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Cgs synth

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Re: cgs29 wave multiplier problem

2012-11-13 by sasami@hotkey.net.au

CA3080 is the same chip as LM3080.

You have a problem with a feedback resistor somewhere. One of them is too
high a value, or has a bad joint. It could be the 100k around IC5a, any of
the 10ks on IC5b,c,d, and possibly, but not likely, the 10k around IC4c. I
would start with the 100k and work backwards along the chain.

Ken

>The main folder section triangle and pulse outputs are identical. They are
both outputting what I think is a 'squared' output. I don't have an
oscilloscope, but with a fixed voltage or an lfo on the triangle input, the
output switches between +/- 15 volts, nothing in between.
>
>The pulse width modulation section doesn't effect the output. The offset
and folds cv sections are working correctly, which is what tricked me at
first. The output voltage just switches between +/- 15 volts, but it does
fold the original waveform, so that switching occurs at different points of
the waveform. if that makes any sense

_______________________________________________________________________
Ken Stone sasami@... otherunicorn@...
Modular Synth PCBs for sale <http://www.cgs.synth.net/>
Australian Miniature Horses & Ponies <http://www.blaze.net.au/~sasami/>

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