What causes the "herringbone" interference on my TV. Any solutions?

Question

I installed a D12 directv receiver today. The picture quality by using composite and S-video output is very good with no signs of interference but the output through the coaxial cable to channel 3 or 4 produces moderate to severe "herringbone interference". I do use the s-video output to view movies but I feed the coaxial cable to the VCR for recording. I have already discounted the VCR as a suspect and I am using monster coax cable. Thanks

Answer 1

LOOSE connector somewhere....

Now, you can remove your VCR and hook the TV DIRECTLY to your Direct TV box....HERRINGBONE? Then try another RF cable first....If it disappeared without the VCR connected, you then KNOW the VCR is the source of the Herringbone pattern, and I'd replace the VCR's electronic switch for the RF signal.....

Still there on the TV? Then hook up the TV and change channels, then change it back to channel 3 with the sat connected and powered up...did it disappear? Then you just needed the tuner to track and LOCK the signal again....

Still have the Herringbone on the TV? THEN it's time to have a TV Tech look at it.....you could have a bad SAW filter, or bad AFT adjustment/alignment....or bad tuner.

Answer 2

typically caused by an interfering signal on an adjacent channel.
Maybe your VCR is putting out a signal on its coax out.
try switching it's channel and/or terminating that output with a 50 ohm terminator.
make sure all chassis are grounded together.
are you amplifying the signal? that can raise the level of the signal to cause the problem.