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Have been testing the ADF4351 demo board some time now

But the signal from the PLL  is very IMD distorted and unstable
Useless  sofar ...

Arduino Uno  controling ADF4351A      F1CJN sketch

QRPLABS   Progrock / SI5351    and  GPS QLG1 receiver

all locked
the Progrock output 10MHz ttl level signal  matches the ADF REF input good

output  1296.200    T9 + huge IMD  hum about 400Hz?
the signal is locked  with 10MHz GPS DO
but it does not sound stable at all
 tuning with a 23cm receiver there is a huge AM tone  IMD around the carrier

When locking to the ADF onboard 10MHz  X-tal oscillator ref
this AM tone IMD  is much weaker but still not clean

still searching for a solution that makes the ADF4351A output clean to be useful as LO generator

The Progrock output is more clean but  also showing irregularities  absolute not Xtal T9
It can not be used  to replace the 23cm l.o.  96MHz Xtal
this experiment seems to end  here

 to make a GPSDO 96MHz  LO  for the 23cm  have to find a better solution

video clip + sound    !size 134MB

    broad  spectrum  output


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SPF5189z Low noise preamp 23cm

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It was stable  50mA  at 5V   few days,  but sudden the current went up to 100mA
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Having relative poor signals on the local 70cm / 2m channels using this Diamond collinear 70/2 combi antenna at a height of 25m. I needed to investigate what could be wrong.
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3W should be enough for a comfortable noise free FM signal. But only 27km away at PA0A the signal is weak too weak something must be wrong? I made a simple reference dipole of 2x17cm CU wire.
With this dipole the signals where totally worse. So the Diamond does work?
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This  antenna is rainwater close in its normal vertical mounting position. But take care if your mast can b…

Nice opening10m and 12m to S.A.

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