RE: Vintage Toy Synthesiser - Panel - Part 2 (Electronics and Software)

DAB — Sun, 13 Mar 2016 19:18:08 GMT

When you have that many potentiometers in a circuit, you establish interesting resistance paths to ground.

You should probably look at adding some current limiting resistors on some of the inputs just in case you are overloading the analog inputs.

You might also be getting some parasitic capacitance and inductance that might be putting some unexpected signals on some of your lines.

You might need to add some bypass capacitors as well.

Plus, you could have some ground loop issues.

You might want to unplug all of the pots but one and look at how the input responds as you adjust it through its range. You can then measure the amount of current and voltage over each circuit and see if you are introducing issues as you add each potentiometer. You might want so use some diodes to limit some of the values.

Circuits can be tricky, it takes some time to appreciate how to keep each signal path from affecting another.

DAB

RE: Vintage Toy Synthesiser - Panel - Part 2 (Electronics and Software)

clem57 — Sun, 13 Mar 2016 13:27:53 GMT

I was planning on adding an example video of using the panel here, however unfortunately last night my BBB decided to stop working (from searching online for other cases of the symptoms it looks like the processor has randomly blown).

I am sorry to hear that. But was there a way to prevent?

Clem