Advice for Improved Reception

[Dick]

I'm located in Lake Neepaulin near the Sussex, NJ airport and watch New York City stations. Before the digital transition, I had acceptable reception with an attic antenna, although results seemed to worsen over the years (9/11?). After the transition, to see if I would get any signal at all before investing time and money, I temporarily mounted the same antenna (with converter) on the roof and got a few New York stations. In September I installed a permanent eave mount with this same antenna. I'm able to receive channels 2,4,5,9,11,13,31,41 and 68. Reception varies with the weather, but is acceptable on most channels most of the time. Traffic at the airport is infrequent and isn't a factor. I estimate that in general there is some pixilation/interruption about 10-15% of the time except for channel 7 which on rare occasions appears, but is not watchable and has no sound.

Here is a list of what I have installed:

1. Antenna – Radio Shack, Model? – Bought 17-18 years ago but in
excellent condition as it was in the attic.

2. Mast mounted amplifier – Antenna Craft Permacolor Model 10G212

3. Downlead – RG-6, RCA, 35 feet

4. Grounding Block – Radio Shack

5. Converter – Insignia, Model NS-DXA1

6. TV – Sony, Model KV27V36

I’m also attaching pictures of the antenna, view from the antenna facing ~147° (NYC), and typical signal strength as shown by converter. When I installed the antenna there was about 50% foliage on the trees.

I'm would like to know in what order to try improvements. Easiest would be a different amplifier. Specs for the one that I have list a 50-890MHz frequency response and 30db gain. Would the CM 7777 do better?

Another option may be to gang another antenna. What would be recommended, do they have to be the same, how far apart and which should be on top?

A neighbor a few miles away recommended a CM 4228, but I’m not sure how good this is for VHF and since it measures 35 or 40" vertically, it might preclude the option of ganging a separate VHF antenna.

Lastly would be an entirely new UHF-VHF antenna(or maybe go back to radio). It would have been nice if all stations switched to UHF so that only one type of antenna is needed.

The problem with the digital conversion was that if one didn’t already have an antenna that picked up some sort of signal, you couldn’t know if investing in a more elaborate/expensive set-up would help or not. Also, as far as the coupon program went, if you bought a converter and then found out that you couldn’t get reception I understand that they weren’t returnable. I'll certainly appreciate any advice and/or recommendations that you have. Thanks, Richard Aaron

[mtownsend]

Hello and welcome!

Before getting into specifics, could you please post a link to a tvfool report for your exact location? This will let us know how strong/weak the signals are at your house.

Since your area is rather hilly, it's important to get an accurate simulation. Address lookups are not always very accurate, so I suggest you start with the Interactive Maps feature (starting point is here). This lets you see the results on a map. You can zoom in, switch to satellite view, and move the marker to fine-tune your location. Once you get the marker right on your house, you can press the "Make Radar Plot" button to generate a report using the current settings. Cut and paste the address of that report back here.

[mtownsend]

Originally Posted by Dick

Antenna – Radio Shack, Model?

Just FYI, that's a picture of a Radio Shack VU-90 XR.

[Dick]

Thanks for the reply. Here are the coordinates of the antenna; height is approximately 25 feet above ground. I must say that digital picture is excellent. Thanks

41.216043,-74.629097

[Dick]

Sorry, I forgot to include the report address in my reply. We had a little snow here today (not electronic type) and I'm just getting back up to speed.


http://www.tvfool.com/?option=com_wr...27ee97609e5c97

[mtownsend]

Originally Posted by Dick

1. Antenna – Radio Shack, Model? – Bought 17-18 years ago but in excellent condition as it was in the attic.

The VU-90 XR is an OK antenna. It's a relatively small full band antenna that does what it's supposed to. You are getting most of the channels that are within range of your location, but the problem is that it's not stable 100% of the time. This means that you could do better with some more signal margin to keep you off that "digital cliff". More margin will give you more room for variability caused by wind, trees, and weather that inevitably occur.

One way to get that extra margin is, of course, to get a bigger antenna. An antenna like the Winegard HD7084P or HD8200U will get you significantly more gain across the board and should give you much better stability on all your channels.

2. Mast mounted amplifier – Antenna Craft Permacolor Model 10G212

This amp has a Noise Figure pushing 3.5 to 4.0 dB, which is not quite as good as the 3.0 dB or less that you can get from the competition. The Antennacraft model 10G202 has better Noise Figure specs, and so do comparable offerings from Winegard and Channel Master.

However, switching to a better amp will only give you about a 1 dB improvement. This means that yes, it's possible to do better, but the gain is not very significant. I would recommend that you try a better antenna first. A big antenna will probably give you a ~5 dB improvement on most channels, and this will probably give you the added stability you need. If you still think you need that the extra 1 dB of improvement with a different amp, then you can always add it later.

3. Downlead – RG-6, RCA, 35 feet

That's good. The only word of caution I would add is that you need to make sure that all exposed connections are protected from the elements. You want to make sure that all moisture stays out of the cable and connectors because it doesn't take that much water to kill all your signals.

I'm would like to know in what order to try improvements. Easiest would be a different amplifier. Specs for the one that I have list a 50-890MHz frequency response and 30db gain. Would the CM 7777 do better?

It's my opinion that you'll get much more bang for the buck by getting a bigger antenna. The choice is up to you, but the Antennacraft amp that you have now is not that much worse than the CM 7777 or any other common amp. There are some more expensive very low Noise Figure amps (closer to 1.0 dB) that would give you a net improvement of about 3 dB, but that's still not as good as the gains you'd get from a good antenna.

Another option may be to gang another antenna. What would be recommended, do they have to be the same, how far apart and which should be on top?

If you gang antennas, you can almost gain 3 dB for every doubling of antennas. In all cases, you should only attempt this with identical antennas. Given the fact that you're starting with a VU-90 XR, you can gain a lot more than 3 dB from just a single antenna replacement.

I usually don't recommend resorting to multi-antenna arrays unless there are no other options. To do so requires learning a lot about constructing the mounts, connecting the phasing lines, and a whole slew of problems related to tuning everything.

A neighbor a few miles away recommended a CM 4228, but I’m not sure how good this is for VHF and since it measures 35 or 40" vertically, it might preclude the option of ganging a separate VHF antenna.

You are right to suspect the VHF performance of the 4228. It's VHF performance is actually lousy. Many people try to get away with a UHF-only antenna if they only have one or two really strong VHF stations to deal with, but I'd rather get the right antenna for the job. It's kinda out of the question for your situation anyway because your VHF stations are too weak to even have a chance with the 4228.

[Dick]

Thank you for the advice. I'm planning to wait until warm weather before implementing any changes as, of course, it's easier to work outdoors and to see the effect of full leaf coverage on the trees. I have a gable mount and one of the problems is that since the roof angle is somewhat shallow, the bottom brace is longish and not as rigid as I would like. Also, the ground below is sloping and without a suitable ladder I'm only able to work from the roof and can't reach the center of the lower brace to secure it better. Can you reccomend one or two antennas a little smaller and/or lighter than those that you mentioned in case I'm unable to stiffen the mount? By the way, during this weeks snow storm reception was excellent; I was even able to recieve the troublesome Channel 7!

[mtownsend]

Originally Posted by Dick

I have a gable mount and one of the problems is that since the roof angle is somewhat shallow, the bottom brace is longish and not as rigid as I would like.

You might also consider using a wall mount. That puts the mounting holes closer to the mast location and improves the stability of the setup.

If you have a suitable chimney, there are chimney straps that work well too.

One other thing to consider is to double-up on mounting hardware. With some kinds of mounts, its possible to use two sets of mounting hardware at the same time to get a really solid grip on the mast and distribute the stress over more mounting area.

Design and build quality of mounting hardware can vary from one brand to the next too (stainless steel vs aluminum, size/gauge of components, overall rigidity, etc.), so it helps to compare multiple options.

Can you reccomend one or two antennas a little smaller and/or lighter than those that you mentioned in case I'm unable to stiffen the mount?

The reason for the large antenna recommendations was because almost all of your channels are in the "red" zone and pretty weak. Smaller antennas might get you some channels, but the gamble is that you won't get channels further down the list or that the signals will be marginal (occasional pixellation and drop-outs).

The Winegard HD7084P does comes in smaller versions within the same family of antennas, but I think that going smaller is a bad idea. I hope you can find a way to strengthen your mount because it's the better way to go.

[Dick]

I do plan to stiffen the mount, but wanted to get away as easily as possible until I knew that I had some chance of recieving acceptable signals. I tried to find specifications for the VU-90R that I have now so that I could make comparisions to other antennas. I had no luck and wonder if you would know any gain figures, weight and boom length (80" I think) or where I might find the info? Again, I appreciate your sharing of time and knowledge.

Dick

[mtownsend]

Here's a lingering web page on Radio Shack's site that still shows the technical specs for the VU-90XR:

http://support.radioshack.com/suppor...oc31/31760.htm