It looks like the idea is a goer!
Today I checked the transverter's LO leakage, TX image and harmonics and there's no significant difference in the levels between driving it at 124 to produce 2300 and 144 to produce 2320MHz.
I'm now pressing ahead working out the changes required to the G4DDK Anglian transverter kit so it can produce 124MHz with 28MHz drive.
I've already modelled the main 145Mhz bandpass filter using QUCS and it's looking like a few capacitor value changes to drop it's centre frequency down to 125MHz. Changing the crystal oscillator from 116 to 96MHz will be easy as there's already a 96MHz version of the G4DDK Butler Oscillator in Sam's G4DDK2001 multiplier design that I can copy. I just need to change the second stage values so that it buffers at 96MHz instead of multiplying.
A word of warning if anyone else is considering using 124MHz as a drive frequency drive. You'll need to keep the drive power as low as possible and the leakage to a minimum.
Why?
Because 124MHz is in the air-band!
Be warned!
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