[sdiy] Help trouble shooting noisy circuit
Joe Frey
frey at radioles.com
Mon Jan 13 00:03:55 CET 2025
Hello, more than a decade ago I built with Harry Bissell's help a pitch
to voltage circuit and an envelope follower and then built some
supporting boards: power supply and two invert-offset circuits. One of
the invert-offset boards is not functioning properly. It is a photo
etched circuit board unlike it's brother that was made on strip-board.
The invert and offset functions work properly but the output has a high
frequency wave in it whether there is an input voltage or not. The
brother circuit on strip-board works fine. Same power source for both. I
have checked the component values(there are only resistors), checked all
the traces with the circuit on paper, re-flowed all the solder joints
and replaced the TL072 with others. I still have the issue. What should
I look at next?
Is it possible that a faulty IC socket could produce this effect? I
didn't change the socket because this basement darkroom circuit board I
made then seems pretty fragile.
Thanks for any help. JoeF.
More information about the Synth-diy
mailing list