OTA Intermittent Signal Fade

[LSUCheer]

I am a VOOM subscriber in New Orleans. I love the programming, but am nearly ready to go back to D* because of con-men installers and Motorola box failures. I have two HD sets and am on my 7th box.

That being said, I want to focus on one chronic OTA reception problem. I get most of the OTA channels with the VOOM's Channel Master 3000a but not the NBC affiliate. I removed the CM 3000a and hooked up my old Radio Shack, 120" antenna w/rotor. After an hour of searching I found the "sweet spot" using the rotor and got a strong 80+ signal. But, about every 30 seconds the signal drops into the teens and the picture freezes for about 1-3 seconds. Then the signal jumps back into the 80's and the picture returns. This cycle repeats every 30 seconds or so. Can anyone offer the possible reason for this and, maybe an approach to solving the problem? This is not a weather problem. The transmitter is about 10 miles away with no visible obstructions.

 

[Cougar]

If I understand your post correctly you are saying that a local channels video is freezing every 30 seconds on your TV. If that is so then your problem would be in the TV set I would think. Do you use the TV's tuner to receive this signal?

 

[mchomicz]

Can anyone offer the possible reason for this

This is known as the "cliff effect" and is most of the time caused by multipath interference. You can try to put your antenna in a different spot but other than that - there is not a whole lot you can do about it other than buy a "fifth generation" OTA HDTV receiver. I think LG makes a 5-th generation chip and it can be found in Zenith product as well as a Samsung OTA receiver.5-th generation OTA HD receivers apparently take a different approach to overcoming multipath – that is claimed by experts (not just the manufacturers) to actually work.

Hope this helps,
Michael