Channel offset is something people don't understand and you cannot explain it so they will understand.


Best to just say Channel __ is just too far away for you to receive. Unless, of course, you decide you want to lose it....

Hi guys,

Used to be here all the time years ago and good to see most of you guys are still here sharing and helping. Had some cardiac problems a few years ago so I stepped away and let my son take over the business. But my company has been in business for over 40 years in the Washington DC area. We started installing TV antennas in 1978 and we have installed over 50,000 antennas.

So, if you want my two cents of advice about installing antennas.

First, you need a digital RF signal meter. Sadelco was the best but they went out of business years ago. You can still get them serviced and new batteries from a former tech. Look on Ebay for them. With a Display Max you can read digital signal levels for every OTA channel.

Second, once you get your meter you will be able to find the best spot for the antenna and direction to point it in. The location is critical because you dont want to put the antenna in a dead spot for one of your channels. I have seen countless times that moving an antenna 6' on the roof can sometimes double the signal strength for a particular channel. Don't believe me? What do you do when your phone doesn't work. You walk around looking at the display until you see your signal go up. Once you find the best spot mount it right there with a DS-3000 J pipe mount.

Third, we use Winegard antennas. 95% of our jobs we use the HD-7694. It is a VHF/UHF antenna and it is not very big but it really gets the job done. If you need more signal then put a preamp below the antenna and if that doesn't work then raise the antenna with a 10' mast and a tripod at the peak of the roof.

Fourth, if you are going to buy an RF meter and go to someones house with a ladder make sure you charge enough money. We charge $549 for the antenna to one hookup. Add a preamp and it goes up 122.00. Even with those prices people are happy because that antenna will be up there for over 25 years and save at least a thousand dollars a year to the customer.

Also, because we installed the antenna we have people who call us to install TVs,
AV systems, connect networks. So this is a way to expand your customer base.

The big question is whether you are comfortable going up on roofs but if you are doing TV antenna work can be a quick way to make money, get new customers and expand your business.

Ernie, is an old antenna guy like me so maybe he can add to some of the things that I said.

Dave T.

This is the only thing I want to comment on. Many TV signal markets do not have any stations in the upper band VHF channel range (channel frequencies 2 - 13). If any VHF channels must be received, the antenna has to be larger than a UHF-only antenna. And which you need is not determined by your equipment, but by the frequencies of the stations in your area.


Just the above, and
When our store started to carry TVs, I went to the owner and told him that we'd had pretty good luck with antenna systems just for FM (the 20 MHz just above TV channel 6), but now that we were getting into TV, we'd either have to be stupidly lucky or we'd buy a signal meter so we would KNOW what signals we were dealing with. He told me to get a signal meter.

If you don't have a signal meter, you're going to have to depend on magic or dumb luck.

So,

It would appear that the problem I have has to do with the off air tuner in the DTV HR20 receiver.

If I bypass the DTV receiver and go direct to the TV, from the antenna, the TV shows 100% signal strength and the signal is rock solid.

If I route the antenna to the DTV receiver I get constant drop outs, pixelation etc etc.


Finding this brings up a small issue in how the house is wired, but that'll just involve pulling a few new wires to get where I want this thing to be.

Just a minute: There is no off air tuner in the HR20. You can buy yourself an AM20 (IIRC), which is a TV tuner fed by a TV antenna, with its output going to a DTV receiver; its channels are integrated with the channels from the dish.

So that tells me you have a cable that is ONLY for TV signal and is not in any way connected to the dish.

That's amazing. You shouldn't be getting anything.

Wires to that area should be one or two wires to the DTV box from a multiswitch or SwM device, and a cable from the TV antenna to that TV.

I don't know how you can be SO wrong.

Look at the pic of the rear:

[Link: ebay.com]

Notice that RF connector that has a "Off-Air in" label?


That said I have ONE COAX to the DTV receiver satellite in from a SWM dish, and ONE COAX from the Channel Master OMNI+50 antenna.


As I said, when I have that ONE COAX routed into the DTV receiver I lose signals. Some entirely and some sporadically. When that ONE COAX is run directly to the TV, I get 100% signal and no issues at all.



Now when I say some new wiring, I mean from the antenna to a RF distribution amp, and some runs out to the other TV's as I am in the process of eliminating DTV. I guess that helped confuse?

It's easy: Unbridled enthusiasm coupled with a large bowl full of assumptions. I have never actually seen this model.

Yes. Lookee there!

Yeah, well, now I AM confused. You're getting TV signals when you connect the OTA antenna to the HR20's TV IN connector. And you're getting rid of DTV. Why are we talking about DirecTV signal problems at all?

Dropping DTV is sort of a slow process as I wait for a Tivo and a HDMI to component adapter to show up, and I thought this was an interesting tidbit.

Apparently the off air tuners that DTV sold were pretty lame in that they required am overly strong signal as compared to a TV tuner?

If I install a pre-amp at the antenna the signal is TOO strong, so I lose channels on the TV and gain some but also lose some on the HR20.

It's sort of a WTH thing that I found interesting. Sort of an old school science project...:-)

We still do OTA it's still very popular. A good meter is a must and if you know your area it's good. Sometimes we use a large antenna with rotor (all rotors suck these days...), sometimes just one antenna, sometimes 2 with a combiner. Have not done big jobs for a hotel or anything in years, most basic home installs are a snap.

I got to know my area when I was in charge of all electronics for a 10-store chain of A/V stores, using a $600 analog meter by Leader. That was the mid 80s. Experience is how you used to have to learn.

Near the end of that job, I discovered that (the Los Angeles) TV stations had coverage maps that could tell you what signal to expect within about 1/4 mile of where you are.

Then antennaweb.org and tvfool.exe gave detailed direction arrows overlaid on a map. This was the most accurate way to aim.

All of this experience and technology didn't predict or solve multipath, though. You had to be able to imagine where signal reflections might come from in order to avoid them.