Well, have some news.
Jumped right in and played around with these critters. The antenna has a small preamp built in. You can also run these out for a ways. Extended it with shielded stereo mini-jack cable about 50ft, worked fine. And since I was integrating two B65's, ran into some other fun stuff. The office where these were at had a lot of steel, so there were dead spots at the opposite ends. If I used one antenna, and split the output between the two B65's, it worked fine in the middle areas, but could not find the sweet spot where the entireoffice was covered. Trying to fudge two antennas into the mix, however, one at each end of the office for better coverage, failed. I could get either antenna to work both B65's, but not together. It could've been from impedance mismatch, or not enough power to drive both preamps, or....? In any case, no amount of fooling around with positions would get them to work together. If Sony would give out more specs, or better still, make a little adapter to mix signals and keep power high enough for them to work..... Yeah, and I might win the lotto, too.....
Dan