Hi, My Argo V (with TCXO) reads 100 Hz low, i.e. 10 MHz WWV zero-beats at a reading of 9999.900. It isn't a warm-up drift problem as the reading is quite stable with time, well within the spec of 3 ppm drift. Performing a master reset per the manual had no effect on the problem. Has anyone else encountered something like this? 73, Ray W2RS