Still Fiddling with the Knight CPO circuit
It's a tickler coil type of audio oscillator circuit, mentioned previously:
https://wb9kzy.blogspot.com/2025/02/knight-transistor-code-practice.html
Here again is the schematic:
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note the colors of the transformer leads |
I haven't gotten it to work yet - I did scare up a 1k:8 audio transformer but I'm not sure if that is what is called for here. I did find this nice transformer lead color diagram:
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the red and blue wires on the primary might need to be swapped ? |
source: https://tubesound.com/rtma-color-codes/#audio
One reason why my try didn't work might be that the leads might need to be swapped, either red and blue OR green and black. It seems to me that I did try that because that's a common reason why these kinds of circuits don't work.
Also, I haven't found a germanium transistor that is comparable to the CK722 in my junkbox.
I will also have to try and find my Allied databook, it might have more transformer info.
I'll keep plugging !
Best Regards,
Chuck, WB9KZY
http://wb9kzy.com/ham.htm