I know many people aren't interested in data, and I'm pretty sure there's no receivable audio here, but the fcc recently froze all channel 51 applications. I use a screenreader, so if this is offtopic, I'm sorry. I couldn't find any forum relating to broadcast media. Acording to the article I read, the wireless telecommunications industry asked the fcc to freeze them because they were worried about interference. I've never heard of or read about anything in that band. I know hospital telemetry uses 608 to 614, but that's the closest thing I know of except for 700 mhz public safety systems. Might some of these systems have input frequencies in the 690's? I haven't read the 700mhz frequencies.