Hi there,
I recently made my own pcb for the 1222 oscillator and implemented some of the fixes listed in some of the threads here. I routed the power backwards when first trying to power on the module. Ended up fixing that but it doesn’t work now either. I have tried replacing every ic but with no effect. The weird thing is, when i set the rotary switch all the way to the left, the sawtooth output works, but the other outputs don’t. And when the switch is in any other position none of the outputs work. So the only output that does work is the sawtooth output when the switch is in the leftmost position. Does anyone have any clue what’s going on? (also good to mention, i never powered it on before powering it backwards, so i have no idea if it should be working or if the problem is in the circuit itself).
I managed to fix the rotary switch, the wiring was wrong apparently. But the issue of the other waveforms not working still persists. So now the octave select works and the sawtooth works on all positions, the other waveforms just don’t make a sound.
If one waveform is being produced, they all are being produced. The only possibility is that they are not getting from the 3340 to the TL074, or from the TL074 to the output jacks. Use a scope or an audio probe to verify the signals are on 3340 pins 4 and 10, then see if they get to TL074 pins 3 and 12. If so verify they are on pins 1 and 14, then see if they get to the jacks board pin header/socket and from there to the jacks. Where they disappear is where you need to fix a couple solder joints.
thanks for the reply! Fortunately it ended up being a really stupid problem i made myself. I didn’t remember which way i intended my pcb to be so i soldered the jack sockets on the wrong side of the pcb, it works now! The whole time i was listening to the CVin lol
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