MK II build power adaptor

[emerswin]

Hello all. I built the MK II tonebender pos ground version from the GGG site. It sounds amazing and works perfect with the battery installed. When I try to plug in the pos tip adaptor from my fulltone black box it doesn't work. Is this another case of "fuzz face type cuicuts don't like adaptors...just live with it!" or do I pull the whole thing out of the box and trouble shoot/resoldier? Any thoughts!

[phillip]

I have a NPN Negative ground version of the MKII that works perfectly with an external power supply, but things get a little tricky with positive ground.

I'm not sure what the Black Box is...is it a power distributor box?  If so, I would image that it's designed for negative ground circuits, so if you're trying to power negative ground circuits with it at the same time, you'll short circuit the supply...you'll notice it starting to get very hot  Positive ground circuits require completely seperate power supplies so that they don't short.

Another major concern would be that the DC power jack could be wired backwards, causing the PNP transistors to have reverse polarity, which could damage them and cause them to become noisey.

Phillip

[emerswin]

Phillip thanks for the reply (and I love your site and boxes look amazing). THe black box is like a voodoo labs power supply. It has islolated - tip and pos tip outlets.  I used the pos tip and went into my MKII with no luck.  That should be the correct power type...right? The wiring looks correct, I thought about re-solder just to check. I've had the same problem with fuzz face and power adaptors too....