Reverse Polarity Help!

[Stoneham11]

Hello I am working on a TS808 and got it built but hooked it up accidently to a positive tip supply 9V DC.
I tried it today and it passed signal in the off position but in the effected position no signal would pass through and I was getting whistle sound.
Did I fry something?
Please Help?
I will send pics if need be.

[Barcode80]

you probably fried the IC. especially if you don't have a protection diode on the 9v line. replace the IC and see if it fires up. if not, and you left the positive tip in too long, you could have fried any polarized caps, so replace those.

[Paul Perry (Frostwave)]

When trying to repair something, the first question is, did it EVER work?
If it worked once, and doesn't now, then something is fried.
But... where can the 'whistle' be coming from? I would think, only the IC can amplify & make a whistle (via some feedback, maybe as a result of bad layout or error). In which case, replacing the chip may not help.

[petemoore]

  Run it through the debugging tasks..measure the pin voltages etc.

[Stoneham11]

what voltage should each pin be.
and also the pedal never worked I had made a power supply out of a battery snap and a DC power plug I had it center positive for the Fuzz that I built.
So as soon as I finished the TS808 I tested it right away with that power supply and it didn't work so I realized that I had the wrong terminal on the power supply adapter so I switched that around and and it still didn't work and thats when I realized that the polarity was reversed on the power supply.
I switched it around and the LED started working but still no sound when turned on.
I just replaced the Diodes and IC and still have no sound.
Should I replace the Polarized Capacitors now?
Thanks for everyones help I appreciate it.

[Barcode80]

if it never worked to begin with, you need to debug the circuit as such. the polarity reversal may have nothing to do with it.

[GibsonGM]

1) Supply, Vr, and Pin Voltages
2)Audio Probe!
3)Continuity tests and Magnifying glass!
No sense changing caps if they're good...measurement & listening will tell you if they are or not...were the diodes you removed blown?

[petemoore]

  Measure everything possible with the circuit/PS before applying power to the circuit...next time...
  Check for shorts, that V+ indeed goes to + of PS etc.
  Even with all that the protection diode is worth the V drop.
  There is no reason the debugging information shouldn't be applied, it'll find problems faster than the 'hit/miss/related texts type'.

[petemoore]

  For pin voltages..the V+ PS pin 8 on a dual oa should be the voltage of the power supply like battery if a filtering resistor isn't used between PS and circuit.
  Pin 4'd be ground = 0.0v
  The rest of the pins need to be within operational standards, something between V+ and Gnd. .. around 1/2v of measured supply potential.

[Stoneham11]

Thanks For everyones help I'll keep you posted