Hey, thanks for the response, didn't think anyone read this thread anymore. The feed from antenna to Roamio is probably about 80 ft. I do have a signal without the preamp, but it is better with it (I think, if you think it helps, I'll go up and disconnect it, just in case). The screen behind the 8 bay IS attached, I assume that increases the directional strength. . .actually I get almost equal signal strength between LA and SD channels where I am. The last heavy storm we had in Jan, the antenna blew due north, and I had pretty good reception of all LA locals. I am a bit surprised that I can't get stronger signals from ABC/CBS, as Mt. Soledad is not that far. I'm wondering if changing the RCA preamp might help. The UHF and VHF have a combiner, with an FM filter attached.
Either way, I appreciate your time and response ;-)