An odd problem for a simple circuit

[analogoutput]

Advice for troubleshooting 3340 based VCO

This is a wiki post; please correct and improve! This is written regarding the 1222 Performance Oscillator module, but similar things apply to the simple stripboard oscillator or other oscillators based on the 3340 chip. For the stripboard version also see If you are not getting good tones from the oscillator, do the following. If with the 1222 you are also not getting good behavior from the tuner, don’t waste time on trying to fix that yet. Get good tones on the outputs first — the tuner won…