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Showing posts from June 25, 2016

ADF4351 locked by GPSDO

When monitoring the ADF 1296.1 MHz on the 23cm DB6NT  it showes an ugly broad humming signal   switching the ADF to the  internal ref the signal is a  clear tone. This ADF REF input   needs a  10MHz  TTL 3V3 blok fomat  to drive ? Deja vue with the 23cm XTVR  of 30 years ago: The 96MHz X-tal  does not want to work at its designed frequency and is drifting in kHz range at 1152MHz. Since that project I avoid using single xtals since never ever they will work at the correct  frequency. Only use integrated Xtal ocillator modules since then And the NE325 Gaasfet preamp likes oscillating  way more  then amplifying  nothing is changed... I remember long time ago in the 80-ties when we still had exceptional tropo propagation to east EU A pile of  UA UR UC SP at 70cm CW  on 23cm there was UA3LBO but the 23cm Gaasfet preamp just could not handle the strong radar sweeps, every 10 seconds a radar was triggering the fet in self oscillation .  Meanwhile a struggle to get


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