10MHz GPSDO by "BH3SAP"

[KungFuJosh]

You definitely have a different firmware, I don't recall that setting existing in mine.

[flash2b]

The PPb / PWM menu starts after powering up with a connected antenna after PPS on the  ATGM 336H-5N-31 starts blinking in Red (1Hz). This means the unit receives GPS/Beidu information from the satellites. This may take some time and the antenna position must be ok to receive signal but for my unit it starts very quickly.

If no satellites found, the unit stays on the "10.00Mhz / GPSDO" main screen.

The PWM adjusts the 1 unit PWM = 0,000076 V adjustment voltage to the OCXO. Saving needs to be done so that the next time the unit starts it goes more quickly to 10MHz output.

[KungFuJosh]

I saw the PWM screen. I never paid attention to it after startup, and never saw a PPB value. Oh well, too late now.

[flash2b]

I see you're a big fan of lab instruments, -I have been using them for 30 years 

Well you did not spend much on you FNIRSI 1014D for the PPS measurement which is also a "toy" compared to a real oscilloscope, while the topic starter had a Siglent SDS2504X HD.