ADF4351a updated

ADF4351a   F1CJN  in a housing   update 24-4-2017
 is a usefull  35 - 4400 MHz generator   locked to 10MHz Trimble GPSDO

2017 in a protective case
detail:  the Arduino  LCD keypad screen buttons are accessible trough  3.2 mm drillings
longer plastic shafts from other push buttons as extension under the front.

The ADF4351a   uses external 10MHz reference by disconnecting the internal 10M XTO
i used a 3 pole jumper to have internal or external ref.
that should be an front option switch  ( to do)
 The external reference is the  Trimble GPSDO 10MHz
It's 30mV sinus shape is filtered and amplified to 3V3 ttl level for the ADF4351a


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    94MB

    broad  spectrum  output