Hi all.
Hopefully a simple fix. I have a fuzz face PNP type circuit. it works really well with a 9v battery, however when I use a 9v plug pack problems start.
The issue is this. I have a single plug pack driving multiple devices. When all dc is plugged in it works (power to the devices in the chain). When I plug a 1/4" phono from fuzz to the little 9v amp input, power is cut. this happens with all devices in my collection. I had a thought that it is because of the positive ground the circuit has, but i cant work it out. no hair left too pull out.
cheers.
Luke
Hopefully a simple fix. I have a fuzz face PNP type circuit. it works really well with a 9v battery, however when I use a 9v plug pack problems start.
The issue is this. I have a single plug pack driving multiple devices. When all dc is plugged in it works (power to the devices in the chain). When I plug a 1/4" phono from fuzz to the little 9v amp input, power is cut. this happens with all devices in my collection. I had a thought that it is because of the positive ground the circuit has, but i cant work it out. no hair left too pull out.
cheers.
Luke
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If you want to run it all from one supply youll have to convert your fuzz face to the NPN version (reverse the capacitors etc) or stick to using the battery . You cant ground the positive in one unit and the negative in another , run off the same supply rails then connect the 2 grounds together either accidentally or on purpose as you are shorting the positive to the negative ..............see ....fuzz face help .....thread in Instruments and amps for some related info .
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I do remember seeing, some time ago now, an effects psu advertised with eight, independent, floating, 9v outputs, rather than the usual one.
This had two possible uses: Allowing positive ground effects, usually a pnp fuzzface to be connected, and elimination of ground loops. Not sure who made it.
This had two possible uses: Allowing positive ground effects, usually a pnp fuzzface to be connected, and elimination of ground loops. Not sure who made it.
there are few companies out there that do them, what i don't like about them is they bring mains voltage to your feet. In live music situation this is hazardous (beer spillage, punters throwing water and so what at you) generally I like to keep all mains voltages on the back line.
I have in mind to make one that takes a plug pack power supply, say 24v (this is voltage requirement of one of my pedals) then split it out into and 18v and several 9v outputs. still thinking about it really not committed to sit and build yet.
cheers
I have in mind to make one that takes a plug pack power supply, say 24v (this is voltage requirement of one of my pedals) then split it out into and 18v and several 9v outputs. still thinking about it really not committed to sit and build yet.
cheers
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