Given xtal specs can a Colpitts oscillator component values be successfully modelled?? I have changed the oscillator part of a rock bound LO on a software defined receiver to work with a crystal of 461.5 kHz fundamental using values fro C10, C11 and C12 from a US user, with a different make of xtal. Note the new component values printed at the TOP of the schematic please! His starts and runs reliably. Mine sometimes needs me to touch or fiddle with the pcb to get it going. I have managed to track down the full spec of the new old stock xtals I have, is this sufficient for someone to model it please? I am a newbie well out of his comfort zone, so please make it as simple as possible to understand! Googling suggests modelling such xtal controlled oscillators is a bit fraught, not that I would know where to start with the likes of SPICE....
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