Working on a Big Muff (Green Russian)

[sgmezei]

Alrighty, so a buddy gave me his Green Russian BMP to replace the broken battery snap. No problem I say. I want to put in a dc jack on the back for our usual wall wart setup.

I know there are a ton of versions and I came across a thread stating some of them were Positive Ground. I am frustrated going through a million threads so hopefully I can get some help from my Comrades here.

Is this a positive ground effect? It is made in Russia and has the massive green enclosure. I measured the positive and negative on the board and it reads normal to me. I put red probe on red battery snap wire and black on black. Even the PCB has + where the red wire is and - where the black is.

I just don't want to mess it up. It is a good buddy's.

[jkokura]

Positive ground? Not likely. Perhaps PNP instead of NPN, but not positive ground. At least I've never read that. Got a link?

Jacob

[sgmezei]

Okay now I cannot find the article which states it is Positive Ground.

So I am going to go ahead and wire it with the normal madbean wiring method.

Anybody see any issues with this? Jacob?

[jkokura]

nope.

Jacob

[sgmezei]

All is well. Worked like a charm and was totally normal. Thanks for the input Jacob.

[Scruffie]

There was one model of the Big Muff that was positive ground, wasn't a Sovtek though.

The positive thing probably comes from the fact the old phono DC jack sockets they used were wired for positive tip, not ground.