The first step is to check voltages - at the power pins of the chips. Feel about to make sure no part is getting hot.
Make sure you have the diodes all the right way around, Make sure you haven't mixed the zener with a regular diode.
Second - check the voltages at the outer tabs of the pots. Some will be at 0V or power rail voltages. Some will match the voltage you are feeding into the inputs. Check that the voltage at the wipers change when you move the pots. (for the CV ones, you obviously need to feed a voltage into the CV inputs.)
Make sure you have the diodes all the right way around, Make sure you haven't mixed the zener with a regular diode.
Second - check the voltages at the outer tabs of the pots. Some will be at 0V or power rail voltages. Some will match the voltage you are feeding into the inputs. Check that the voltage at the wipers change when you move the pots. (for the CV ones, you obviously need to feed a voltage into the CV inputs.)
On Fri, Jun 12, 2015 at 10:46 PM, Jorgen Van De Burgt jorgen.vandeburgt@... [cgs_synth] <cgs_synth@yahoogroups.com> wrote:It's 3904 and 3906s all round as specified. I used a component kit from Elby.Coincidentally, the one problematic jack is the only different one from all the others. Still, that's not what is giving me the other issues...
Op 12 jun. 2015 om 13:51 heeft Ken Stone otherunicorn@... [cgs_synth] <cgs_synth@yahoogroups.com> het volgende geschreven:It is almost certainly a construction error on both counts. It's hard for me to say what is going on when I have never seen the fault condition myself. "Transistors all in backwards" worries me because you did not specify the type of transistors you are using. They may not need to be in backwards. Correctly built, the circuit should not be able to short out a power rail.On Fri, Jun 12, 2015 at 9:03 PM, jorgen.vandeburgt@... [cgs_synth] <cgs_synth@yahoogroups.com> wrote:Ok this is interesting. Problem #2 persists after I disconnect the wire from D to the problematic jack. Since only the ground line is connected, what's going on? None of the other jacks that are on the same ground line show this behaviour :S
Any input on the lack of oscillating BTW?
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