Very Interesting thread about IF-AGC and Sony HD-TVs:
http://www.avsforum.com/avs-vb/showthread.php?t=1110510
If I am to believe this channel 2.1 has a signal but there is nothing I know of there.
Could this be FM station noise I see on 2.1?
Would pre-amp be better than amp at the TV set?
What about filters to put on the antenna line?