I have tested my MB1 using my Trimble Thunderbolt external frequency reference as well as WWV. My radio is off frequency by +20 hz at 10 Mhz. The software allows you to adjust the frequency coefficient. The value I needed was as follows: -.000203 (this value divided by 100 is the frequency error) This value gets rid of the +20 hz error and achieves accuracy. Recently I decided to use my external gpso disciplined frequency reference which is Trimble Thunderbolt. I wanted to use this until my Leo Bodnar gpso I just ordered is received. The problem I am having is with the external reference connected and the MB1 external reference enabled in the software the radio still is off by +20 hz. There is no frequency offset adjustment or frequency coefficient to correct the +20 hz error with external reference selected. This is puzzling to me. For an additional test I decided to generate a 12 dbm signal (2.5 vpp) at a frequency of 9,999,980 hz using my Hp communications service monitor. I connected this signal to the MB1 external reference input radio and the radio was indeed right on frequency. I really don't want to program the Leo Bodnar unit for 9,999,980 hz to lock the radio on frequency. The problem with doing that is you can no longer use a distribution amplifier with the Leo Bodnar unit to apply the 10 MHz time reference signal to other devices.
. Does anyone know if I have missed something and there actually is a frequency offset or coefficient adjustment when using a external reference? Thanks Roger AA1LY