Our lab has GPS disciplined rubidium freqency standard (Datum 9390-6000) and two free running rubidium frequency standards with 1pps synch options. One of those free running standards is Stanford Research PRS10 and another FS725. My main goal is to check annually the PRS10 and FS725 conditions, that they meet accuracy spesification +/-5E-11 per day. I have also posibility to use Keysight 53230A frequency counter for this evaluation. Can someone explain me what is most straigh forward method to do frequency spesification evalution for PRS10 and FS725 10MHz outputs?