hdtvprimer.com/ANTENNAS/w1713.html

> I've about given up on pulling in channel 4, since it will move to
> UHF in February.

I have the YA-1713. The current 3 analog VHF-HI stations are
beautiful. VHF-LO analogs have some ghosting (not bad considering
it's not supposed to be a VHF-LO antenna), but digital channel 4
comes in surprisingly well.

Thanks for the suggestion.

Ken

I get that, but several regulars here chimed in last time, saying that a 4221 could often receive VHF-HI.


Bad advice.

While a 4221 has some reception ability on VHF-Hi, the directivity is poor and therefore the multipath is high.

Those who have found that a 4221 works on High band V are in areas where the signal is extremely strong that there is nothing nearby to cause reflections.

Bad advice.

While a 4221 has some reception ability on VHF-Hi, the directivity is poor and therefore the multipath is high.

Those who have found that a 4221 works on High band V are in areas where the signal is extremely strong that there is nothing nearby to cause reflections.

OK, lesson learned.

How directional are the HD-1080 and the CM-2016? I have towers separated by close to 90 degrees.

Ken

OK, lesson learned.

How directional are the HD-1080 and the CM-2016? I have towers separated by close to 90 degrees.

Ken
They are both advertised as medium-directional, so I'm not sure how that would play for you, but if you split the difference, it may do the trick.

Id go withthe HD 1080, it should have a better beamwidth than the yagi on UHF.

Folks,

Some time ago I asked for some advice regarding my location. The CM 4221 was suggested, and some thought it might pull in the hi-VHF (channel 10) ABC broadcast.


I'm guessing that a pre-amp is not going to help (my coax run is probably 75-100 feet), but I base that on the signal being so strong for the UHF signals --- am I right about that?

The 4221 was a cheap experiment; does anyone have a new suggestion? I've about given up on pulling in channel 4, since it will move to UHF in February. Unfortunately, I'll have 2 hi-VHF channels to deal with at that point, so I'd like to solve this problem.



The reflector on the cm4221 is too small for VHF-hi, if you can, add some metal rods or screen to make the reflector about 32" wide or wider and you will see an improvement.

I've had success with this set-up in a number of locations picking up channels 7,8,11 & 13 @ 35mi plus.

This will by no means make the cm4221 a great VHF-HI antenna but should pull in stations about 40 mi. away under normal conditions if the antenna is out in the open and at a reasonable height.

This will do nothing for VHF-lo

After trying a handful of indoor antennas (including the Radio Shack UFO and Terk Indoor Amplified), I have decided to go with an outdoor antenna setup. I'm a super newb and not sure which mount type is best. Should I mount it on the roof, and if on the roof should I saw a chimney mount bracket? Or should it go straight into the ground or on the side of the house? Anyways, I priced a setup at Radio Shack a week ago and it came out to about $150 (not including the coax cable). And then today I found the Web site solidsignal.com and they seem to have really good prices. I'm curious to hear how the outdoor antennas have performed for you in your area. I'm in an area where there is good amount of tall pine and other assorted trees. I don't want to get something that's going to be overkill for my needs, but certainly something that can give me solid/dependable signal. I've included the printout for my house from TV Fool. TIA for any input :)

http://img.photobucket.com/albums/v294/Hank3/TV.jpg

Hank3,

Check out http://www.hdtvprimer.com/

Lots of good info.

I just installed a Winegard 7084. I am pleased with it's performance. But, the majority of the stations that I am trying to pull in are 40 to 50 miles. Your TVFool profile shows a much greater variation in distance.

The new antenna is attached to the chimney, because that is where my old antenna was installed. However, I believe most experts, for safety's sake, would recommend using a tower.

As you get in to this, you will discover, as I have, that digital OTA reception is not "apples to apples" with analog reception. Would I still invest in the antenna? Yes. But, I won't be sure I made the right decision until after the digital transition takes place next February.

Tommy

Thanks for the response, Tommy. What do you mean by a tower setup - do you have any pics? I'm not sure I follow you on the "apples to apples" explanation of digital and analog reception with regards to the switchover in February.

Thanks for the response, Tommy. What do you mean by a tower setup - do you have any pics? I'm not sure I follow you on the "apples to apples" explanation of digital and analog reception with regards to the switchover in February.

Hank,
By tower, I mean "into the ground".

Many digital broadcasts are not yet at full power. Also, many stations are not broadcasting on their final channel and will be changing in February. Receiving digital broadcasts, in my experience is more finicky than analog. With digital, you get pixelation which means your picture "freezes up".

Also, you must have a digital tuner. Depending if you are feeding an HDTV set or an analog set, you will need the appropriate built-in tuner or set-top box.

Tommy

OK - I think I gotcha now :) I'm trying to get the outdoor antenna setup so that I can get my DirecTV AM21 tuner to work.

Are there downsides to having the the antenna on a tower? I thought having the antenna on a roof was better since it's higher up?

DX'ers,

Thinking about adding two additional 91XG's in a 2 X 2 box configuration. That is, I would mount 2 directly below the existing antennas. Thus, 2 horizontally stacked, and then 2 vertically directly below them.

Attached is a picture of my set-up.

What are your thoughts, besides I loose the Funke VHF antenna and forcing me into buying a better rotor?

Thanks!

Chad

Are there downsides to having the the antenna on a tower? I thought having the antenna on a roof was better since it's higher up?

Heh, the towers being discussed are much higher than your roof. The downside is the large cost.

Chimney mounts are OK, as long as you keep the mast length to around 5 feet and the antenna to about 5 lbs max. In your case, with signals stronger than -70dbm, that shouldnt be a problem. You're not trying to get stations weaker than -105dbm, are you ?

In your case, a rotor would also be nice.

Solidsignal and Summitsource are good places to buy from online. I would avoid RS, the mall prices are way too high for inferior products.

Thanks, n4yqt. I'm wondering if I should hire someone at this point to install it.

What are your thoughts, besides I loose the Funke VHF antenna and forcing me into buying a better rotor?

Ganging 2 more antennas to a 2 gang set is probably only going to get you small marginal results.

I would think a tilt rotor would get you more DXing for the buck.

300 Ohm,

I tested the tilt rotors in the past and did not feel they were worth the high dollar value for what they did. Also, there is ONLY one place to purchase these from and they spank you on cost.

Ganging 2 more antennas to a 2 gang set is probably only going to get you small marginal results.

I would think a tilt rotor would get you more DXing for the buck.

PCTools-

Don't all four antennas have to be manufactured precisely the same for ganging to work its best? I seem to remember something a while back about someone getting a second antenna of some model and finding that its design or build had subtle differences in it from the antenna that he already had on hand. So it makes me wonder if the new antennas that you'd buy now would be perfect matches for the two you already have.

Hank: If you decide to go with a professional, make sure they are licensed and insured, too. MATV installers would be the best to find since they install commercial TV antenna systems for multi-users
(ie" condo, apartment, business, etc.)

Super!!! Thanks fot the tip :)

DX'ers,

Thinking about adding two additional 91XG's in a 2 X 2 box configuration. That is, I would mount 2 directly below the existing antennas. Thus, 2 horizontally stacked, and then 2 vertically directly below them.

Attached is a picture of my set-up.

What are your thoughts, besides I loose the Funke VHF antenna and forcing me into buying a better rotor?

Thanks!

Chad

You'd be better off with a horizontal quad, then you could keep your Funke. I've tried them both, horizontal works best IMO.

Both the dual and quad stack will have some hi vhf gain "through the back" just FYI. If you have a decently strong hi vhf you'll probably still pick it up using the 7777 in combined uhf/vhf mode. I pick up a vhf 12 digital from 55 miles with my current setup.

The 9521 would still probably do it since it's inside the tower and protected by the bearing. My 9521 is still hanging in there.

You'll need the 4-way stripline combiner for the best result. A 4 way splitter in reverse won't work. Believe me, I've tried it. Using 3 two-way splitters does work, but not as well as the 4 way stripline will.

PCTools-

Don't all four antennas have to be manufactured precisely the same for ganging to work its best? I seem to remember something a while back about someone getting a second antenna of some model and finding that its design or build had subtle differences in it from the antenna that he already had on hand. So it makes me wonder if the new antennas that you'd buy now would be perfect matches for the two you already have.

It was probably me you remember. I picked up two more DAT 75's and they were a different design than the earlier one (with larger reflectors and a different pcb balun). I eventually figured out how to phase them through trial and error. The "new" DATs require 5.5 inches less coax per antenna. I think the "extra length" is added pcb trace inside the balun.

Below are snapshots from RADIO MOBILE Propagation Prediction Program.

Sutro Towers is the futuristic triple tower structure on top of hill in central S.F.
NBC (CH12) comes from a nearby hill SE of Daly City with only a very small
(negligible) difference in angle of arrival.





OK So I have a rooftop installed with a pre-amp and I get everything I need EXCEPT channel 11.1 (NBC) It comes in only sometimes and quickly fades out. I am using a combo antenna and it works fine, except NBC. It is VHF only about 4 degrees off the main towers.

Should I get a higher grade main antenna or just get a VHF only for channel 11 and combine it to my main antenna.

Right now I am using a Radio Shack (VU-120RX)

Should I get a higher grade main antenna or just get a VHF only for channel 11 and combine it to my main antenna.

Right now I am using a Radio Shack (VU-120RX)
I would try to aim for channel 11 and see if the other stations are still OK.

A gain chart for the VU-120RX is here : http://www.hdtvprimer.com/ANTENNAS/comparing.html

Hank3:
If it weren't for WTWC on channel 2, I would have just recommended a couple of medium distance antennas aimed in your 2 major directions and combined with a splitter. I think I would also go with professional installation in your case. If you forget about the stations over 50 miles, the smaller antennas would allow you to do an eave or wall-mount possibly using a j-mount with a mast. Any chance WTWC is going to move post transition? If so, you could just set up for the near future and forget about them for now, because all the rest are UHF.
Here is some good info on antennas:

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

I would try to aim for channel 11 and see if the other stations are still OK.

A gain chart for the VU-120RX is here : http://www.hdtvprimer.com/ANTENNAS/comparing.html

I am aimed directly at 11.1 and it still drops out. the other stations are good 99% of the time with this aiming.

Can a UHF only antenna be aimed at 11.1 and combined with my UHF/VHF combo?

After 2 months of an XG91, I've sent it back to Antenna's Direct. In my location, zip 02891, Westerly RI, it is no better than the Radio Shack antenna. No antenna I have tried is any better on UHF than the RS with it's measly gain of 8dB on UHF. I am now a believer in the theory that there is only x amount of signal in a given area, and all the antennas in the world are not going to be of much help. Anyone who wants to come on over and prove me wrong is more than welcome. By the way, I think the CM 4228 is almost as good as the RS, maybe equal. The XG91 is about equal to the RS, in my specific location.

Hank3:
If it weren't for WTWC on channel 2, I would have just recommended a couple of medium distance antennas aimed in your 2 major directions and combined with a splitter. I think I would also go with professional installation in your case. If you forget about the stations over 50 miles, the smaller antennas would allow you to do an eave or wall-mount possibly using a j-mount with a mast. Any chance WTWC is going to move post transition? If so, you could just set up for the near future and forget about them for now, because all the rest are UHF.
Here is some good info on antennas:

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

I have heard from the members who post in the local thread that a couple stations will be strengthening their signals come February. I'm gonna wait for September when DirecTV does their rollout and see if our city gets the local HD channels. If we do, I'll if the picture quality is good enough. If it's subpar or we simply just don't get the HD channels by that time, I'll go with an antenna post transition. Thanks for the suggestions on two medium antennas. And I'm thinking more and more that a pro-install would be best :)

scsiguy72,
I did a quick peak at TVFool.com, and notice that NBC is your only VHF station, although ABC is moving back to VHF-7 next Feb., so you'll want this fixed.

Your problem sounds like a poor VHF section, but the signal levels in TVFool aren't low enough to give marginal reception unless something else is wrong. Earlier responses talked about pre-amp settings, insuring both UHF and VHF amps are on. I wonder if there might be something wrong at the antenna.

Without seeming to insult, did you assemble it properly? There should be separate feed lines from the UHF section (corner reflector Yagi) and VHF section (angled LPDA), and those feed lines can only touch antenna elements and their collection point, where you attached the balun. I've seen a lot of LPDAs with improperly assembled feedlines, ranging from disconnected to trapped in the mast clamp (grounded).

You should have enough antenna for the signal TVFool predicts, but I also notice the biggest jump I've ever seen between pure zip code and zip + El Padro Dr. That tells me that you might want to input your house's long and lat - exact location - to see if there really is enough signal where you actually need it. VHF channels in the -80dBm range ought to be easy with a large, roof-mounted antenna, like the rest of the stations. Are they really that strong?

Frank

scsiguy72,
I did a quick peak at TVFool.com, and notice that NBC is your only VHF station, although ABC is moving back to VHF-7 next Feb., so you'll want this fixed.

Your problem sounds like a poor VHF section, but the signal levels in TVFool aren't low enough to give marginal reception unless something else is wrong. Earlier responses talked about pre-amp settings, insuring both UHF and VHF amps are on. I wonder if there might be something wrong at the antenna.

Without seeming to insult, did you assemble it properly? There should be separate feed lines from the UHF section (corner reflector Yagi) and VHF section (angled LPDA), and those feed lines can only touch antenna elements and their collection point, where you attached the balun. I've seen a lot of LPDAs with improperly assembled feedlines, ranging from disconnected to trapped in the mast clamp (grounded).

You should have enough antenna for the signal TVFool predicts, but I also notice the biggest jump I've ever seen between pure zip code and zip + El Padro Dr. That tells me that you might want to input your house's long and lat - exact location - to see if there really is enough signal where you actually need it. VHF channels in the -80dBm range ought to be easy with a large, roof-mounted antenna, like the rest of the stations. Are they really that strong?

Frank

I think I Assembled it correctly, but I have no problem taking a second look

I m using a preamp, but I took it off and noticed no differance with or without. I am using a splitter for my back room and I have taken it off also and didn't notice a big differance either.

Should I try something like the CM 3671? I don't mind if that fixes things

After 2 months of an XG91, I've sent it back to Antenna's Direct. In my location, zip 02891, Westerly RI, it is no better than the Radio Shack antenna. No antenna I have tried is any better on UHF than the RS with it's measly gain of 8dB on UHF. I am now a believer in the theory that there is only x amount of signal in a given area, and all the antennas in the world are not going to be of much help. Anyone who wants to come on over and prove me wrong is more than welcome. By the way, I think the CM 4228 is almost as good as the RS, maybe equal. The XG91 is about equal to the RS, in my specific location.

Besides the antenna, location, location, location is extremely important for uhf reception in fringe areas. If, for example the uhf antenna is pointed at the center of a nearby tree canopy, then yes, all antennas are going to perform equally poorly.

Besides the antenna, location, location, location is extremely important for uhf reception in fringe areas. If, for example the uhf antenna is pointed at the center of a nearby tree canopy, then yes, all antennas are going to perform equally poorly.

I have a, more or less, clear shot over the tops of all trees for 1000 feet, or so.

I am aimed directly at 11.1 and it still drops out. the other stations are good 99% of the time with this aiming.

Can a VHF only antenna be aimed at 11.1 and combined with my UHF/VHF combo?

I think the best thing for me now is to get a top grade antenna and start over.

Right now I have a radio shack VU120 RX and I am thinking about changing it out for a Channel Master 3020.

Any comments or suggestions? The VHF band seems to be the problem child for me. UHF is fine.

I have a, more or less, clear shot over the tops of all trees for 1000 feet, or so.
Thats much better than what I got, heh. Have you tried to locate a hot spot by moving the antennas up/down a few feet or to the left/right a few yards ? I know I have some unexplained dead zones. Are you in a valley or on a hill ?

Any comments or suggestions? The VHF band seems to be the problem child for me. UHF is fine.
When looking for vhf antennas, look at the gain chart for it for the specific channel you want, the gain varies a lot over different channels. Some expensive high gain vhf antennas have some channels that are less in gain on those channels I want than a cheaper version. Im sure Channel Master has posted the gain chart somewhere, but quickly searching I couldnt find it.

I think I Assembled it correctly, but I have no problem taking a second look

I m using a preamp, but I took it off and noticed no differance with or without. I am using a splitter for my back room and I have taken it off also and didn't notice a big differance either.

Should I try something like the CM 3671? I don't mind if that fixes things

I think the best thing for me now is to get a top grade antenna and start over.

Right now I have a radio shack VU120 RX and I am thinking about changing it out for a Channel Master 3020.

Any comments or suggestions? The VHF band seems to be the problem child for me. UHF is fine.

Reading this through, I still think you have enough antenna, and something else is getting in the way of VHF reception. Let's start by starting over with what you've got.

Antenna
You have a combo, so there are two antennas whose signals combine before the balun. Do check the feed line layout and connections; I've seen them done wrong. If in doubt, post a pic. It may not be intuitively obvious, or even counterintuitive, but they don't like to touch anythign but active elements and feed points.

Pre-amp
You're using single input, both UHF and VHF amplification. Bypass is completely to see if it's working at all (use UHF) and to check analog on VHF. Insert the pre-amp and power supply and see what changes; you should see a change! Make sure the splitter passes DC, since the pre-amp power comes through the coax. Otherwise everything will degrade when you put the pre-amp back in.

Downlead
I assume good quality, RG6 coax with professionally crimped connectors outside and weather proofing on the connections (at least once things work).

And if you really want one of the best out there, the 3671 fits the bill, but I don't see a need unless you're closer to the Post Office than you let on.

Frank

Reading this through, I still think you have enough antenna, and something else is getting in the way of VHF reception. Let's start by starting over with what you've got.

Antenna
You have a combo, so there are two antennas whose signals combine before the balun. Do check the feed line layout and connections; I've seen them done wrong. If in doubt, post a pic. It may not be intuitively obvious, or even counterintuitive, but they don't like to touch anythign but active elements and feed points.

Pre-amp
You're using single input, both UHF and VHF amplification. Bypass is completely to see if it's working at all (use UHF) and to check analog on VHF. Insert the pre-amp and power supply and see what changes; you should see a change! Make sure the splitter passes DC, since the pre-amp power comes through the coax. Otherwise everything will degrade when you put the pre-amp back in.

Downlead
I assume good quality, RG6 coax with professionally crimped connectors outside and weather proofing on the connections (at least once things work).

And if you really want one of the best out there, the 3671 fits the bill, but I don't see a need unless you're closer to the Post Office than you let on.

Frank

OK for th econnections this is what I see:

The VHF is where the Balun attaches. The UHF has a thin rod that runs down the length of the Yagi. This is not touching the mast or any supports it only touches the elements.

I am using RG6, but I crimped the connections myself. My run is about 40-50 feet.

I go a Preamp from Winegard (can't remember the model) But from what I can tell it doesn't do anything. My signal strength did not change at all with it or without it (measured with my TVs antenna strength meter) Is it support to change?

I have a fairly clear view of the mountain range between me and the Towers.

See post #6438 of this thread for street level maps and antennaweb.org readouts.

Thanks a lot for the help. Could it be something as simple as a bad antenna lead?

How do analog stations in the same location or near the VHF station you are trying to get look? There is a wealth of information in the details of a picture report. Is analog snowy? Does it have wavy lines or dark vertical or horizontal bars? You should see more easily the difference with the preamp removed on the stations. Also removing power from the preamp will make it into an attenuator so you should see the picture degrade noticeably when this is done.
John

John,

That Sounds like a good test. Right now my analog is not great. It's pretty snowy with horizonal lines. My preamp is powered (12V) but if I unplug it I get no signal at all, my screen goes blank and I get the no signal message on my screen. Is that not normal? I will go home tonight and pull the preamp and see if I can tell any differance in the picture quailty in analog.

OK So I have a rooftop installed with a pre-amp and I get everything I need EXCEPT........scsiguy72,

Do you have the FM trap engaged on your pre-amp? You have 2 powerful FM stations less than 20
miles away. I have issues even with UHF reception when strong FM is not addressed; even without amplification. Just a thought.

Good Luck!!
Glen

Not sure I will have to get up on the roof and check. It should be on correct?

I am looking at the specs for my pre-amp:

Gain 29dB VHF; 29 dB UHF
low Noise <3.0 dB VHF; <2.6 dB UHF
Switchable FM Trap (not sure what state this is in)
Internal RF shilding

Antenna craft 10G202

Could it be something as simple as a bad antenna lead?

Even simpler, a bad balun, very common. The wires inside of a balun are very very thin. If the threaded part of the balun turns as you are attaching it, you could very well have a broken balun.

Cpcat,

Thanks for the info. The hard part is finding a 4-way strip combiner.

As for adding the 2 additional UHF antennas would you say the "extra cost" is worth the gain? (Total of 4 in a horizontal stack) That would require a 10' pipe, and then spacing them ~52" apart.

Also, can you post a picture of your quad array?

Thanks!

You'd be better off with a horizontal quad, then you could keep your Funke. I've tried them both, horizontal works best IMO.

Both the dual and quad stack will have some hi vhf gain "through the back" just FYI. If you have a decently strong hi vhf you'll probably still pick it up using the 7777 in combined uhf/vhf mode. I pick up a vhf 12 digital from 55 miles with my current setup.

The 9521 would still probably do it since it's inside the tower and protected by the bearing. My 9521 is still hanging in there.

You'll need the 4-way stripline combiner for the best result. A 4 way splitter in reverse won't work. Believe me, I've tried it. Using 3 two-way splitters does work, but not as well as the 4 way stripline will.

Location is the king!

My installer, has his antenna 15' off the ground next to his home. His roof is made out of metal and he picks up more stations than my horizontal stack at 52' in the air. (Go figure)

Now, if you live near a water tower you could be a winner. Point your antenna directly at the tower. You will pick-up the reflected waves off the tower from the stations. :D (An old trick that actually works) Think of it, as a way to get some free bounced signals.

Besides the antenna, location, location, location is extremely important for uhf reception in fringe areas. If, for example the uhf antenna is pointed at the center of a nearby tree canopy, then yes, all antennas are going to perform equally poorly.

Switchable FM trap........... It should be on correct?
Yes,

I would a least try it; it may or may not make a difference. Any possible overload can wreak havoc on your reception. You should be getting Channel 11 without much problem using your TV Fool street level results.(An exact address or coordinates may be more accurate) KNTV-DT 11 does have a directional signal that is not entirely in your favor; but it looks adeuqate.

[QUOTE=300ohm;14302156]Thats much better than what I got, heh. Have you tried to locate a hot spot by moving the antennas up/down a few feet or to the left/right a few yards ? I know I have some unexplained dead zones. Are you in a valley or on a hill


Yes, I have tried moving across the roof and changing elevations, no sweet spot for me. Someone on one of the other sites describes Westerly, RI as a "reception pit". Thanks for trying to help, 300ohm I am situated on more or less flat terrain, the antenna is about 35 feet above sea level.

OK for th econnections this is what I see:

The VHF is where the Balun attaches. The UHF has a thin rod that runs down the length of the Yagi. This is not touching the mast or any supports it only touches the elements.

A little antenna theory (about all I have), with a reference:
http://www.hdtvprimer.com/ANTENNAS/types.html
Scroll down to Log-periodic Dipole Arrays (LPDA) which is right above Yagi's. You have one of each, a VHF LPDA and a UHF corner Yagi.

Your UHF Yagi has a broad, flat loop (folded dipole) near the reflector that's the only receiving element, the rest are reflectors and directors - gain enhancement. In the diagram, look for the element with two little circles on it. That's where the balun attaches in an isolated Yagi. No balun is needed with 300 ohm twin-lead.

Your VHF LPDA has a completely different feedline, a pair in fact, that connects all elements, criss-crossing from one side to the other with terminals at the short end. These feedlines should only touch their half of the elements, and one side of the VHF balun. Again, no balun is needed with 300 ohm twin-lead.

Based on these layouts, the only "thin rod that runs down the length" would be a pair of feedlines, one from each side of the folded dipole to the UHF-VHF junction where the balun attaches. (I assume you don't mean the boom that mounts the elements.)

I am using RG6, but I crimped the connections myself. My run is about 40-50 feet.

Good for you! I'm lazy and my antenna's indoors so I use twist-ons. However, look into coax-seal or some other weatherproofing once you're happy with your set-up and it'll retain it's performance much longer.

I go a Preamp from Winegard (can't remember the model) But from what I can tell it doesn't do anything. My signal strength did not change at all with it or without it (measured with my TVs antenna strength meter) Is it support to change?

I have a fairly clear view of the mountain range between me and the Towers.

See post #6438 of this thread for street level maps and antennaweb.org readouts.

Thanks a lot for the help. Could it be something as simple as a bad antenna lead?

John,

That Sounds like a good test. Right now my analog is not great. It's pretty snowy with horizonal lines. My preamp is powered (12V) but if I unplug it I get no signal at all, my screen goes blank and I get the no signal message on my screen. Is that not normal? I will go home tonight and pull the preamp and see if I can tell any differance in the picture quailty in analog.

Pre-amps are great when you need them, but you may not. Digital signals are threshold-sensitive, and if you're above threshold, there's no benefit, as you report. That's why ctdish and I suggested using analog stations to verify pre-amp function. You will see the pre-amp affect in analog stations.

Pulling power kills the signal, as you discovered. You have to bypass the pre-amp at the mast.

Digital Rules had good advice about the FM trap, too.

Which brings me to 300ohm's thought - bad parts. When you go up, take a known good balun and length of terminated coax, maybe a barrel connector (female-to-female) to bypass the pre-amp and make the coax an extension cord.

The easy test for the balun is to wire a pair together, 300 ohm to 300 ohm, so you have F-connectors at the ends. Insertion of two baluns may cause a 3-8dB loss, but a bad balun will kill the signal. Do the same with your length of coax so you know you have some good reference parts with you at the mast. The baluns between the pre-amp and its power supply must also pass DC.

And while you're up there, take some pictures ... we have great imaginations, but you don't want to chase imaginary problems! At the same time, pictures answer questions we can't think to ask.

Frank

Location is the king!

My installer, has his antenna 15' off the ground next to his home. His roof is made out of metal and he picks up more stations than my horizontal stack at 52' in the air. (Go figure)


Hmm, I have to renew the roof on my garage. I was thinking of using a black metal roof spaced above the old shingle roof on the south west side for some free solar passive heating (and its cheaper than shingles). This gives me another reason to use it. The only trouble is, I have no stations perpendicular to any of the 4 sides of the roof, any way I do it, it would be facing off angle to a station. :( Is the installer picking up off angle stations well too ?

I put together a rather crude double bay G-H, 2x4 + chicken wire reflector not very smooth, etc. Connected to a 32" Vizio ATSC via a CM 7777. Managed to get very clear reception for WLNY and WFTY, both Long Island stations 210 miles away. I'm on the MD coast near Ocean City so its about 10 miles over land and the rest over water. Antenna pointed 330 deg, tilted back abt 15 deg.

Managed to get very clear reception for WLNY and WFTY, both Long Island stations 210 miles away.
Holy smoke, was that on Tuesday ? It was some very good dxing on Tuesday here.

It was Thursday 7/17 about 5 PM. Also saw WTFX HD out of Philly, about 110 miles away. Should also note that antenna height was 15 feet.

Was looking for a NBC HD station to watch Olympics as Mediacom does not carry NBC HD! Will try Baltimore station this weekend.

I put together a rather crude double bay G-H, 2x4 + chicken wire reflector not very smooth, etc
Heh, normally a not smooth chicken wire reflector doesnt give good results. In your case, I wouldnt touch a thing on it. :p Also dont breathe to hard on it, it may distort its properties. :p
My DBGH 12 colinear pair reflector works very well, but I have yet to get anything from 210 miles away.

Its kind of like the Simpsons Episode where Homer develops a perfect chiropractic back device from a bent up trash can that worked so perfect, the chiropractic doctors destroyed it.

does anyone recognize this bad boy by chance?

http://farm4.static.flickr.com/3076/2681499166_59c4a20f00.jpg?v=0

i'm ready to leave cable TV behind and go OTA. i've got this beauty on my roof but it is probably +20 years old. the cable was cut sometime before I lived here but they left the (ungrounded) mast and antenna up on the roof. i'd would need to get a matching transformer but there is no obvious place on the antenna to attach it. Then i would still need to run the cable, ground it, and then get it into my house (probably ~$40 and lots of work).

however, i am also only 9 miles away from a transmitter that is broadcasting 14 UHF digital signals. my backup plan is to just get a Silver Sensor and stick it in my attic (~ $25 and very little work).

should i salvage the old one or just get an inexpensive indoor antenna since i am so close?

Looks like and old Radio Shack VHF only antenna. V-75 or V-90?

In any event that antenna is not likely to be suitable for most, if not all of your HDTV reception needs. Most HDTV channels are broadcast on the UHF channels while only a handful are in the VHF range.

Try visiting tvfool.com (don't forget the www at the beginning of the address? and see what it recommends for your home.

Looks like and old Radio Shack VHF only antenna. V-75 or V-90?

I'm also pretty sure it's RS; I used to sell these things as a callow youth. But with 12 elements, it's higher than that, IMO -- possibly V-110 or V-120. Compare today's VU-90, which has eight VHF elements.

TVFool is a good idea for the OP. So is taking that old thing down off the roof. An ungrounded antenna and mast outdoors are way too tempting to Thor, God of Thunder.

Anyone remember the Channel Master 4251 parabolic dish antenna (https://www.vancebaldwin.com/webwiz/wwiz.asp?wwizmstr=WEB.SEE&partnumber=105049)? I found a listing for it (https://www.vancebaldwin.com/webwiz/wwiz.asp?wwizmstr=WEB.SEE&partnumber=105049) at a place called Vance Baldwin Electronics but it shows 0 in stock. While I realize it hasnt been made in a while, which is why they have 0 stock, I'm just surprised to see it listed on a commercial website. It makes me wonder if they recently had stock of it.

Anyway, for those who are familiar with it, was the performance as great at it was supposed to have been? I've read that the CM 4251 would give 4 CM 4228's ganged-together a run for their money...which is unbelievable!

Why is there no "build your own 4251" page yet? Granted I know nothing about engineering an antenna, but from the photos it seems fairly straightforward...more or less a single bay antenna in the center of a parabolic screen. I'm guessing there are technical details as to the bow/curvature of each rung in the dish, as well as how its all coupled together, but otherwise, it probably not much more complex than any of the others.

Anyone remember the Channel Master 4251 parabolic dish antenna (https://www.vancebaldwin.com/webwiz/wwiz.asp?wwizmstr=WEB.SEE&partnumber=105049)? I found a listing for it (https://www.vancebaldwin.com/webwiz/wwiz.asp?wwizmstr=WEB.SEE&partnumber=105049) at a place called Vance Baldwin Electronics but it shows 0 in stock. While I realize it hasnt been made in a while, which is why they have 0 stock, I'm just surprised to see it listed on a commercial website. It makes me wonder if they recently had stock of it.



That puppy was one of highest gain antenna's out there back in the day. Here's a great link: http://www.rocketroberts.com/cm4251/cm4251.htm

Check out this "Channel Master 4251 Tribute Site":
http://www.rocketroberts.com/cm4251/cm4251.htm

Also look at this link for performance comparisons:
http://atechfabrication.com/tests/04-17-01_test_results.htm

In the 70's I used to own the 5 foot Layfette Radio Electronics parabolic he has pictured on that site. IIRC, it cost me about $25 and a 200+ mile round trip to their Long Island store. It performed very well at channels above about 35. But I think my present DBGH performs better at channels 20 to about 35 than it did. I think the main reason they discontinued the parabolic models is that present day costs would make it appealing only to die-hard dx'ers and not to the average Joe. Another downside, due to their large size, was they caught a lot of wind. They needed serious guy wiring. Mine was destroyed in a strong storm.

On another note, I still have that Blonder Tongue (or a clone of it) LPDA antenna pictured next to it. It was plated steel, but the plating is long gone and is now just rust plated, heh.

do you have your DBGH mounted outside?

i'm aiming for channels 18-30 at about 60 miles so i went with the wineguard 8800 and had good results, but the first moderate wind storm turned it into a mess and not it receives nothing but a very local channel (yes i tried replacing everything to make sure it was the antenna)

i've got some 4251s on towers around here and was considering getting one although it would come at some expense as i have to hire a truck to get it down, people are nice enough to give the dish away but just are not keen on letting me climb up there on their property.

thinking about trying the DBGH but didn't know if i could get one to hold up to the elements. was considering the cm 4228 but like the other alternatives, the below ch30 performance is blah....

In the 70's I used to own the 5 foot Layfette Radio Electronics parabolic he has pictured on that site. IIRC, it cost me about $25 and a 200+ mile round trip to their Long Island store. It performed very well at channels above about 35. But I think my present DBGH performs better at channels 20 to about 35 than it did. I think the main reason they discontinued the parabolic models is that present day costs would make it appealing only to die-hard dx'ers and not to the average Joe. Another downside, due to their large size, was they caught a lot of wind. They needed serious guy wiring. Mine was destroyed in a strong storm.

i've got some 4251s on towers

I recently became aware of towers and mounting antennas on them as opposed to just mounting it on ones roof...which is great since I cant get up on my roof to mount an antenna.

Where can the average consumer get a tower of good quality...and once one acquires a tower, how does one put it up. I would assume the antenna and everything has to go on while its laying down, and then you just lean it up...does it still have to be secured to the side of ones house? I've heard of some people pouring a concrete base...would the tower then be able to be completely freestanding and have it work just as well as if it were attached to the house?

do you have your DBGH mounted outside?
i'm aiming for channels 18-30 at about 60 miles so i went with the wineguard 8800 and had good results, but the first moderate wind storm turned it into a mess and not it receives nothing but a very local channel (yes i tried replacing everything to make sure it was the antenna)

Yes, its outside. I made the 12 pair colinear rod model, so its very wind resistant. But a 2 X 4 inch mesh model would also be very wind resistant and offers a hair more gain and is easier to construct than colinear rods.
http://img135.imageshack.us/img135/8994/dscn0266486x648en7.jpg
Its made from 1 inch pvc with a broom handle in the middle and a steel u-channel on the back. Its very stiff, heh. Overall dimensions are about 2 foot by 5 foot. According to the net gain charts, with the DBGH 2 X 4 inch grid model, you should get about .5db more gain than the 8800 at channel 18, and about 1.5db more gain at channel 30 than the 8800. Keep in mind, the 8800 is the best available consumer antenna available for sale for channel 18, per the charts on hdprimer.

i've got some 4251s on towers around here and was considering getting one although it would come at some expense as i have to hire a truck to get it down
Depending on the cost of the truck, it could be a good deal. Ive heard 4251s going for $150 plus shipping on ebay, when and if you can find one.

Where can the average consumer get a tower of good quality...
Are you going to install it yourself ? Rohm makes good ones. I like the models that crank up and down. Keep in mind, youre looking at spending in the ball park of $750. If you want to go cheap, look in the classifieds, sometimes you can get one for free by hauling it away.

I have eight of these parabolic antennas sitting in my backyard.

I fooled around with these bad boys and decided NOT to use these on my new install. Actually, the Antennas Direct 91XG was able to pull in the digital channels with higher signal strength. However, the 4251 was MUCh better at the Analog signals.

Bring your pick-up to Northwest OH, and you can have these monsters. :D

Anyone remember the Channel Master 4251 parabolic dish antenna (https://www.vancebaldwin.com/webwiz/wwiz.asp?wwizmstr=WEB.SEE&partnumber=105049)? I found a listing for it (https://www.vancebaldwin.com/webwiz/wwiz.asp?wwizmstr=WEB.SEE&partnumber=105049) at a place called Vance Baldwin Electronics but it shows 0 in stock. While I realize it hasnt been made in a while, which is why they have 0 stock, I'm just surprised to see it listed on a commercial website. It makes me wonder if they recently had stock of it.

Anyway, for those who are familiar with it, was the performance as great at it was supposed to have been? I've read that the CM 4251 would give 4 CM 4228's ganged-together a run for their money...which is unbelievable!

Why is there no "build your own 4251" page yet? Granted I know nothing about engineering an antenna, but from the photos it seems fairly straightforward...more or less a single bay antenna in the center of a parabolic screen. I'm guessing there are technical details as to the bow/curvature of each rung in the dish, as well as how its all coupled together, but otherwise, it probably not much more complex than any of the others.

I purcahsed my Rohn 20 for $79 a section (NEW). If you need some, my distributior has 500' and I will extend dealer cost to you...

Use caution when talking to the installers, as I discovered they are REALLY infating the prices of tower, saying the raw materials are so expensive. This is true, but paying over $110 a section of Rohn 20 is just a ripoff.

Are you going to install it yourself ? Rohm makes good ones. I like the models that crank up and down. Keep in mind, youre looking at spending in the ball park of $750. If you want to go cheap, look in the classifieds, sometimes you can get one for free by hauling it away.

I have eight of these parabolic antennas sitting in my backyard.

I fooled around with these bad boys and decided NOT to use these on my new install. Actually, the Antennas Direct 91XG was able to pull in the digital channels with higher signal strength. However, the 4251 was MUCh better at the Analog signals.

Bring your pick-up to Northwest OH, and you can have these monsters. :D

hmmm...where at in NW OH? I live in PA...though I dont have a pickup so I'd have to dissassemble one...or two (if you're giving them away). :D

Hey, 300ohm -- someone in Phoenixville, PA on Bridge Street west of Main Street has a Hoverman like yours up... except I think theirs must be an original, because it looks like it's been there a good long while.

bbthut's big LPDA looks like it is in surprisingly good shape; most of the ones I see around here have elements missing or bent at crazy angles.

Hey, 300ohm -- someone in Phoenixville, PA on Bridge Street west of Main Street has a Hoverman like yours up... except I think theirs must be an original, because it looks like it's been there a good long while.

Is it a double bay or single bay ? If its a single bay, its probably the one Radio Shack sold way back when. If its a double bay commercial, it may be the Antenna Craft model, fairly recent and sold by SummitSource :
http://www.summitsource.com/antennacraft-8-bay-uhf-antenna-hdtv-guaranteed-to-out-perform-all-other-outdoor-18-elements-tv-aerial-for-local-offair-digital-fringe-reception-red-zone-part-super-g1483-with-coaxial-cable-p-6356.html

But the trouble with the commercial designs, is they have way too few reflectors. The Hoverman needs a good reflector for good gain.

Hmm.....could one buy that model and add reflectors? How hard could that be?

It would be even easier and have more gain by adding 1 by 2 mesh to it. But if youre going to that trouble, save the expense and shipping by building one yourself.
http://www.digitalhome.ca/ota/superantenna/

Someone was kind enough to give me a Medium or maybe large (it's about 8 or so feet long) directional UHF/VHF antenna. A few of the elements are either gone or were bent and when I tried to straighten them they cracked.

The antenna works well but I wouldnt mind replacing the missing elements to see if it could get any better. The elements are aluminum, but I dont think aluminum tubing is sold at the local home depot or other hardware store? I'm hesitant to mix metals, as that can contribute to corrosion. Still, does anyone here have ideas on what I could replace them with?

Someone was kind enough to give me a Medium or maybe large (it's about 8 or so feet long) directional UHF/VHF antenna. A few of the elements are either gone or were bent and when I tried to straighten them they cracked.

The antenna works well but I wouldnt mind replacing the missing elements to see if it could get any better. The elements are aluminum, but I dont think aluminum tubing is sold at the local home depot or other hardware store? I'm hesitant to mix metals, as that can contribute to corrosion. Still, does anyone here have ideas on what I could replace them with?

Your time would have to be worth near zero or less to make that worth doing, since you can buy a new, six foot long Winegard PR-9022 for about $30, or a ten foot Winegard PR-9032 or an 8 foot PR-7015 (U/V) for about $40.

Edit/Update:

I just found nwiser's TV Fool, post-transition list in his local thread and see that he DOESN'T have line of sight reception from ten of the eleven transmitters that are within ten miles of him, even though they are in four distinctly different azimuth directions. Does nwiser live in the bottom of a well?

A few of the elements are either gone or were bent and when I tried to straighten them they cracked.... does anyone here have ideas on what I could replace them with?Keep an eye out for other broken antennas people in the neighborhood have taken down. Often they will give them to you just to get rid of them. Maybe you will collect enough elements to make a good antenna. Still, like Mike said, it's not really worth the time it will take to do it.

Speaking of broken antennas...

The house we bought had a Channel Master antenna on it which was damaged when taken down for a new shingle job.
The longest low VHF elements were sheared off from their rivets. I'm thinking of salvaging this antenna and need to know:

1) the long rods still seat in the holders but are just set in there. What is the right glue? solder? tape? to bond aluminum to aluminum?

2) in our area we'll no longer have low VHF channels after Feb. 2009. Are the longest elements of this antenna even necessary at that point? Should I just take them off?

Thanks in advance.

Antennas I have repaired all have had the elements held in by riveted braces. To do a repair I drill the rivet out, take an element of the same length as the broken one and drill a hole like the original one had and reassemble the brace and element to the boom with a stainless screw, lock and nut. Connecting to the old element stub is not likely to work.
John

I'm no expert, but at this point I would say if you won't need low-VHF leave the elements off. The longest of the elements of a LPA style antenna are probably tuned for channels 2-3 and probably would do little if anything for channels 5-6 even.

1) the long rods still seat in the holders but are just set in there. What is the right glue? solder? tape? to bond aluminum to aluminum?
What I do is insert a short piece of solid aluminum rod that fits into the 3/8 inch aluminum tubing and then drill and pop rivet the two.

2) in our area we'll no longer have low VHF channels after Feb. 2009. Are the longest elements of this antenna even necessary at that point? Should I just take them off?

I'm no expert, but at this point I would say if you won't need low-VHF leave the elements off. The longest of the elements of a LPA style antenna are probably tuned for channels 2-3 and probably would do little if anything for channels 5-6 even.

Thats what I thought until I modeled my vee boom LPDA antenna.

I will need channels 6 and 12 only after the transistion, so I also figured I could get rid of the elements longer than 1/2 wavelength for channel 6, minus leaving the last longer one before channel 6 wavelength, as a reflector for channel 6. That would make the monster more compact.
But Im afraid I cant do it. Modeling shows cutting those large elements decreases the gain on both channel 6 and 12, and Ill need every bit I can get.

So, cutting without modeling your antenna, you take the risk of significantly reducing the gain on the particular channel you may want.

I just found nwiser's TV Fool, post-transition list in his local thread and see that he DOESN'T have line of sight reception from ten of the eleven transmitters that are within ten miles of him, even though they are in four distinctly different azimuth directions. Does nwiser live in the bottom of a well?


haha well.... I do actually live near the bottom of a hill...probably lower than much of Pittsburgh. :o

leaving the last longer one before channel 6 wavelength, as a reflector for channel 6.What if you repositioned the last remaining element so that it would create an in-phase reflection at channel 6? That would be do-able since the lower VHF dipoles would be gone. I would think it would then act as a real reflector, and increase gain.

Has anyone bought the new ClearStream 2 by Antennas Direct?

Has anyone bought the new ClearStream 2 by Antennas Direct?

I'd be inerested to know as well. I wouldnt mind seeing some modeling data on it and it's larger brother. Isnt the Clearstream 4 suposed to be as good if not better as the DB8 as far as multidirectionality and such, only smaller? Makes one wonder though why theres not a Clearstream 8....

What if you repositioned the last remaining element so that it would create an in-phase reflection at channel 6? That would be do-able since the lower VHF dipoles would be gone. I would think it would then act as a real reflector, and increase gain.

That would be nice if it worked, it would decrease my boom size from 105 inches to 55 inches. But it aint to be so. Modeling shows in that scenario that I can get the original gain amount on channel 6, but then I lose 3.2 db on channel 12. I cant afford to lose that much. My channel 6 is projected to be at -86.3dbm and channel 12 at -94.9dbm.

I'd be inerested to know as well. I wouldnt mind seeing some modeling data on it and it's larger brother. Isnt the Clearstream 4 suposed to be as good if not better as the DB8 as far as multidirectionality and such, only smaller? Makes one wonder though why theres not a Clearstream 8....
Well, the Clearstream 1 shows a peak gain of 8 dBi. That means if its well designed, Clearstream 2 would have a peak gain of about 10.5 db and the Clearstream 4 would have a peak gain of around 13 db. For $129, thats just plain pitiful. The CM 4228 has more gain (even without being redesigned for 2009) without amplification for only around $60 and isnt that much larger and may in fact weigh less.

Edit: Just found the page for the Clearstream db quotes: http://www.antennasdirect.com/HDTV_antennas.html

They claim 10.3dbi for the Clearstream 2, which sounds about right if 8dbi is for Clearstream 1. But they claim 14.8 db for the Clearstream 4, which sounds very suspect.

I've finally had some genuine success, as a dweller in a ground-floor condo unit, obtaining good reception using a 4221 clone placed indoors. I can obtain signal from all 14 Seattle-Tacoma local stations (34 subchannels in all), a feat I had not imagined achieving without a rooftop install that would be a bit more complicated.

For the fourteen channels, my signal quality (measured by the Zenith DTT900 signal meter) for many stations is roughly 7 to 8, in a few cases it's it's down around 5. There are some dropouts and fluctuation, but this is the best reception I've obtained indoors. Would an antenna preamplifier (i.e. Channel Master 7777) help smooth out those fluctuations? Keep in mind, the transmitters are between 11 and 23 miles away, but I am aware of the risk of amplifier overload.

Many kind thanks for your suggestions to stabilize reception.

I've finally had some genuine success, as a dweller in a ground-floor condo unit, obtaining good reception using a 4221 clone placed indoors. I can obtain signal from all 14 Seattle-Tacoma local stations (34 subchannels in all), a feat I had not imagined achieving without a rooftop install that would be a bit more complicated.

For the fourteen channels, my signal quality (measured by the Zenith DTT900 signal meter) for many stations is roughly 7 to 8, in a few cases it's it's down around 5. There are some dropouts and fluctuation, but this is the best reception I've obtained indoors. Would an antenna preamplifier (i.e. Channel Master 7777) help smooth out those fluctuations?

Probably not. Your best bet is to locate the hottest hot spot in the room or rooms.
Are you getting signal quality numbers on your DTT900 or are you just guestimating from Good/Bad/Maybe bar ?

With the donated antenna, I got what appears to be fairly heavy duty mast poles...one 4 ft section and one 10 ft section. Both sections appear to be fairly thick and roughly 1" in diameter. I would like to get another 20 or so feet but dont believe theres anywhere locally I can get it. I picked up a 5 ft mast pole from my local Lowes and it looks so flimsy I think it would bend in a mild breeze.

Where can I get really good quality/heavy duty antenna masts that wont bend over in a moderate wind?

You could use black pipe, stuff is super strong, but wieghs a ton.
You'd need some good guy wires.
:)

You could use black pipe, stuff is super strong, but wieghs a ton.
You'd need some good guy wires.
:)

Black pipe may be strong, but it is not really rated for strength. There are much stronger alloys available.

Anybody tried these antennas yet? Or what are your thoughts?

http://cgi.ebay.ca/NEW-AMPLIFIED-VHF-UHF-OUTDOOR-HDTV-HD-ROTOR-TV-ANTENNA_W0QQitemZ160265925900QQihZ006QQcategoryZ149957QQssPa geNameZWDVWQQrdZ1QQcmdZViewItem

Anybody tried these antennas yet? Or what are your thoughts?

http://cgi.ebay.ca/NEW-AMPLIFIED-VHF-UHF-OUTDOOR-HDTV-HD-ROTOR-TV-ANTENNA_W0QQitemZ160265925900QQihZ006QQcategoryZ149957QQssPa geNameZWDVWQQrdZ1QQcmdZViewItem

Looks like a cute piece of junk that will be just what some people need.

The eBay description was written by a mass marketer who has no idea what an antenna is or does, so scrutinizing that page's contents doesn't tell us much.

It looks small enough to fit in someone's closet, which is nice, and the fact that its "spec" column says it passes signals from 40 to 862 MHz means that they copied those boundaries from some cable TV product, so I can't even say for sure that the amplifier passes VHF, which is my only real concern.

While its folded dipole is too short to be optimized for hi-band UHF, it might work OK in an urban setting IF the amplifier doesn't block the highband VHF.

The eBay page says that Radio Shack, Best Buy and Circuit City sell them for $115 to $125, but they aren't listed on any of those sites, and I wasn't able to narrow my Google search enough to find any "titan" product that seemed to match it.

I picked up a 5 ft mast pole from my local Lowes and it looks so flimsy I think it would bend in a mild breeze.

Where can I get really good quality/heavy duty antenna masts that wont bend over in a moderate wind?

Yeah, Ive seen that flimsy 5 foot mast pole Lowes sells for almost $7. Take it back and go to their garden / fencing section. You can get the 10 foot chain link fencing pole that is the same size OD and much stronger for a little over $9. If youre going to use 34 ft of pole, youre going to need a good guy wire system.

Anybody tried these antennas yet? Or what are your thoughts?

http://cgi.ebay.ca/NEW-AMPLIFIED-VHF...QQcmdZViewItem
It looks like a good antenna for a camper. But it certainly is a much poorer performer than the antenna setup shown in their "before" picture, heh.

Anyone with suggestions for routing RG-11 off balun of this antenna? Could I cable tie it to the lower reflecter and then to the mast, or should I loop it back and secure it to the boom then down the mast?

- & I answer my own question here .
http://www.avsforum.com/avs-vb/showthread.php?t=1028231&highlight=xg91+routing

Anyone with suggestions for routing RG-11 off balun of this antenna

I've never connected RG-11 directly to an antenna. it makes servicing it too awkward. I usually use a short piece of RG-59 to mate the RG-11 with the antenna's "F" terminal.

Anybody tried these antennas yet? Or what are your thoughts?

http://cgi.ebay.ca/NEW-AMPLIFIED-VHF-UHF-OUTDOOR-HDTV-HD-ROTOR-TV-ANTENNA_W0QQitemZ160265925900QQihZ006QQcategoryZ149957QQssPa geNameZWDVWQQrdZ1QQcmdZViewItem

Go to the first post in the How to Build ... thread, click on the link.
http://www.avsforum.com/avs-vb/showthread.php?t=798265
Compare the antenna he replaces in step 9 to what's being sold on eBay. I think anyone who buys this will share his thoughts upon replacement with a real TV antenna.

Do these things have any valid application?

Frank

Live in relatively flat Iowa. Approx. 60 miles max to the most distant tower - most are 55 miles @ 263 degrees. MY antenna will be approx. 18 ft in air. Which would be better the Cm 4221 or the Antennacraft U-4000? or should I be looking at different antennas? The channels I will receive are 28 to 50.

Yeah, Ive seen that flimsy 5 foot mast pole Lowes sells for almost $7. Take it back and go to their garden / fencing section. You can get the 10 foot chain link fencing pole that is the same size OD and much stronger for a little over $9. If youre going to use 34 ft of pole, youre going to need a good guy wire system.


Thanks...I went by Lowes earlier and saw the fence pole you are talking about. It does indeed look sturdier than the 5 ft pole they have sitting by their antennas, so I'm still probably gonna get 2 of them unless anyone else knows of a place to get better ones. I just remeasured the free one and the pole is 1 and 1/4 inch wide, and the metal is approximately 2mm thick.

If I get two 10 ft sections from lowes, I'm probably gonna use the shorter heavy duty section I got for free to set the antenna and rotator on, then the Lowes stuff, then the longer free heavy duty section on the bottom. I'm planning on attaching it to the side of my house via brackets, not on top of my roof...so do I still need guy wires? Would it make sense to pour a shallow concrete base for it?

As my TVfool info showed a few pages ago, I live less than 15 miles from most of my local towers but my antenna is directional and after Feb 09 I'm planing on having it aimed at a VHF transmitter roughly 45 miles away (which is more or less where its aimed now) so that I can pick up the Fox station I like to watch. I pick up all my locals ok but since the antenna isnt aimed at them one can understand why they arent all coming in at 90%+. Would a preamp help?

I get the impression that the ChannelMaster 7777 is the best preamp...or is it just the most popular?

Also, as far as rotators go, what's the general consensus on the best one for the price paid?

I'm planning on attaching it to the side of my house via brackets, not on top of my roof...so do I still need guy wires? Would it make sense to pour a shallow concrete base for it?

If you have more than about 7 - 10 feet of unsupported mast, then I would guy wire it. A concrete base for it is good. Also with the chain link fence pole section, youll want to also get the set screw connector there too for joining the two sections.

If your total cable length is over 40 ft, then a preamp makes sense. The ChannelMaster 7777 is the best available low noise residential preamp for UHF, unless you are willing to spend a few hundred on a lower noise model.
If you want to spend a little less, the Channel Master Spartan series are also excellent preamps.

There is no way you can attach RG-11 to the 91XG. I would use RG6 off the antenna into your pre-amp, and then convert to RG-11 down.

RG-11 is difficult to work with. However, you can get it for $30 (100ft) with ends on it from Rwantenna on Ebay. :)

Anyone with suggestions for routing RG-11 off balun of this antenna? Could I cable tie it to the lower reflecter and then to the mast, or should I loop it back and secure it to the boom then down the mast?

- & I answer my own question here .
http://www.avsforum.com/avs-vb/showthread.php?t=1028231&highlight=xg91+routing

I've finally had some genuine success, as a dweller in a ground-floor condo unit, obtaining good reception using a 4221 clone placed indoors. I can obtain signal from all 14 Seattle-Tacoma local stations (34 subchannels in all), a feat I had not imagined achieving without a rooftop install that would be a bit more complicated.

For the fourteen channels, my signal quality (measured by the Zenith DTT900 signal meter) for many stations is roughly 7 to 8, in a few cases it's it's down around 5. There are some dropouts and fluctuation, but this is the best reception I've obtained indoors. Would an antenna preamplifier (i.e. Channel Master 7777) help smooth out those fluctuations? Keep in mind, the transmitters are between 11 and 23 miles away, but I am aware of the risk of amplifier overload.

Many kind thanks for your suggestions to stabilize reception.
Although indoor location loss makes overload less likely,
you should avoid high gain Preamps like the CM7777.
W-G HDP-269 has much higher overload resistance:
http://www.summitsource.com/product_info.php?ref=1&products_id=5577
Although Preamps are primarily used to overcome downlead cable loss,
they can also improve overall sensitivity IF overload desensitization can be avoided.

It's worth a try....

There is no way you can attach RG-11 to the 91XG. I would use RG6 off the antenna into your pre-amp, and then convert to RG-11 down.

RG-11 is difficult to work with. However, you can get it for $30 (100ft) with ends on it from Rwantenna on Ebay. :)
Since Preamp Gain reduces the effect of downlead cable loss,
there would be very little difference between using RG-6 and RG-11.

RG11 is unneccessary for runs under 250'...

Understood, but it has nice bragging rights. ;)

RG11 is unneccessary for runs under 250'...

If that's what you want, check into some 5/8-inch or larger Heliax cable:
http://www.rfparts.com/heliaxcoax.html

If that's what you want, check into some 5/8-inch or larger Heliax cable:
http://www.rfparts.com/heliaxcoax.html

I can't find an F connector for 1 5/8" Heliax. That big stuff is all 50 ohms!

I can't find an F connector for 1 5/8" Heliax. That big stuff is all 50 ohms!

You want 75ohm cable...NOT 50ohm...

I can't find an F connector for 1 5/8" Heliax. That big stuff is all 50 ohms!

Details, Details.........:rolleyes:

You want 75ohm cable...NOT 50ohm...
With typical antenna VSWR of 3:1 and ATSC Tuner VSWR not much better,
50 vs 75-ohm won't make much difference....
might even be better.....

I have a station that currently shows no signal during the day, and 20-30 percent every night, but not enough to lock on (on my STB, it takes about 50 percent to lock on) and it does lock on occasionally a couple nights a week. TVfool lists it's signal for me at -127.9 . This station will be increasing it's power after transition, and my signal for this station after transition is listed at -113.1. Roughly, how much of a difference in reception might this translate into? The station is goin from 48 KW to 1000 KW

I have a station that currently shows no signal during the day, and 20-30 percent every night, but not enough to lock on (on my STB, it takes about 50 percent to lock on) and it does lock on occasionally a couple nights a week. TVfool lists it's signal for me at -127.9 . This station will be increasing it's power after transition, and my signal for this station after transition is listed at -113.1. Roughly, how much of a difference in reception might this translate into? The station is goin from 48 KW to 1000 KW

Every 3db is a doubling of signal power. (does this rule apply to TVFool figures ?) So 127.9 minus 113.1 equals 14.8, almost 15db. So that would be 3 X 3 x 3 x 3 x 3 = about 243 times more signal. Even at -113.1dbm, you may not get that station consistantly.

I finally got around to taking pictures of my 91XG/VIP306 setup.

http://bp3.blogger.com/_mu3nxD8i5WE/SJZuTJGbx4I/AAAAAAAAAA0/Y8D1OJ9MzRA/s1600-h/100_3622.JPG

This is a pretty potent combo for deep fringe reception.

I finally got around to taking pictures of my 91XG/VIP306 setup.

http://bp3.blogger.com/_mu3nxD8i5WE/SJZuTJGbx4I/AAAAAAAAAA0/Y8D1OJ9MzRA/s1600-h/100_3622.JPG

This is a pretty potent combo for deep fringe reception.
And, it appears, the birds like it, too. :)

No rotor???

No rotor???
Some of us don't really have two good locations to aim at. All of mine, for example, are pretty much in the same area:

http://homepage.mac.com/ziggy29/Media/TVF-pre2009.jpg

Just point a stacked 91XG and YA-1713 to maximize KNVA and KTBC and I'm set. The YA-1713 is primarily for when KTBC returns to channel 7 in February.

No rotor???

Nope. All of our towers are in the same direction. I get ABC, NBC, CBS, Fox, and PBS in HD.

You may want to attach the coax to your mask pipe, as it is causing additional stress on the antenna leads. This will break in a matter of time.

Also, route the coax out the back of your 91XG.

Nice set-up, but cable management is POOR.

I finally got around to taking pictures of my 91XG/VIP306 setup.

http://bp3.blogger.com/_mu3nxD8i5WE/SJZuTJGbx4I/AAAAAAAAAA0/Y8D1OJ9MzRA/s1600-h/100_3622.JPG

This is a pretty potent combo for deep fringe reception.

These Channel Master antennas look so CHEAP...

Cost cutting again...

Channel Master's new line up of antennas:

New versions of the UHF CM-42xx series of antennas:

http://www.channelmasterintl.com/documentation/datasheets/Channel%20Master%20New%204200%20Series%20HDTV%20UHF%20Antenn as_200807.pdf

Don't they look familiar (DB2, DB4, DB8)? It looks like Channel Master has sold out their souls to the devil (China). How disappointing :(

Here is their complete new line up of antennas:

http://www.channelmasterintl.com/documentation/catalogs/Channel%20Master%20Terrestrial%20Catalog_20080731.pdf

If you are looking for a Channel Master antenna, you had better snatch up their 'old line' stock of traditional antennas before they disappear, otherwise go with a Winegard product.

Channel Master's new line up of antennas:

New versions of the UHF CM-42xx series of antennas:



I wonder if they resized them to work better in the channel 14 - 52 range.

I can't help but notice that a lot of the models aren't available until the end of 2008.

I've not seen a lot of comment on this, but doesn't winter weather cause a great difficulty to an installer's ability to work on a roof or even a tower?

Could a worse time of year for our transition to have been chosen than February?

And shouldn't a company like CM have seen this coming and had their products available for a couple years ahead of time for people to have bought them and installed them before winter weather hit?

I've not seen a lot of comment on this, but doesn't winter weather cause a great difficulty to an installer's ability to work on a roof or even a tower?

Could a worse time of year for our transition to have been chosen than February?

In Texas? Yes -- July or August when the temperature on a metal roof or composite shingles can get up to 150º or higher. Working outside in February is a treat out here for installers.

You may want to attach the coax to your mask pipe, as it is causing additional stress on the antenna leads. This will break in a matter of time.

Most of the coax IS connected to the mast with two exceptions...the coax running from the 91XG to the mast (it is attached once it reaches the mast) and from the mast (where, again, it is attached) to the balun on the 306. The coax running to the 306 serves more as a sort of drip loop to keep water from constantly flowing over the balun and seeping into the coax when it rains. I'll take replacing a balun to replacing water logged coax.

Also, route the coax out the back of your 91XG.

The coax IS routed out the back of the 91XG. Not sure what picture you are looking at. It runs out the back of the 91XG through the screen (per the instructions that came with the 91XG), then back to the mast where it is attached (instead of running it straight to the 7777 and putting stress on the UHF input), then up to the CM777. The slack cable coming out the back of the 91XG is pretty much unavoidable.

Nice set-up, but cable management is POOR.

Poor? The only bit of coax that may be a little poor is the coax running from the mast to the 306. Considering it has survived a direct hit from an F0 tornado as well as a ton of southern thunder storms, I think it works pretty well. But thanks for your constructive criticism. Feel free to post pictures of your setup so we can see how it's done. :)

I wonder if they resized them to work better in the channel 14 - 52 range.

Very hard to tell, especially since the new catalog lists 2 different dimension for the CM4228. The original was 5"L X 39.5"W X 36"H, and thats what is listed in the bottom specs of the catalog for the new one.
But under the picture of it, it lists 5"L X 49"W X 32" H. So they may have, but they shortened the height ??

:confused:

ToddUGA that is a nice setup; like mine except because of a tree I couldn't get a 306 so had to go with a shorter Winegard HD5030.

Todd,

Maybe, these pictures will help explain what I mean by cable management. No cables are free to blow in the wind. Your connection is hanging in the air.

I would also move the pre-amp down the pole. (Towards the earth). It is obstructing the pick-up of the antenna.

Most of the coax IS connected to the mast with two exceptions...the coax running from the 91XG to the mast (it is attached once it reaches the mast) and from the mast (where, again, it is attached) to the balun on the 306. The coax running to the 306 serves more as a sort of drip loop to keep water from constantly flowing over the balun and seeping into the coax when it rains. I'll take replacing a balun to replacing water logged coax.

The coax IS routed out the back of the 91XG. Not sure what picture you are looking at. It runs out the back of the 91XG through the screen (per the instructions that came with the 91XG), then back to the mast where it is attached (instead of running it straight to the 7777 and putting stress on the UHF input), then up to the CM777. The slack cable coming out the back of the 91XG is pretty much unavoidable.

Poor? The only bit of coax that may be a little poor is the coax running from the mast to the 306. Considering it has survived a direct hit from an F0 tornado as well as a ton of southern thunder storms, I think it works pretty well. But thanks for your constructive criticism. Feel free to post pictures of your setup so we can see how it's done. :)

I wonder if they resized them to work better in the channel 14 - 52 range.

The brochure states channels 14-69, not 52, but the dimensions are larger (24.5" vs 20" wide) and smaller (33" vs 36" tall). It's clear the two reflectors are much wider, but they are centered on the pairs, not individual elements, so perhaps element spacing is expanded as well. Can't say a thing about wiskers ...

Frank

In addition, the brochure says the new 4228 "EXTREMEtenna" supports channels 7-69, not just 14-69. So even though they're losing the continuous screen that allows the current 4228 to pick up high-VHF, they're now explicitly claiming that their new 4228 can pick up high-VHF. They still rate it as a gain of 12.0 dB on UHF like the current 4228. I wonder if the new one is lighter, has a better feed system connecting the left and right 4-bays, and can stand up to ice and snow better than the current generation.

In addition, the brochure says the new 4228 "EXTREMEtenna" supports channels 7-69, not just 14-69. So even though they're losing the continuous screen that allows the current 4228 to pick up high-VHF, they're now explicitly claiming that their new 4228 can pick up high-VHF. They still rate it as a gain of 12.0 dB on UHF like the current 4228. I wonder if the new one is lighter, has a better feed system connecting the left and right 4-bays, and can stand up to ice and snow better than the current generation.
Another question is, have they actually done something to increase high VHF gain or are they just capitalizing on this antenna's modest ability to get some high VHF? Someone who has strong high VHF signals can probably get the 4228 as we know it to suffice, but unless they have done something rather remarkable it's not going to be a high VHF solution for anyone in the deep fringe like it can be for UHF.

Another question is, have they actually done something to increase high VHF gain or are they just capitalizing on this antenna's modest ability to get some high VHF?
Well, they increased the width by 9 1/2 inches. That should help channels 7, 8, 9 anyway.

Todd,

Maybe, these pictures will help explain what I mean by cable management. No cables are free to blow in the wind. Your connection is hanging in the air.

I would also move the pre-amp down the pole. (Towards the earth). It is obstructing the pick-up of the antenna.


Our antennas should be here tomorrow and we will be installing them Saturday. Where should the pre-amp CM7777 be installed? Should we put it between the 2 antennas or should it be below the bottom antenna (closest to the earth)? We are planning on 18-24 inches between the antennas. Any greater separation would put the lower antenna right too close to the roofline.

Shuddle

I've just been given a Antennas Direct DB8 and am going to chiminey mount it. But I can't seem to figure out how to ground it. Since I'm in a cinder block house and the RG6 drop is straight down into the roof.

I don't know if it matters but their is a lightning rod. Could it be used as a ground?

I don't know if it matters but their is a lightning rod. Could it be used as a ground?

If the lightning rod is properly grounded, sure you can. But the new code also requires a ground wire from that ground to the main electrical box.

I've just been given a Antennas Direct DB8 and am going to chiminey mount it. But I can't seem to figure out how to ground it.

Be sure to ground the antenna and the coax - not just the antenna.

Be sure to ground the antenna and the coax - not just the antenna.

hmmm...are there any how to's on that? I know for the coax they make grounding blocks that you pass it through and the ground wire attaches to it, but what about the antenna? Do I drill a hole through the antenna mast and run the ground wire through it...? :confused:

Also...if my 4-way splitter, which is inside my house and after my pre-amp/power supply, is grounded, do i still need a grounding block outside for the coax?

Sorry guys...I'm clueless about this stuff.

So I ground the antenna and mast straight to the lightning rod correct? Then where do I attach the coax ground to the house? Since the coax goes striaght down the side of the chiminey into the roof.

So I ground the antenna and mast straight to the lightning rod correct? Then where do I attach the coax ground to the house? Since the coax goes striaght down the side of the chiminey into the roof.

The antenna is connected to the mast, connect the mast to the lightning rod. For the coax, connect it to a grounding block (available at Lowes and Home Depot) and follow the directions on the package. Youll need a grounding rod for the grounding block and some #6 wire. For more information, download the Channel Master Installation Guide available at their site.

Youll need a grounding rod for the grounding block and some #6 wire. For more information, download the Channel Master Installation Guide available at their site.

If the lightning rod is close to the antenna, it's ground rod may also be close to the antenna. If so, couldn't he use the same ground rod for the coax grounding block connection? By doing it this way he wouldn't have to bond the new grounding rod to house ground - assuming the one on the lightning rod is bonded.

By doing it this way he wouldn't have to bond the new grounding rod to house ground - assuming the one on the lightning rod is bonded

You would think so. And according to the old grounding code that would be fine. But they changed the code and they have that ground running to the electrical box ground for some reason.

thanks to a almost certain visit of FAYE this next week I'll take down the 91-XG and the HD-5030 and put them in the garage. I thought about just letting the telescoping mast down as far as I can and leaving them up but to be on the safe side think I'll just store them until the storm passes. Anyway I'll miss my OTA for a few days but thats the way it goes in "hurricane land."

Hi folks:

I just recently bought a place in the Naples area and I'm looking to put up an OTA antenna for the hidef local channels. I'd really like to do it as an attic installation due to issues with the HOA and the need to make anything mounted outdoors strong enough not to become a projectile in a hurricane (appropriate timing since Fay is going to pass close by, but I just got done having hurricane shutters put on the place a few days ago, so for once I was ahead of the curve :) ).

I'm attaching the output of tvfool.com showing the signal strengths for my area. Fortunately everything is in the same direction (north), and the only ones I really need are the major networks (NBC, CBS, ABC, FOX). From what I've read I think I'd need something like the Winegard HD-1080 with a pre-amp. I was looking at that one because one of the channels is going to remain in the high end of VHF, so I was thinking that some of the others like the CM 4228 might not work well because of the VHF channel. Also, the roof is the basic Florida style tile roof, single story, and since this is in a golf community all the villas are close together so I have a neighbor about 15 to 20 feet to my direct north with an identical villa (not sure if the signal would have to go through his attic first to get into my attic since he is between me and the transmitters).

Thoughts and suggestions welcome.


Thanks,

mudtoe

Go with the CM 4228. It's a far better antenna, even for channel 9. Winegard's own specs (http://www.winegard.com/offair/antennas/hd1080.htm) on the HD-1080 show a channel 9 gain of negative 8 dB -- relatively speaking, that means rabbit ears would be roughly 8 times better. The '4228, on the other hand, has channel 9 gain of about 4 dB (see the plots for several different models under "Using a UHF antenna for VHF" here (http://www.hdtvprimer.com/ANTENNAS/comparing.html)).

The HD-1080 wouldn't be a good choice at your distance from the stations when mounted up on the roof, much less in the attic. It's too weak, even for the UHF stations. The CM 4228 is a much better choice in your situation.

If the antenna is intended to serve just one receiver, you may or may not need an antenna-mounted pre-amp. If this is the case, install the antenna first and then add an amp later if necessary. You'll probably need a pre-amp, though, if you'll be distributing signals among two or more sets.

The graphs were pretty interesting. Sounds like I need to get a 4228. With regard to the pre-amp, if I get one does it matter which end of the cable I put it on? I'm kind of thinking it does and that it should be as close to the antenna as possible, but that's just intuition on my part. Unfortunately I don't think that there are any power outlets in the attic, so that would mean installing an outlet, or running an extension cord from the garage to the attic, which I'm sure a code inspector would frown upon.

mudtoe

Your intuition is correct: A pre-amp goes as close to the antenna as possible. Fortunately, they don't require a nearby outlet. All pre-amps work with a power injector inside the house that sends direct current up the coax even as the pre-amp sends signals down the cable. The injector is placed inline near the receiver (in the case of just one) or just before the splitter (if signals are going to more than one TV).

I understand why an attic antenna is desirable for you, but they do have drawbacks. Instead of repeating everything here, please read the section on attic installations in HDTV Primer (http://www.hdtvprimer.com/ANTENNAS/glossaryA.html#attic). One thing it doesn't specifically mention is tile roofs: Since most tiles are made of concrete, they're signal killers, too.

When you have the time, please read the rest of the primer's comprehensive section on TV antennas (http://www.hdtvprimer.com/ISSUES/erecting_antenna.html). It's well worth reading, even if it does get technical at times.

and the need to make anything mounted outdoors strong enough not to become a projectile in a hurricane
See what the TVFool numbers look like with 20 or 25 ft in the air. Yes, you would want the antenna mounted strong enough so that it doesnt become a projectile in a hurricane, but thats not all that hard to do. In a hurricane, there will be a lot more other projectiles to worry about, heh.

Every 3db is a doubling of signal power. (does this rule apply to TVFool figures ?) So 127.9 minus 113.1 equals 14.8, almost 15db. So that would be 3 X 3 x 3 x 3 x 3 = about 243 times more signal. Even at -113.1dbm, you may not get that station consistantly.

3db is 2x power; 6 db is 4x power; 9 db is 8x power; 12 db is 16x power and 15 db is 32x power. That's what 'every 3db is a doubling of signal power' means.

That's only an approximation; the +10db intercepts are solid, however:

+10db means 10x power (+20db means 100x power and +30db means 1000x power).

14.8db is somewhere above 25.1x power (14db) and below 31.6x power (the 15db intercept to one decimal).

Wikipedia lists this factor as 1.9953 (every 3db is an increase in power by 1.9953):

+3db x 1.9953 (~ x2
+6db x 3.9812 (~ x4)
+9db x 7.9437 (~ x8)
+10db x 10.0000
+12db x 15.8501 (~ x16)
+15db x 31.6258 (~ x32)
+20db x 100.0000
+30db x 1000.0000.

This can be graphed (simply) to get the in-between values.

You would think so. And according to the old grounding code that would be fine. But they changed the code and they have that ground running to the electrical box ground for some reason.

Has to do with lack of equipotential grounds if it isn't done this way.

When the storm cloud passes overhead, the ground potential of the electrical service entrance goes up, and if the lightning rod (or antenna mast) ground rod isn't bonded to the service entrance ground, a large potential difference arises between the two grounds. This places the sensitive (radio receiver) equipment between two grounds at different potentials.

Because of impedance issues, two 8' ground rods should be spaced no closer than 16' apart -- it is a mistake to hammer in ground rods every 4' or 6' or .. anything less than twice the length of the ground rod.

I'm recapitulating from what I've read on a forum contributed to by lightning safety professionals; I think I've got it right but as my neighbor woman says 'don't quote me' (I just quoted her).

3db is 2x power; 6 db is 4x power; 9 db is 8x power; 12 db is 16x power and 15 db is 32x power. That's what 'every 3db is a doubling of signal power' means.

That's only an approximation; the +10db intercepts are solid, however:

+10db means 10x power (+20db means 100x power and +30db means 1000x power).

14.8db is somewhere above 25.1x power (14db) and below 31.6x power (the 15db intercept to one decimal).

Wikipedia lists this factor as 1.9953 (every 3db is an increase in power by 1.9953):

+3db x 1.9953 (~ x2
+6db x 3.9812 (~ x4)
+9db x 7.9437 (~ x8)
+10db x 10.0000
+12db x 15.8501 (~ x16)
+15db x 31.6258 (~ x32)
+20db x 100.0000
+30db x 1000.0000.

This can be graphed (simply) to get the in-between values.
Graphing it would be very old school. Instead, you can just use this equation:

ratio = 10 ^ (dB/10)

In the built-in Windows calculator, there's a button labeled "x^y" for this. For 14.8 dB:

10 ^ 1.48 = 30.2

Ron

3db is 2x power; 6 db is 4x power; 9 db is 8x power; 12 db is 16x power and 15 db is 32x power. That's what 'every 3db is a doubling of signal power' means.


That was already corrected in a now lost post a few posts down from the original. I was stuck on 3's that day, heh.

Because of impedance issues, two 8' ground rods should be spaced no closer than 16' apart -- it is a mistake to hammer in ground rods every 4' or 6' or .. anything less than twice the length of the ground rod.

Yeah, it would be silly to have them that close, when a simple wire connection will do. Do you have a link to the impedence issues ? That doesnt sound right.

Graphing it would be very old school. Instead, you can just use this equation:

ratio = 10 ^ (dB/10)

In the built-in Windows calculator, there's a button labeled "x^y" for this. For 14.8 dB:

10 ^ 1.48 = 30.2

Ron

Thanks, Ron. That gives me the last piece of this (to me) puzzle -- I couldn't figure the reverse equation to '10 log (P2/P1)' -- now I have the whole thing:

10 ^ (db/10) = (P2/P1)

10 log (P2/P1) = dB

tetonca

---- notes to self ----
What is the power ratio for 14.8 dB?

10 ^ (14.8/10) = 30.2

(14.8 dB means multiply the power by 30.2).

How many dB does a power ratio of 30.2 represent?

10 log (30.2/1) = 14.8

(multiplying the power by 30.2 is a 14.8 dB gain)

What is the logarithm of 30.2?

log (30.2) = 1.48

What does '10 log (P2/P1)' mean?

It means to take the logarithm of (P2/P1) and multiply the result by 10.

That was already corrected in a now lost post a few posts down from the original. I was stuck on 3's that day, heh.


Heh. Good thing for me; I pulled more out of the discussion than I've put into it.

Yeah, it would be silly to have them that close, when a simple wire connection will do. Do you have a link to the impedence issues ? That doesnt sound right.

Apparently I conflated two different ideas. The 16' separation comes from:


[ http://groups.yahoo.com/group/LightningProtection/ ]

"How to properly construct a ground system"
Posted by: "Ed Roberts" erobertsvava@yahoo.com
Date: Wed Jul 2, 2008 8:31 am ((PDT))

Ground rods lose effectiveness if placed closer than twice their length. Thus the typical 8' residential rods should be spaced 16' apart for the most effective use of the rods. This spacing is based on a concept called the sphere of influence.



The impedance discussion was in a post on the same group by Ron Hotchkiss:

"Grounding and Bonding for an LPS and SPDs"
Posted by: "ronh_17" ronhotchkiss@msn.com
Date: Wed Jun 18, 2008 7:43 pm ((PDT))

There is, of course, merit in having a very low ground resistance. Particularly in an LPS, low grounding impedance (notice the change from "resistance" to "impedance") may aid in the prevention of arcing due to a large difference in potential that may be developed because of a "higher" impedance connection to the earth. Poor connections or even sharp bends can present higher impedance at lightning frequencies.

When he went on about 'lightning frequencies' I had an 'aha' moment. I'd thought of lightning as a DC phenomenon, even though I've 'listened to it' countless times at radio frequencies.

Also, Jack Painter in that group talks about the equipotential issue:


"How to properly construct a ground system."
Posted by: "Oceana Radio" oceana_radio@yahoo.com
Date: Sat Jul 19, 2008 7:57 am ((PDT))

Lightning energy enters the structure on the power company system and exits via communication devices and their coaxial feed lines to an isolated grounding system. Had the system been properly bonded in accordance with codes and standards cited below [he cites them later], there would have been an equipotential condition maintained that would serve to limit such current equalizations at the expense of solid state equipment in it's path.




Yahoo Groups require cookies, and this one requires membership to read any message in it.

I don't have a link, as I get the messages via e-mail rather than via the webbed interface.

tetonca

....
I understand why an attic antenna is desirable for you, but they do have drawbacks. Instead of repeating everything here, please read the section on attic installations in HDTV Primer (http://www.hdtvprimer.com/ANTENNAS/glossaryA.html#attic). One thing it doesn't specifically mention is tile roofs: Since most tiles are made of concrete, they're signal killers, too.

When you have the time, please read the rest of the primer's comprehensive section on TV antennas (http://www.hdtvprimer.com/ISSUES/erecting_antenna.html). It's well worth reading, even if it does get technical at times.

I read the information on hdtvprimer and it was very interesting, especially the part about certain antennas having negative gain for some of the VHF channels. I think what I'm going to do is get a 4228 with a pre-amp and try it in the attic first. If that doesn't work, then I'll have to look into mounting it outside. BTW thanks for all the help and pointers. You certainly saved me a lot of leg work, and potentially having to return some stuff that wouldn't have worked.

mudtoe

mudtoe, if the antenna isn't satisfactory in the attic, the HOA cannot stop you from putting up an outside antenna; they might require a back of the house install but other than that they can't stop you, FCC regs. Just let them know what you plan to do and refer them to the 1996 communications act as it refers to antennas.

mudtoe, if the antenna isn't satisfactory in the attic, the HOA cannot stop you from putting up an outside antenna; they might require a back of the house install but other than that they can't stop you, FCC regs. Just let them know what you plan to do and refer them to the 1996 communications act as it refers to antennas.

Yea, I know that, but they can make it a pain in the backside to get it done, and they can be hard to deal with on things that they would rather not have you do, even if it's not specifically forbidden in the covenants. However, if the antenna doesn't work in the attic then I will pursue it, as I don't feel like paying for cable or satellite hidef, especially when I'm not going to be there for a good part of the year.

mudtoe

Yea, I know that, but they can make it a pain in the backside to get it done, and they can be hard to deal with on things that they would rather not have you do, even if it's not specifically forbidden in the covenants.

You don't have to ask permission, the OTARD explicitly mentions that.

I apologize if you guys are tired of questions like this.

I've currently got a 40' tower, a rotator, amplifier, and the Philips MANT901 antenna I got at Menards for $70.

I've attached the TVFool data for my house, one for "all" current signals and one for "digital only" after the switchover.

Although I get adequate reception on most channels in good weather (30-40% signal strength), I think it could be better. In bad weather, there are a few channels which I just can't get in.

The antenna is in bad shape, several of the rods are bent or have fallen off, so I believe replacing it is where to start. This is partly due to having been sitting in the garage attic for three years before we moved it to the tower two years ago, partly due to mangling caused by that move, and partly due to the windy hill we live on.

My question is, if I replace the adequate antenna with a new one of the same model, will it definitely work better than the one with the missing/bent rods? Or should I go with something else?

I hope you can help.

Of course a new antenna would work better than one that is severly damaged...Use a pre-amp at the antenna and boost your signal significantly...

Since rain has only indirect effect on TV propagation (can change refractive index),
I would suspect moisture getting into balun and/or cable downlead. Replace outdoor part of coax.

Very high loss is also typical of wet twin-lead (300-ohm) cable...replace with coax.

You should be able to get quite a few stations reliably, and all the networks with a Channel Master 4228 antenna. You will have 2 VHF stations after the transition; but they are duplicate PBS, and FOX stations. The 4228 may or may not be able to bring those 2 channels in. You should have no problem improving the 30-40% readings you are getting now with the signal levels available at your location.

Thanks for all of the suggestions and advice. Both the cm4228 and the Winegard's look good, but I need that PBS station (the digital content isn't duplicated, and I have little children), so if I'm going to switch I think I'd prefer the Winegard.

I don't really know what the antenna was like before it was damaged. The damage occurred when it was sittting up there rusting in the garage attic, and in trying to get it back out (We had to get it back out of the rafters and through a tight scuttlehole). It actually got better reception after the damage, since the damage coincided with us moving it onto the tower from the garage attic. :)

Is there any way to test the cable to see if it's damaged?

I dont know where my post went recommending the Classic Single Bowtie for UHF and the FM Dipole for VHF to a fellow wanting a compact transportable TV antenna solution.

But I just acquired this.....Ill be testing it out.

http://i302.photobucket.com/albums/nn88/EscapeVelo/IMG_0216.jpg

RS 15-1607 seems to be simple rabbit ears with a Preamp:
http://www.radioshack.com/search/manualResults.jsp?sr=1&origkw=150-1607&kw=150-1607&kwCatId=&hideBackToAll=true
Must be obsolute...not even an English manual...hope it was discounted...
A UHF loop would have much higher gain....
And modern Preamps have much lower Noise Figures....

If you are considering antennas that plug into an AC outlet,
R-S also made a WHOLE HOUSE ANTENNA:
http://support.radioshack.com/support_video/doc33/33067.htm
[Power line noise probably kills reception...but who knows....]

And you might even find an alternative use for all those beer cans:
http://diyfreetv.blogspot.com/2008/01/how-to-build-tv-antenna-from-beer-can.html:p

Thanks for all of the suggestions and advice. Both the cm4228 and the Winegard's look good, but I need that PBS station (the digital content isn't duplicated, and I have little children), so if I'm going to switch I think I'd prefer the Winegard.

I don't really know what the antenna was like before it was damaged. The damage occurred when it was sittting up there rusting in the garage attic, and in trying to get it back out (We had to get it back out of the rafters and through a tight scuttlehole). It actually got better reception after the damage, since the damage coincided with us moving it onto the tower from the garage attic. :)

Is there any way to test the cable to see if it's damaged?
Spray it with a garden hoze and see if the signal degrades????

Run a temporary coax bypass cable from antenna to TV...

n4yqt

The picture of the HD-7697 posted is not correct but one of the smaller versions.

I have two HD-7697 antennas and have pictures if anyone is interested.

Yes, the other suggestion was the Unamped Silver Sensor, which can be broken down into 3 pieces for transport and reassembled onsight.

The RCA ANT110 basic unamped Rabbit Ears & Loop would be good too, and simpler than the Bowtie + FM Dipole combo.

All 3 are good suggestions for a portable TV Antenna.

As well as th

n4yqt

Sorry, i didn't mean to come across the way you took that.

Most every web site that i looked at when got mine didn't show the actual product.

In front of the vee it has two sets of the 53" instead of one and five sets not three behind the mast.

Yes, i just wish i had tried it first not fifth.

My channel guide must be wrong. The skins on ABC and CBS tonight??

Nope its right and both in Glorious 4:3 SD. :rolleyes:

But yet NFLHD has the Redskins broadcast network presentation in HD on Sunday.

More pics of the Radio Shack 15-1607 on the Indoor Antenna thread.


What do you guys think about these antennas?

Antennas Direct V15 (http://www.antennasdirect.com/V15_vhf_antenna.html)

Includes all weather transformer
10.8 dB gain
Element width: 95"
Boom length: 43"
Weight: 6.5 lbs.

http://www.antennasdirect.com/images/v15-large.gif

Antennas Direct V10 (http://www.antennasdirect.com/V10_vhf_antenna.html)

Range: Up to 25 miles
Includes all weather transformer
7.8 dB gain
Element width: 69"
Boom length: 32"
Weight: 4.5 lbs.

http://www.antennasdirect.com/images/V10-large.gif

What do you guys think about these antennas?

Antennas Direct V15

Antennas Direct V10EV,

Never tried either of those. But for this class of small combo antennas, I would be hard pressed to believe anything could outperform the Winegard HD7210P (45.00) when "maximum selectivity" is most important.

1.Selectivity- I would have never imagined that this antenna would be capable of reliably picking up a 23kw channel 11 @ 65 miles out with 2 full power VHF-HI analogs staring right down it's throat (3 miles).

2.Sensitivity- Very respectable UHF for it's size. When compared to my 91-XG, it's definitely not as good; but it picks up all the same weak stations; but not as reliably. It performs better on UHF than the HD7082P that is now folded up in my shed.

It is a "very" directional antenna; perfect for close in areas where extreme multipath is most likely to occur.

Glen:)

Thanks, Im planning on getting a Winegard 7210p Ghost Killer to add to my arsenal.

I think Ill pass on those antennas Direct models....Channel Master and Winegard are superior quality wise in general arent they?

Here is the Winegard 7000.

http://www.summitsource.com/images/products/ANW000.jpg

http://www.winegard.com/offair/antennas/pr7000.htm



Here is the Channel Master 2001.

http://pimages.solidsignal.com/CM2001_zoom.gif



Does anybody have any experience with any of these antennas?

Anybody know where I can pick up a Winegard YA-6713?

Does anybody have any experience with any of these antennas?


I think I have that Winegard pr7000 in my collection. I need a better picture, but it looks very very similiar. Its a good local antenna.

I guess not quite, but similiar.

http://img440.imageshack.us/img440/2092/dscn0273648x486486x364wk1.jpg

Nice antenna, thanks for sharing the pic!

Anybody know where I can pick up a Winegard YA-6713?
W-G's 6-element VHF Yagi has been discontinued.
[Total of 5-elements plus a VSWR matching "stub" next to driven element.]

Antennacraft Y5-7-13 5-element VHF Yagi is equivalent:
http://www.solidsignal.com/prod_display.asp?prod=Y5-7-13
[Since it uses a folded dipole, it does not need the matching stub found on W-G's.]

===========================
Alternatively, you can use the longer, 10-element W-G YA-1713:
http://www.solidsignal.com/prod_display.asp?PROD=YA1713
http://www.summitsource.com/winegard-ya1713-yagi-tv-antenna-reception-aerial-prostar-1000-10-element-offair-vhf-broadband-ch-713-high-definition-signal-outdoor-local-cahnnel-blue-zone-part-ya1713-with-coax-cable-p-4589.html

Or the AntennaCraft (9?) 10-element Y10-7-13 VHF Yagi:
http://www.solidsignal.com/prod_display.asp?PROD=Y10-7-13&xzoom=Large#xview
http://www.starkelectronic.com/acantena.htm

Thanks hollands, you are the best.

Nice antenna, thanks for sharing the pic!

I also took detailed pics and measurements of it, in case I wanted to model it later.

I read the information on hdtvprimer and it was very interesting, especially the part about certain antennas having negative gain for some of the VHF channels. I think what I'm going to do is get a 4228 with a pre-amp and try it in the attic first. If that doesn't work, then I'll have to look into mounting it outside. BTW thanks for all the help and pointers. You certainly saved me a lot of leg work, and potentially having to return some stuff that wouldn't have worked.


HDTVPrimer updated the 4228 page. Apparently, a new version is coming:

http://www.hdtvprimer.com/ANTENNAS/cm4228.html

Late news: Channel Master is introducing a new version of the 4228. It should be available late in 2008. It looks lighter than the present version. It has no discontinuity in the screen, eliminating the wind VHF problem. It has no vertical wires in the screen, which probably eliminates the dips in the VHF gain. It will officially be a VHF/UHF antenna, specified for channels 7-69.

HDTVPrimer updated the 4228 page. Apparently, a new version is coming:

http://www.hdtvprimer.com/ANTENNAS/cm4228.html

New version of chinese junk.

Antennas Direct (Terrestrial Digital) ClearStream2 mini review and comparison with DB2 on Indoor Antenna Round Up thread.

http://i302.photobucket.com/albums/nn88/EscapeVelo/IMG_0226.jpg

Info and Questions on my situation:
TVFool reports that all the stations I am interested in are in exactly the same location, 20 miles away, and signal strengths at my location range from -48 to -70 dB. All UHF, line of sight (I am on a hill and the transmitter is on a mountain)

I have two TV's: One upstairs and one in a half-basement. A MANT510 work barely adequately on some stations in the in the basement, and was actually fairly decent when located upstairs, but with occasional digital artifacts and drop-outs. If I ran the MANT510 signal into the pre-wired cable-TV lines from upstairs to downstairs, the downstairs TV would get better, but still not perfect. The ridiclous amount of amplified gain of the MANT510 would only help when upped to maybe 10 dB max.

So I figure I needed just a little stronger antenna signal, with minimal gain and low noise.

So I bought a radio Shack 15-2160 and mounted it in my attic (thin layer asphalt shingles)

http://www.radioshack.com/product/index.jsp?productId=2103088&cp=2032057.2032187.2032189.2032205&parentPage=family

The Performance of this antenna was a slight improvement over the MANT510 on the upstairs TV, but was worthless when it had been split off to go downstairs also (through the cabnle TV line. All other branches of the cable tv line were disconnected)

So, I got a CM 7777 and mounted it close to the antenna. This actually degraded the picture upstairs, evidenced by more noise and digital drop-outs, and didn't help the downstairs much.

Question: What signal level is considered "too high" ? I know that -100 dB is considered the lowest level for reasonable reception, but I don't know where "too much" is. Imagine my signal strength is -49 dB, I get another +12 dBd from the antenna, and +26 dB from the preamp, with a -4 dB loss at the splitter, giving me about -15 dB at the upstairs TV.

Thinking I might be overloading the upstairs TV, I moved the CM7777 to a position AFTER the splitter, so the Antenna signal is unamplified through the splitter, and only the leg going to the downstairs gets the amplification.

THIS SEEMS TO BE WORKING WELL. I imagine there might be only 40-75 feet of coax between upstairs and downstairs. So I speculate that I was overloading the upstairs TV, and the +26 dB of the amp is not overloading the downstairs because of the losses of 40-75 feet of coax.

Is this making sense ? I am surprised that the reception is so sensitive to signal level such that +26 dB overloads the upstairs but is necessary for the downstairs. It makes me think there s only a range of acceptable signals that is about the same as the loss in the coax which mught be only 8 to 12 dB (a rough estimate).

Is this true ?

Thanks for any insights.

So, I got a CM 7777 and mounted it close to the antenna. This actually degraded the picture upstairs, evidenced by more noise and digital drop-outs, and didn't help the downstairs much.

Question: What signal level is considered "too high" ?Amber O'Doul,

You are right at the limit of what the "input" of the CM7777 can accept without overloading(around -50 to -60db). Moving the pre-amp furthur down the line lowered the input signal enough to alleviate the overload condition.

The CM 7777 is designed for fringe/deep fringe areas. I like the Winegard HDP-269 in higher signal strength areas; but unfortunately; it lacks an FM trap.

You are right at the limit of what the "input" of the CM7777 can accept without overloading(around -50 to -60db). Moving the pre-amp furthur down the line lowered the input signal enough to alleviate the overload condition.

The CM 7777 is designed for fringe/deep fringe areas. I like the Winegard HDP-269 in higher signal strength areas; but unfortunately; it lacks an FM trap.
What stinks about my situation is that I have ONE station that's at about -39 dBm which makes all but an HDP-269 unusable as the one close and strong signal overloads anything else. But everything else is around -102 to -108 and could benefit from the added gain of a 7777 (especially if I decided to try rotating the antenna and looking to other markets). Fortunately these weaker signals are stable and relatively strong even with an HDP-269.

Ziggy,

How much difference did the HDP-269 make with your set-up? Did you gain any stations; or just increase the reliability of what you were already getting?

Info and Questions on my situation:
TVFool reports that all the stations I am interested in are in exactly the same location, 20 miles away, and signal strengths at my location range from -48 to -70 dB. All UHF, line of sight (I am on a hill and the transmitter is on a mountain)


If you've got line of sight to nearby transmitters, chances are the CM7777 is overloading.

With that kind of signal strength, you should be able to split off the U75R to both TVs with no amplification and get all the channels. Since putting the CM7777 on the downstairs leg seems to help, I'm thinking maybe the run of coax you are using to get from the attic to downstairs is bad.

Another possibility is that having the antenna in your attic is causing issues, not just attenuation but multipath due to internal reflections. You can try moving the antenna around inside the attic, but outside would be better.

With that kind of signal strength, you should be able to split off the U75R to both TVs with no amplification and get all the channels. Since putting the CM7777 on the downstairs leg seems to help, I'm thinking maybe the run of coax you are using to get from the attic to downstairs is bad.

That has crossed my mind also. But it is difficult to rerun cables through a finished house. Standard cable-tv cable is similar to RG-59 or RG-6 isn't it ? I could find no markings on the cable.

Another possibility is that having the antenna in your attic is causing issues, not just attenuation but multipath due to internal reflections. You can try moving the antenna around inside the attic, but outside would be better.
That is my backup plan.
As I mentioned, things seem to be working well right now, but If I have any more drop outs or issues associated with rain or snow on the roof, I will just mount something on top of the roof. Once I have committed to running cables from outside, then I can just run a cable down to the basement from the oustide also.

Thanks.

Ziggy,

How much difference did the HDP-269 make with your set-up? Did you gain any stations; or just increase the reliability of what you were already getting?
I only added the preamp because I plan to split the signal three ways soon, and some of the signals were weakened enough by the splitter without a preamp that they seemed like they'd drop out frequently.

With no splitter inline and only feeding to one tuner, I really don't need any preamp.

Im thinking about doing an AM/FM Shortwave, Scanner antenna thread.

Name that antenna!

http://i4.ebayimg.com/02/i/001/07/55/a3eb_1.JPG

Name that antenna!

http://i4.ebayimg.com/02/i/001/07/55/a3eb_1.JPGAn Antennacraft D 9000 with the corner reflector removed?????????????

Name that antenna!

http://i4.ebayimg.com/02/i/001/07/55/a3eb_1.JPG

this is just a guess, but I'm thinking its a radio shack model, similar to the one I got for free, maybe not as big though. Like mine, it has the blue plastic pieces to hold the elements in place as well as the little metal bowtie at the heart of the UHF section. Only difference is this one doesnt have the reflectors and the VHF elements on it are straight out, whereas mine are at an angle.

(I'm honestly not sure the one I got for free is a RS model, but the photos on their web page for it looked so similar...blue plastic and metal bowtie...so I'm just assuming.)

Nwiser,

Good observation. Antennacraft manufactures antennas for RS. Those blue insulators and UHF elements are a dead giveaway.

Here is a classic....looks like a double folded dipole with matching reflectors.

Rockwell, Norman New Television Antenna 1949 The Saturday Evening Post, November 5, 1949 (cover) Oil on canvas 46 1/8 x 43 3/8 in. Los Angeles County Museum of Art

http://www.artchive.com/artchive/r/rockwell/rockwell_antenna.jpg

Name that antenna!

http://i4.ebayimg.com/02/i/001/07/55/a3eb_1.JPGI'd name that antenna George.

I would say its made by Channel Master. Note the distintive uhf bowtie element, only CM has that. But it looks like the corner reflector was removed or never put on.
Those blue insulators and UHF elements are a dead giveaway.
Channel Master also used to use blue insulators.


Here is a classic....looks like a double folded dipole with matching reflectors.


In the city of Dover, Del there is a house that still has one of those on the roof, heh. And its still in good shape, not bent or anything.

Here is a classic....looks like a double folded dipole with matching reflectors.

Rockwell, Norman New Television Antenna 1949 The Saturday Evening Post, November 5, 1949 (cover) Oil on canvas 46 1/8 x 43 3/8 in. Los Angeles County Museum of Art

http://www.artchive.com/artchive/r/rockwell/rockwell_antenna.jpg

cool...I've actually seen a house in my neighborhood that has an antenna similar to that. I always thought it was for receiving Radio signals more than tv though.

The big one looks like a Channel Master 3671 minus the corner reflector.

Anyone know what the short elements interspersed with the VHF elements are? Are they for FM radio?

Been reading for a couple hours and I'm lost.

I just bought an HDTV for my parents' 65th anniversary. (65!!!!!)

They have an inexpensive cable package at their apartment complex for only $9 per month.

Went thru the auto-scan with the QAM tuner....Maybe 25 total channels, but no HD.

I was thinking of also getting them a small indoor antenna so they can get some HD channels, but the TV only has one coax input.

Is there any way to use both their cable coax and antenna inputs?

Is their an indoor antenna that uses a component input?

I'm assuming it'd be a royal pain to keep switching input cables!!

Any suggestions would be appreciated!!

thnx

Is there any way to use both their cable coax and antenna inputs?



Use an A-B switch box. Then you just have to push or slide the switch. Radio Shack also sells a remote control A-B switch box.

Out of 25 channels on QAM...there are NO HD channels!? I find that really hard to believe...What stations do you get???

Out of 25 channels on QAM...there are NO HD channels!? I find that really hard to believe...What stations do you get???

They're in an apartment complex in Western NY and for $9 they get local ABC, NBC, Fox, etc.... a couple C-Spans, religious, and shopping shows, a guide, etc....ALL show as SD.

Not sure if Time Warner is just sending SD or if I have to try some other auto-scan!!??

Any ideas? thnx

You have to scan for digital channels...Sure sounds like you have the analog or standard NTSC cable channels scanned which is most likely the case...Scan for CADTV if the set labels it that way...or DTV...or QAM...The NTSC and the ATSC/QAM tuners are seperate from each other and need to be scanned seperately...

You have to scan for digital channels...Sure sounds like you have the analog or standard NTSC cable channels scanned which is most likely the case...Scan for CADTV if the set labels it that way...or DTV...or QAM...The NTSC and the ATSC/QAM tuners are seperate from each other and need to be scanned seperately...

The owner's manual clearly says that auto-scan searches for both analog and digital channels.

Either the tuner isn't picking up the digital channels or they aren't there!

(I keep reading that the cable company is required to pass along the local channels in clear QAM as long as they offer them, so I'm wondering where the problem lies!!??)

I'll try an indoor antenna shortly to see if the tuner will pick up some digital channels OTA.

What TV make/model???

Will this FM antenna work in the US?

http://www.televes.com/fotos/1201.jpg

Yes, its European.

FM broadcast band
From Wikipedia, the free encyclopedia
Jump to: navigation, search
In most of the world, the FM broadcast band, used for broadcasting FM radio stations, goes from 87.5 to 108.0 MHz. In Japan the FM broadcast band is 76–90 MHz, unlike any other country in the world. The old OIRT band in Eastern Europe was 65.8–74 MHz.

So the polarization and all that jazz is the same?

Here is a Funke website with gain and f/b ratios of different styles of FM antenna.

http://www.funke.nl/subcategorie.php?id=38

Here are some Funke VHF Hi antennas...

http://www.funke.nl/subcategorie.php?type=sub&id=47

Name that antenna!

http://i4.ebayimg.com/04/i/001/07/e3/b169_1.JPG

Here's another name-that-antenna pic. I was in San Antonio a few weeks ago and saw a mammoth antenna on top of an AT&T office building. It was several times larger than a normal combo tv antenna and I had never seen one quite like it. Maybe one of you guys might have a clue as to what type it is. The quality of the pics are not the best since they were taken at extreme zoom on a P&S camera.

http://img403.imageshack.us/my.php?image=attantennaev7.jpg

http://img184.imageshack.us/my.php?image=attantenna2am5.jpg

The owner's manual clearly says that auto-scan searches for both analog and digital channels.

Either the tuner isn't picking up the digital channels or they aren't there!

(I keep reading that the cable company is required to pass along the local channels in clear QAM as long as they offer them, so I'm wondering where the problem lies!!??)

I'll try an indoor antenna shortly to see if the tuner will pick up some digital channels OTA.

What TV make/model???

It's a Vizio VW37L.

I've seen some earlier posts regarding clear QAM reception with this company's tuners, but I've also seen more recent posts that it should work fine!!

According to your manual...the TV scans for both digital (ATSC) and analog (NTSC) channels...HOWEVER...and this is the part you probably won't like...there is NO mention of this set having a QAM tuner...Therefore the 25 channels you are getting with the cable...are nothing more than the analog NTSC channels...

Now if you were using an antenna...then BOTH analog AND digital are scanned...So I am sorry to say that your set...while very capable of receiving HD broadcasts from an antenna...is incapable of HD broadcasts from a cable source...Sorry...

According to your manual...the TV scans for both digital (ATSC) and analog (NTSC) channels...HOWEVER...and this is the part you probably won't like...there is NO mention of this set having a QAM tuner...Therefore the 25 channels you are getting with the cable...are nothing more than the analog NTSC channels...

Now if you were using an antenna...then BOTH analog AND digital are scanned...So I am sorry to say that your set...while very capable of receiving HD broadcasts from an antenna...is incapable of HD broadcasts from a cable source...Sorry...

That's not good!

Where the manual says: ".....ATSC/Clear QAM tuner, NTSC video
decoding via RF or Composite video....", isn't that a good sign??????

thnx

That's not good!

Where the manual says: ".....ATSC/Clear QAM tuner, NTSC video
decoding via RF or Composite video....", isn't that a good sign??????

thnx

What page??? QAM isn't even in the index...

This is the manual I'm looking at:

http://www.vizio.com/assets/0/92/94/120/ec160883-98e1-4998-b87b-e6a88a0ab08a.pdf

What page??? QAM isn't even in the index...

Page 68/71 in the manual I downloaded. (It's 5.1 the specifications page, under features)

So it does...I did not check the features section...

Well then it is one of 2 things...Either the QAM listing on the features page is a misprint...which is what I think it is since the acronym is not seen any other place in the manual...or the QAM is filtered out of the feed to the apartment...You need to either call Vizio and verify that there is indeed a QAM tuner...Though I really doubt it...Elimination of features is how a TV can be sold so inexpensively...OR...and I think this is the first thing to do...Call the cable co to get verification either way about their policy on QAM...unencrypted of course...

Sorry I haven't seemed to be much help to you...I still strongly question the sets ability to receive QAM though...based on your experience as well as the manual...

BTW...I als for the heck of it...looked up your model on eBay and their descriptions falled to use the acronym QAM as well but did say:
This high definition TV features a tuner that can receive conventional analog channels (NTSC), as well as the new digital channels (ATSC), including over-the-air HDTV broadcasts, where available, and unscrambled digital cable channels.

but then states:

Key Features & Benefits:

Built-in ATSC digital/NTSC analog tuner

Receives conventional analog broadcasts and digital broadcasts, including HDTV programs where available


so I can see where confusion comes from...But with the elimination of the acronym QAM...I really don't think there is one here...

Let us know what you find out...

(I keep reading that the cable company is required to pass along the local channels in clear QAM as long as they offer them, so I'm wondering where the problem lies!!??)

I'll try an indoor antenna shortly to see if the tuner will pick up some digital channels OTA.

The outdoor antenna should work if you have a good enough signal.
The Local HD channels may be on your cable system and not scrambled but because you are only subscribing to a few channals there may be a filter that removes them and the other analog channels.
John

Page 10 of the manual:
"9. DTV/TV – Connect to an antenna or digital cable (no Cable Box) for Digital TV."

Page 14:
"2. Connect the coaxial (RF) connector from your antenna or digital cable (out-of-the-wall, not from the Cable Box) to the DTV/TV CABLE/ANTENNA connector."

Page 29:
"The channel availability through cable depends upon which channels your cable operator supplies in Clear QAM; consult your cable operator for more information."

Also refer to page 29 (auto scanning) you will see that the picture shows the scan for "cable" (top right) and denotes the number of analog and digital channels found.

That would denote a QAM tuner capability by my interpretation. ;)

Pg 45, sec 3.4.2 picture of a CABLE scan shows finding both analog and DIGITAL channels.
Pg 68 Specifications lists QAM feature.

Hence it's pretty clear the Visio has QAM capability.

Note that you have to rescan for either ON-AIR or CABLE....
probably each time you switch from one to the other...

So it does...I did not check the features section...

Well then it is one of 2 things...Either the QAM listing on the features page is a misprint...which is what I think it is since the acronym is not seen any other place in the manual...or the QAM is filtered out of the feed to the apartment...You need to either call Vizio and verify that there is indeed a QAM tuner...Though I really doubt it...Elimination of features is how a TV can be sold so inexpensively...OR...and I think this is the first thing to do...Call the cable co to get verification either way about their policy on QAM...unencrypted of course...

Sorry I haven't seemed to be much help to you...I still strongly question the sets ability to receive QAM though...based on your experience as well as the manual...

BTW...I als for the heck of it...looked up your model on eBay and their descriptions falled to use the acronym QAM as well but did say:


but then states:



so I can see where confusion comes from...But with the elimination of the acronym QAM...I really don't think there is one here...

Let us know what you find out...

I really do appreciate your efforts here...you certainly have tried your best to figure this out!!

1) I emailed Vizio yesterday asking about this problem...I'll be curious to see what they say.

2) I also will post an inquiry on the AVS forum for this model TV!

3) Depending what Vizio says, I'll also contact Time Warner.

Interestingly enough, I borrowed a Terk TV-5 and after a little fiddling, received all but one of the local digital stations that I was hoping for.

Since this antenna wasn't very highly regarded in EV's Indoor Antenna Round-Up forum, I'm hoping that I might be able to get a somewhat better performing indoor antenna (if necessary) and get all the channels they really want!!!

Page 10 of the manual:
"9. DTV/TV – Connect to an antenna or digital cable (no Cable Box) for Digital TV."

Page 14:
"2. Connect the coaxial (RF) connector from your antenna or digital cable (out-of-the-wall, not from the Cable Box) to the DTV/TV CABLE/ANTENNA connector."

Page 29:
"The channel availability through cable depends upon which channels your cable operator supplies in Clear QAM; consult your cable operator for more information."

Also refer to page 29 (auto scanning) you will see that the picture shows the scan for "cable" (top right) and denotes the number of analog and digital channels found.

That would denote a QAM tuner capability by my interpretation. ;)

Boy, you'd think that their manual is pretty definitive that it should get clear QAM on my parents' cable, IF they're actually there!!!!

The Local HD channels may be on your cable system and not scrambled but because you are only subscribing to a few channals there may be a filter that removes them and the other analog channels.
John

Is that legal???????

I don't know but a nearby cable Co. did just that. The filter was pretty easy to unscrew in the service box at the cable entry to the house.
John

Some apartment/condo complexes have an umbrella cable contract for all renters where the access "fee" is included in the monthly rent/lease and some channels may be limited.

If filters are installed by the cableco, it's legal. Removal (by the renter) is illegal.

You need to discuss your desires with the landlord and cableco to determine if there are any alternatives.

So page 14 #4 states you must select DTV...Have you tried that???

Also I don't see on 29 where it says "cable" top right...I do see "Channel Scan" top right and then analog found & digital found...maybe a different page??? I am looking at the top of page 29...at the blue box to the right of 'd' that only states:
The screen will now change to show the progress of the search for Analog (NTSC) and Digital (ATSC) channels.

No 'QAM' mentioned at all...Basically I am just saying that this manual is damn confusing...Honestly I would hope that a QAM tuner exists in this set...But there is no clear cut definitive statement one way or the other...

Ratman may be correct and for the OP I hope he is...But I still feel...going solely by the manual...that whoever wrote it was/is confused because it just isn't worded correctly when "digital cable" is being referred to...which is what is leading to the confusion...Note that on pg 29 that it says:The channel availability through cable depends upon which channels your cable operator supplies in Clear QAMTo me this is what is confusing everyone...The NTSC (analog) tuner is most certainly cable ready but to know the channel availability depends on your cable operator. That is most likely...at least the way I am interpreting it...what is meant...On all the pictures of screen shots I do not see anything that would lead me to believe QAM is incorporated in the set...The ONLY reference I see is NTSC/ATSC or Analog/Digital which is the same thing...

Curious to hear what Vizio and the cable co have to say...

So page 14 #4 states you must select DTV...Have you tried that???



If you look at the Input List at the bottom of P.29, it doesn't even show DTV, just TV.

I've cycled through that input selection about 10 times today while over at my parents'.....I don't think DTV was ever an option.

But the very bottom of pg. 29 says:

a. Select the correct input connection RF (DTV/TV)

See...I don't think the manual is correct...Too many differences in words compared to actual options...

All references with the term "digital cable" aren't confusing at all IMO. Searches on the web also state QAM capability for this model #.

Also I don't see on 29 where it says "cable" top right...I do see "Channel Scan" top right and then analog found & digital found...maybe a different page???
My bad.... refer to page 45. Section 3.4.2 Auto-search

Is that legal???????Apparently. The FCC rules (which are not really law), are vary vague on the matter. The municipally owned cable system here where I live, provide no HD clear-QAM. In fact, they only provide 1 clear QAM channel, and that's the local ABC affiliates 24/7 weather sub-channel! The only way to get HD on cable here is to subscribe to their digital cable package w/HD, and pay an additional monthly fee for the HD cable box!(I keep reading that the cable company is required to pass along the local channels in clear QAM as long as they offer them, so I'm wondering where the problem lies!!??)The way I've read the FCC rules, they must carry one channel from each of the local stations in the basic tier. If that one is analog, there is no requirement to carry digital in the clear. If the one channel is digital and provides HD content, and is a part of the basic tier, then it must be provided in the clear.

However, this is where it gets vague (at least locally). My cable co. is now converting the digital signals from the locals to analog, but still no clear QAM. They still consider "basic cable" to be analog, and anything digital (including HD locals) to be premium content available only at an additional charge and requiring de-scrambling.

...looks like a Channel Master 3671 minus the corner reflector.

Anyone know what the short elements interspersed with the VHF elements are? Are they for FM radio?Those short elements are for VHF-high band (7-13). The shorter of the long elements would be for FM, which is just above the channel 6 frequency range, but still way below channel 7.

Apparently. The FCC rules (which are not really law), are vary vague on the matter.

The way I've read the FCC rules, they must carry one channel from each of the local stations in the basic tier. If that one is analog, there is no requirement to carry digital in the clear. If the one channel is digital and provides HD content, and is a part of the basic tier, then it must be provided in the clear.

However, this is where it gets vague (at least locally). My cable co. is now converting the digital signals from the locals to analog, but still no clear QAM. They still consider "basic cable" to be analog, and anything digital (including HD locals) to be premium content available only at an additional charge and requiring de-scrambling.

I've seen lots of people state that this is "the law," but I also saw where someone sighted what was supposedly the actual regulation and I didn't think it actually said clear QAM was req'd!!??

For now, I'd guess that you're absolutely (?) correct!!!

thnx

Searches on the web also state QAM capability for this model #.




I've read aw much as possible and most everything indicates this set has a QAM tuner!

I did post an inquiry in the Vizio-37 forum and am awaiting a definitive confirmation from all those folks.....

I think my problem is with Time Warner.

thnx

I think my problem is with Time Warner.

thnx

As I said earlier...I would call the cable co...Time Warner in this case...first...You can call today and probably get an answer...

I think my problem is with Time Warner.
TWC and/or licencing/pricing agreements/restrictrictions with the landlord of the housing complex.

Antennas Direct (Terrestrial Digital) ClearStream2 mini review and comparison with DB2 on Indoor Antenna Round Up thread.

http://i302.photobucket.com/albums/nn88/EscapeVelo/IMG_0226.jpg

Never seen aything like that before

It looks kinda like a clownish ancient egyptian symbol.

I've read as much as possible and most everything indicates this set has a QAM tuner!

I did post an inquiry in the Vizio-37 forum and am awaiting a definitive confirmation from all those folks.....

I think my problem is with Time Warner.

thnx

As I said earlier...I would call the cable co...Time Warner in this case...first...You can call today and probably get an answer...

OK.....Vizio confirms this is definitely a QAM tuner!

Time Warner confirms they DO NOT give any digital channels with the Lifeline package, but would be glad to provide a couple digital channels for 3 times what they now pay.

HERE'S MY Question: Tuner works fine with a Terk TV-5 that I borrowed- we get 6 local digital channels that they're interested in, but the 7th local only comes in analog.....any suggestions on what antenna might do a better job?

Am I better off posting this question in my local HD forum?

I dumped Time Warner last summer for ota and Netflik.

Am I better off posting this question in my local HD forum?
Couldn't hurt.

Hope this is the correct topic to post this question to.

I'm in an apartment and looking to improve reception on my DTV CECB. I've currently got an old RadioShack double bow-tie I found in storage that pulls in most local channels - a couple of them well, but the rest get breakups especially the NBC and ABC affiliates (and the CBS affiliate is completely gone broadcasting digital on RF 3 pre transition). I also live near train tracks and every time a train goes by the picture quality really breaks up. Windows are not positioned well to allow an antenna near them.

I'm thinking I need to replace the settop antenna anyway since a couple of the stations are moving back to VHF post transistion. I'm considering one of the Philips or RS amplified antennas (will also be reading EV's antenna test topic), but I'm unclear on the topic of amplification. Different antennas promote different DBs of amplification and I'm not sure how to determine or measure what I would need (or even if I truely need one). More seems better, but I suppose it's possible to get too much. I've atached my TVFool map. It would seem I need a -70 to -90 DBm, but I'm not sure how to translate that.

Thanks much

http://img99.imageshack.us/img99/1451/radardigital2qw6.png

Do I need an amplified indoor antenna?

No: Those trains are going to be a reception factor regardless of what you buy or do. Sorry to say it, but the only sure way to eliminate train dropouts is to move far away from the tracks the next time your lease is up.

The double bowtie is a terrific antenna for indoor use. It's been discontinued for years, and nothing on the market now is going to beat it. You can make your own antenna system that will outperform just about every indoor antenna by adding less than $30 worth of parts to the double bowtie, as follows:

If you're handy with a soldering iron (or know someone who is), remove the double bowtie's old twinlead cable and attach a balun (a transformer that can accept a coax cable) to its rivet points on the back. Attach a short RG-6 coax cable to the balun. That will eliminate interference from electrical noise and improve its performance.

As you know, the double bowtie won't get VHF signals. So, get a simple pair of VHF-only rabbit ears (two long whip antennas without a UHF loop in the middle). Cut off most of the twinlead from the rabbit ears' base, twist each of the twinlead's bare wires together with the leads on a second balun, then solder and tape over the two splices. Connect a second short RG-6 cable to the balun.

To combine the coax cables from the double bowtie and the rabbit ears, buy a UVSJ band separator/combiner. Search online for availability (RS doesn't sell them). A UVSJ is like a splitter and costs about the same, $4, but it loses far less signal than a splitter. It has dedicated inputs for the VHF and UHF antennas, and a coax "line" output for connecting it to the CECB with a third RG-6 cable. Best to keep this last cable at 6 feet or less, 9 feet max.

Parts list:

* Three RG-6 coax cables (if you don't already have them)
* Two balun/transformers
* One UVSJ
* One set, VHF rabbit ears

I had a double bowtie for years. It got beat up over time (it is pretty tippy, isn't it?) and had to be discarded. That was a sad day.