On Wed, 24 Nov 2010 22:34:35 -0700 "Vitaliy" wrote: > Given the number of responses and not a single "hit", I shall assume that= a=20 > 9600 baud pure-FSK modem IC does not exist. :) I've never seen FSK at 9k6, but if it really has to be that, and it has to be baseband, I guess the old VCO/PLL pair could do the job (2 ICs though, _and_ analog) IIRC XR2206 and XR2211 or so. But I'd rather sacrifice the FSK, and go to some of those PSK systems Russell indicated. John --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .