Meanwhile some progress made
My Trimble GPSDO 10MHz output 30mV tt amplified a filter followed by 3 stage amplifier
then shaped by hex inverting Schmitt trigger 74AC14
a reasonable clean signal at 1296.210
Shielding and grounding and a clean 5V power are important
the AM 350Hz hum side-bands are weaker
-60 dB at 144.550 -40dB 1296.210
The ADF4351 REF in seems to be a straight TTL input without analog interfacing.
It omits a trigger circuit. I had to make that myself.
The specs only give the maximum signal level for this REF nothing about the shape or minimum
usable level.
It does not work with a relative weak or sinus shape 10MHz signal.
Some other types PLL chips seem to have no issue with the reference level.
2V / division .5 uSec /devision 10MHz signal at the ADF REF input
test setup
10dB / dev.
discrete 10MHz booster 3 stage and a band filter after a lot of modifications this one can amplify the 30mV 10MHz Trimble out to 5V tt square wave derived from …
My Trimble GPSDO 10MHz output 30mV tt amplified a filter followed by 3 stage amplifier
then shaped by hex inverting Schmitt trigger 74AC14
a reasonable clean signal at 1296.210
Shielding and grounding and a clean 5V power are important
the AM 350Hz hum side-bands are weaker
-60 dB at 144.550 -40dB 1296.210
The ADF4351 REF in seems to be a straight TTL input without analog interfacing.
It omits a trigger circuit. I had to make that myself.
The specs only give the maximum signal level for this REF nothing about the shape or minimum
usable level.
It does not work with a relative weak or sinus shape 10MHz signal.
Some other types PLL chips seem to have no issue with the reference level.
2V / division .5 uSec /devision 10MHz signal at the ADF REF input
test setup
10dB / dev.
discrete 10MHz booster 3 stage and a band filter after a lot of modifications this one can amplify the 30mV 10MHz Trimble out to 5V tt square wave derived from …