[sdiy] Why you should never tech on too little sleep...

[Peter Grenader]

The PCB design is completed the my VCO and I've been very careful checking
the art to the schematic and in so doing,  found a part I forgot to document
of the the schematic on the cross fader.  So I become totally paranoid and I
decided it would be best to buzz the prototype out against the schematic
(and PCB) in that section, right?

OK, so I'm buzzing out it out and something very odd is going on that's
driving me crazy...I've got a pull down that's reading ground at both sides,
but when I look, its not connected to the second side that I can see. Weird.
OK, so it's another part it's connected to that doing it and leading from
that pulldown is a 10K across an op amp, and THAT's also shorted to ground
(yet miond you the circuit is working and with these conditions, it
shouldn't be).  I couldn't figure it out  I  looked at both sides of the
board a trillion times, I can't see it.  I started cleaning flux off like
mad thinking it could have caused a short on my vector board, and it does
nothing.  Then I notice that when I buzz from +V to those nodes, they are
also shorted (YACK!) - BUT, when I buzzed directly from +V to ground, no
short.

So, I'm going insane, right?

I changed the batteries in my beeper.  No diff.

Have you all figured out what I was doing wrong yet?

Yes Kids, I HAD THE POWER ON THE BOARD.  ANd during this process I was
poking around with a hot iron checking for shorts.  Luckily, everything
still works.  I'd say I'm fortunate.

GOOO TOOOOO SLEEEEEEEEEEEP.

- P 
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