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PLL based FM Tx

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There have been overtone crystals in the past that operated directly at 145MHz, for 2m band transmitters without multipliers.

However, it was never a good idea, and the more normal method was to use a 12MHz one and multiply it 12 times - this also enables you to get decent NBFM whilst using a crystal.

Any remotely modern method though uses a PLL, with a free running LC oscillator locked to a much lower frequency crystal.

they are sold even today
 
I once used a CD4046 PLL to make a stable 146 Mhz FM transmitter. The VCO section of the CD4046 is unused. <..> works for small FM deviations, say up to +/-10 Khz, and has the stability on the order of a crystal oscillator..

This is for 2m NBFM, right?

Which PC did you use? the 'digital' one (2) or the NOR-gate one (1)?
 
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