Thanks so much guys for your input and jogging my thought processes!
Yes, I'm familiar with the Antenna Boost......and now, as I think about it, thats EXACTLY what the bedroom TV signal looks like with boost "off" and house cable selected.....(well, maybe not THAT bad) Hmmm? The bedroom TV is not getting the "switched" signal back to cable!
....or theres another boost switch hidden someplace.....or theres an un-terminated exterior connection. Naw, I would have found it by now. Next step, I'll remove the main terminal panel (spooky) and do a better inspection of all the connectors. Hopefully Monaco labeled the cables
After that, Bullydogs, ..........I'll do your "last ditch" effort
Much appreciated guys
Uh oh :(........I just remembered, I already did pull the boost plate off and checked those connections :( I'll do it again and swap the cables..........see if the "Main" TV goes bad. That might tell me something.
cheers