A simple problem, I'm sure.

[ballooneater]

A most unusual problem has presented itself!  I am connecting two batteries together (in series) and the voltage magically turns to around 2V...

My setup is as follows:


It could very well be a problem with the batteries, but my multimeter is getting a constant 8-ish volts from each of them.

In case it helps, I am building an Ibanez FL-301 Flanger based off of the Tonepad layout.  No part substitutions that I can recall.  I will provide IC voltages if it would help diagnose the problem.

[aron]

The obvious guess is that there's a miswire and it's dragging the voltage down. To prove it, unsolder the red wire from the power jack and then measure the series voltage with a multimeter.

[ballooneater]

Unwired, it measures the expected 16V.  Would a faulty 12V linear regulator cause this problem? I had it in backwards before...

[ballooneater]

To answer my own question- just replaced it and it had no effect.

[ballooneater]

May as well go for the triple post!

It seems as if the protection diode may have died, it conducts electricity both ways.  I believe I had a 1N4184 in there.  Should it have been a 1N400X or a Zener?

[ballooneater]

Problem solved; thanks for your help, Aron. I'd like to think that without it, I wouldn't have known where to start.  Those tricky diodes are out to get me.