Orion / Orion II Synthesizer Alignment Procedure
Start on the 80 meter band, LSB, 1kHz tuning step.
Set 44.55MHz TCXO on frequency at J4.
Check for presence of DDS output at TP1. DDS frequency runs from approx: 2MHz to 9.425MHz and rolls over four times in the 80 meter band.
Monitor synthesizer output frequency at J3.
Connect digital voltmeters to TP3 and TP10 to monitor VCO control voltages.
Start with all four VCO trimmers at minimum (triangle on trimmer rotor points to flat side of trimmer).
Watch TP10 and tune all the way up the band (>4.0MHz) to the highest VCO control voltage. Use VCO4 trimmer C157 to set this voltage to 5.5 volts. This is called the “set voltage”.
Now use VCO2 trimmer C64 to set TP3 to the “set voltage” (usually 5.5 volts). Tune down from the top of the band to find the first roll over point. TP10 voltage will take a step down at rollover. TP3 should move smoothly through rollover without a big step. The frequency counter on J3 should show 1kHz steps through the rollover area.
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