[time-nuts] Z3801A OCXO manual trimming
holrum at hotmail.com
Tue Mar 6 01:24:01 EST 2018
I'm not sure what the Z3801A uses for EFC range. Heather uses the EFC relative command to report the EFC setting. That command reports values from -100% to 100%. There is a command that reports the DAC input in counts, but nothing documented that shows volts/count.
Since the DAC is at -2V with a 99+% DAC setting, it looks like the DAC circuit has issues, or power supply problems. I think the DAC circuit is a 16 bit DAC with 4 more bits of resolution created by dithering the DAC inputs.
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