Simple 1v/Oct oscillator help

KOSMO MODULES
3

Assuming this is about the 3340 ones and you’re using Sam’s stripboard layout, I’d suggest:

  1. Turn the coarse tune knob. If it doesn’t change anything, check the wiring.

  2. Measure the voltages going into the CV adder, via the 100k resistors at the top, marked with “CV” and “TUNE CV” here:

    Annotated Simple 1V/Oct Oscillator Stripboard

    Measure between ground and the top of the resistors, away from pin 15, and add the voltages. You need almost 5 V in total to reach audible frequencies, and about 9 V to hit A4 at 440 Hz.

  3. Check the oscillator capacitor (the yellow one near the 3340).

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