weird dual NPN and PNP circuit wiring question

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weird dual NPN and PNP circuit wiring question

Postby noiseuoh » 26 Feb 2012, 23:13

so, im building a kind of super tonebender MKII with a separate NPN silicon tonebender circuit and a PNP Ge negative ground MKII wired on a DPDT so you can switch between the two circuits inputs and outputs.
i have been having a hell of a time biasing the Ge PNP negative ground MkII so i decided to just make it a positive ground circuit.
now, the problem is that i dont know if its possible to wire a negative ground circuit and a positive ground circuit on the same DC jack.
should i change teh DPDT input/output switch into a 3pdt, with the positive power added onto the switch. so that when it is in one position lets say the NPN SI MKII position, the positive line from the DC jack is also powering the circuit. whereas if its in the PNP Ge MKII position the postive rail is providing a ground for the circuit.
does this make any sense?
any and all help is extremely appreciated.
Thanks
noiseuoh
 
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Re: weird dual NPN and PNP circuit wiring question

Postby wesc » 05 Mar 2012, 07:20

I dont think you can wire pnp and npn on the same power circuit. When I use a daisy chain with my PNP fuzz face, it works, but all other negative ground pedals connected to the daisy chain dont get power. I think you would need an isolated ground for each. I think you could make it work by using a 3pdt switch and wire the dc jack to that so it disconnects the power to one circuit and connects the other. Only one on at a time though.
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