50 Hz? I've never heard of that with the K2. I hate to suggest the obvious, but do you have RIT enabled? Ron AC7AC -----Original Message----- Has anybody had this happen? My K2100, no. 2613, which has the KSB2 installed transmits 50Hz lower than it receives. I did the PLL\BFO stability mod, but I think this rig has done this since the very beginning... Help! Merlin Petroff, W3ICT