OK. I found it: page 34 of operating manual. Looks like the jumper at IF1 was never set correctly. Should be B or C, but was set at A. So, although I'll probably never use the FSK feature of the TS-820S, does anyone know what shift-width is common now-a-days? I suspect it would be 170 Hz, but what do I know? :-) Ken W7EKB