Rewiring the 1/8" power socket on an old MXR Phase 90 - advice needed!

Philtre

I've got an old MXR Phase 90 which uses the old style 1/8" power jack and I think is wired positive to case? What are my options to bring it up to date? Could I drill a new hole and fit a new type barrel power socket?

Here's a piccy of the guts:

ICBM

Yes, or you could just use a conversion cable. It's wired with the negative to case - what may be confusing you is that there's no negative wire to the jack, it's done via the casing.

Philtre

@ICBM Thanks for that. Yes, you're right. I traced the wires with a continuity tester and figured it all out. On the other hand, as you say, it's probably easier to buy one of these - https://www.amazon.co.uk/ammoon-Positive-Supply-Converter-Guitar/dp/B06XRKG7ZC

Winny_Pooh

I have a phase 45 on my bass board that I modded for a regular dc input and added an LED on the side of the pedal so it still looks correct. 

Philtre

I'm feeling a bit smug with myself. I removed the old socket, drilled the original hole a tad wider and then fitted a modern barrel socket in place, soldered it all up and it works great.