Assuming this is about the 3340 ones and you’re using Sam’s stripboard layout, I’d suggest:
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Turn the coarse tune knob. If it doesn’t change anything, check the wiring.
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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.
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Check the oscillator capacitor (the yellow one near the 3340).