BZZZZZZZZZZZZZZZZZZZZZZZZTTTTTTTTTTTTTTTTTTTT!!!
Wrong answer Steve.? :-)
I hope that I mentioned in the write up that I changed it to
10K.? Purpose?? To lower the operating voltage of the Colpitts
oscillator to near 8V to reduce the current through the crystal.
This reduces heating and reduces drift so that the frequency
readout is going to be closer to the actual operating value
in another circuit.? Of course, you mileage may vary due to
other factors.
thanks,? :-)
chuck, aa7fo
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On 3/27/25 13:26, Steve Ratzlaff via groups.io wrote:
The schematic still has a typo--R1 should be 47 ohms, not 10 k ohms (other than the crystal which is mentioned).
On 3/27/2025 12:13 PM, chuck adams via groups.io wrote:
Gang,
Note.? Crystal in wrong place on both pages.? I had that corrected when
soldering as I recognized the error.? Nice to have the Colpitts circuit
memorized after many years of using it.? Also, in layout, the two caps
were missing, but again I'm using both pages as I build to double double
check.? It does help catch a lot of errors when you are rushed.
FYI
chuck, aa7fo
