If electrolytic cap is backwards, how would I know?

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JVanDe7
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Post by JVanDe7 »

Would the pedal not work at all if an electrolytic capacitor is installed backwards? I'm getting some inaccurate voltage readings on a recent build and since the layout is not confirmed, I'm thinking maybe C9 looks like it's backwards on the layout compared to the schematic.

Here's the schematic...
http://analogguru.an.ohost.de/193/schem ... rdFuzz.gif
Notice how the negative side of C9 is what goes towards R15 (47k)? Well now look at the layout...

download/file.php?id=15574
And see how on C9 the positive side is going towards R15 (47k)? [R15 isn't labelled but it's the standing up resistor above D2]

It seems to me that the layout and schematic contradict each other here. Would this be the cause of these "off" voltage readings?
On the schematic, at Q1 where it says "0.9V" I'm getting .64 volts
Between Q1 and R2 where it says "5.98V" I'm getting 6.6 volts

On Q2 where it says "3.97V" I'm getting 3.3 volts
Between R5 and C5 where it says "5.00V" I'm getting 5.49 volts

On Q3 where it says "0.56V" I'm getting .47 volts

On Q5 where it says "3.32V" I'm getting 3.87 volts
And on Q5 where it says "0.56V" I'm getting .50 volts
“Walk tall, kick ass, learn to speak Arabic, love music and never forget you come from a long line of truth seekers, lovers and warriors.”
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JVanDe7
Resistor Ronker
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Posts: 333
Joined: 26 Apr 2008, 18:49
Completed builds: DAM Red Rooster clone, Zvex Octane 3 clone, Zvex Fuzz Factory clone, Maestro MFZ-1 clone, Fulltone Soul Bender clone, Fulltone 69 clone, Green Russian Muff clone, Dallas Rangemaster clone, Mosrite Fuzzrite clone, EA Tremolo, VOX Clyde McCoy wah, Jordan Bosstone clone, Analogman Sun Face clone...
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Post by JVanDe7 »

Just to elaborate a little - it sounds good and works, but I'm getting some quick decay at certain settings and I'm wondering if there is something out of place that's causing it. That's why I took the voltage readings, and now I'm curious. Thanks.
“Walk tall, kick ass, learn to speak Arabic, love music and never forget you come from a long line of truth seekers, lovers and warriors.”
― Hunter S. Thompson

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