Hi fellow OTA HDTVers. I'm getting a chance to doing something I have always wanted to do: put a Channel Master CM7777 preamp onto my homemade HDTV antenna that is used for viewing the Canadian channels here on Grand Island NY.

Before we start, here is a little history.. I live in an apartment complex that does not allow outside, rooftop, or attic antennas. Nothing can be permanently attached to their building. Our choices for TV are Time Warner cable, satellite (dishes are mounted on poles that are sunk into the ground), or TV-top antenna. TV top antenna reception is decent with 17 and 29 coming in good, but 2, 4, 7, and 23 can be "hit or miss" depending on antenna choice/location. Also, we're too far away from Toronto to get any of the Canadian channels using a TV top antenna. You would think our reception would be a little better for the American stations considering our TV fool chart:

[Link: tvfool.com]

The homemade antenna is a Hoverman mounted on a 2x4 that is 36" long. I prop this antenna onto a north facing window ledge (depicted in one of the photos below) and use it to watch the channel 5 Hockey Night in Canada HDTV feed and have been getting great results. I also used it to watch the Olympics on channel 9 with "mixed" results. By "mixed" I mean sometimes the channel was there, sometimes it wasn't. I guess the combination of the antenna, 20' of RG-6 cable, and the TV's RF receiver, must put me right at the "cliff" for channel 9 reception. I wanted to improve that, and also see what else can be pulled in from our brother to the north. Here are several antenna pictures in no particular order; some even with a tape measure showing antenna measurements/dimensions in case you wish to build one of these...

[Link: flickr.com]
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On to the comparison. Here is a chart showing what can be picked up from my location using the above antenna when the antenna faces Toronto with NO preamp:

5.1 - digital, 3 out of 4 bars signal strength, solid picture!
9 - analog, almost unwatchable with lots of snow
9.1 - 1 bar strength, picture comes and goes due to "cliff" effect
11.1 - 2 bars, sometime breaking up for a second or 2 but quickly comes back
13 - almost unwatchable with lots of snow
15 - watchable
17.1,.2,.3 - 3 bars
19 - strong analog signal!
25 - slight to moderate snow
25.1 - not there 95% of time, way over the cliff..
26.1,.2,.3 - 1 bar
28 - too much snow to see what's going on
29.1,.2 - 3 bars
36 - decent picture, some snow but watchable
41 - decent picture, some snow but watchable
47 - decent picture, some snow but watchable
48 - lots of snow
55 - lots of snow but can watch
61 lots of snow, can barely watch

The preamp is in transit as I create this post. Its arrival is expected in the next day or two. After it arrives, I'll connect it to the Hoverman, take data while the antenna is aimed at Toronto, and post the results on this thread. It is my sincere wish that this information proves useful to anyone that may be considering an an OTA antenna setup, whether it be home-made or professionally installed.. .

Update: The CM7777 arrived last week and I've spent the past few days testing the antenna setup with the new preamp. I can say I'm not disappointed, but I'm not completely impressed either. I have a feeling that something is "missing" with my present setup, whether it be the cheap "Made in China" hardware store balun I'm using, or the 3 foot (RG-6 I think) feed cable from the balun to the preamp. Then again, perhaps my expectations were somewhat inflated cause if I had built an antenna able to pick up 9.1 consistently I would have been jumping for joy!

In the interest of keeping this a true "apples to apples" comparison, the original setup that was used for measurements in the original post was used again for these measurements. Time of day and weather conditions were matched too. Here are the results with the CM7777 attached...

5.1 - digital, 4 out of 4 bars signal strength all the time.
9 - analog, less snow now
9.1 - fluctuates between 1 to 3 bars, 90% reliable
11.1 - 3 bars now
13 - still unwatchable with lots of snow
15 - watchable
17.1,.2,.3 - 3 bars
19 - now crystal clear, almost "digital-like" picture
25 - slight snow
25.1 - wants to come in, but still breaking up
26.1,.2,.3 - 2 bars now...
28 - very snowy but can see what's going on now
29.1,.2 - 3 bars
36 - good picture with just a little snow now
41 - now crystal clear!
47 - good picture, slight snow
48 - washed out picture, no audio
55 - snowy but watchable
61 lots of snow, can barely watch

NEW channels:
5 - very snowy, unwatchable
11 - snowy but watchable
12 - barely comes in, mostly snow
36.1 - comes and goes, 20% reliable, 1 bar when it comes in
44.1 - comes and goes, 10% reliable, signal as hi as 2 bars when it did come in
45 - very snowy but watchable
56 - mostly snow, cannot watch
57 - snowy but watchable
61 - snowy, watchable at times
64.1 comes and goes, 10% reliable, 1 bar when it does come in
69 - snowy but watchable

In closing, the preamp did "lock in" the channel I wanted to get; CFTO. Also, some new channels showed up, and reception for existing analog channels improved.

Perhaps this comparison will help you if you are considering adding a preamp to your setup. But, before you add the preamp, insure that your existing setup uses a hi-quality low-loss balun cause your preamp cannot amplify a signal that is not there!

I'm going to spend some time tweaking my setup, and if any of those tweaks cause a noticeable improvement in signal strength/reception, I'll post them here. Have a good one.. . Bill

Bill, this more or less is the result I achieved by adding a Winegard 18dB preamplifier. I found however using a lossyer balun actually helped because I was getting overloaded by the local UHF stations with my low-loss balun. I'm thinking you may be getting clobbered by locals on Grand Island too. I don't know about your set, but my LG measures signal strength only. So by adding the preamplifier I was increasing signal alright, but also increasing noise and distortion. I actually had a couple of channels with 100% signal that wouldn't raster. This was puzzling for about one day until I started tweaking. My Sony however shows both signal strength and bit error rate, but I didn't have it at the time to figure out what the problem was.

So I guess my point is do some experimentation before you declare the system optimized and don't be afraid to introduce some loss to your antenna system before the preamp.

Donny, I'm finding that out the hard way. You stated the issue perfectly..

Been spending the past couple days looking around for old baluns that can be used for this experiment. I'm having fun but my wife thinks I'm nuts...