Finally - Some success with CM4228, CM7777

bhelms

Retired & lovin' it!
Original poster
Lifetime Supporter
Feb 26, 2006
7,801
863
Central PA
Howdy, all! I haven't had an opportunity to play around with my new equipment until this past weekend, hence the long period between my questions last spring and this report...

Some background - I have been able to receive PBS digital subchannels (WPSU - 15.1, .2, .3, .4) very well from about 35 miles away and 335 deg. bearing on my old RS VU160 antenna / Blonder-Tongue preamp, ever since I first connected the HD equipment. The HD subchannel looks GREAT and I use it as my HD benchmark. The SD subchannels are really bad. I'm glad they're prioritizing the HD channel, tho'! (The analog Ch 3 feed that is the same content as 15.2 is excellent on the TV and 811, and the same as the LiL Ch 3 from E*.)

But several co-located digital channels (24.1, 24.2 - both ABC, 24.3 - FOX, 32.2 - CBS) from about 25 miles away and 247 deg. bearing were very elusive! I once received them with the old antenna long enough in Feb. to scan them in on both my Sony and my 811. Then they disappeared again. I was never able to scan any of them with my 622. I could receive Ch 23 analog (same location) well enough on the TV to get the right bearing for the VU160 and I marked it. But the digital channels on almost the same frequency were not strong enough (or something) to even appear on the "meters". The issue is the ridge between my location and the transmitters, but surprisingly that same general condition exists with my PBS station that has always come in well. Multipath might be a problem - the analog channel is rather "ghosty" and variable with antenna bearing.

So I thought the best UHF antenna and a good low-noise preamp should do the trick. I started with just the CM4228 and some new coax (not sure of the quality) with all new compression fittings, and it made no difference. I had it mounted on the same mast as my old CB antenna, just below the radials which put it about 5' off my roof. I then added the CM7777 preamp, and again no change. I thought moving and/or raising the antenna would be the answer, but that was a bigger project than I could commit to until last Sat.

I had an old telescoping mast that is about 23' long. I added another 10' mast from RS to that and mounted the 4228 and preamp to the tip, and raised it temporarily between my other antennas. Voila! I can now receive 24.1, 24.2, 24.3 and the PBS subchannels on this set-up well enough to consistently lock them! The meter in the TV indicates 60/100 most of the time. Both the TV and the 622 were able to lock them and I get almost no drop-outs or pixelation on either (the TV is still slightly better). Boy did the Sat. college games on ABC look great in HD !! Now I need to determine what it will take to get 32.2 (CBS) from the same location. They might be at lower power presently.

Maybe someday I can luck out with this rig and also receive NBC on essentially the same bearing. Unfortunately it's about 30 miles further away, about 55 mi. total, so I don't have much hope for that channel.

NOTE: This is just a TEMPORARY set-up. I still need to ground it, weather-proof all the connections, secure the coax, and reinforce the mast with guy wires, all of which I hope to complete this weekend. I might eventually add a rotator as well. I don't think any of my channels will remain on VHF after the conversion date, so eventually those old V/U antennas will come down.

Interesting experiment - I am concerned about how that antenna/mast will survive without guy wires, not that I intend to leave things that way for long. On Sun. it was a rather windy day with gusts to 15mph. The 4228 was moving in that breeze, but not a whole lot worse than the CB antenna!

Small steps to the final goal! I can now recommend the 4228/7777 combination!
 

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Are local channels in HDTV?

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