Quote:
Originally Posted by rabbit73
Interference can be radiated or conducted by the power line or both. The shielding in the attic would help to reduce the radiated interference, but it might be coming in to the TV over the power line.
Is the coax grounded with a grounding block that is connected to the house electrical system ground?
It is often necessary to block the interference at the device causing the interference with an AC line filter if it is being conducted over the power line.
Interference problems can be difficult to solve, especially if channel 39 is weak.
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Thanks Rabbit...
All grounding is proper. Mast (via its own copper line) and coax (via grounding block) are grounded to a 6' grounding rod. That grounding rod is bonded to the house electrical system ground.
It is always possible that the interference is conducted via the power line, however, a few years ago I installed LED lights in that bathroom's ceiling cans (directly below the antenna), and suddenly I would lose a couple of channels (39 included) whenever those lights were on. I moved those LED lights from that location to another place in the house, and problem solved. Because of this, I suspect the LED bulbs and the hairdryer cause radiated interference, being so physically close to the antenna.
Channel 39 is in fact my weakest channel, so it doesn't take much to lose a tunable signal. If I have this correct, Channel 39 is 623 Hz which has a 480 km wavelength, meaning chicken wire should be able to block that frequency. However, I'm trying to block whatever frequency the hairdryer is transmitting.
Again, this whole exercise is completely academic as I am primarily interested in understanding the mechanics of the problem. If we can solve it in the process, that would be a bonus!