Checking voltages after pot change

[oguinn]

I dropped an Alps pot in earlier today. I am on very little sleep with the new baby so sorry for the dumb question  - will the Speedball voltage checks suffice or are there more I should check?

[Thermioniclife]

Let her Rip.

[oguinn]

I’ll go run the tests when either the baby or my wife wakes up. Thanks, Lee

[2wo]

Probably more useful to do the resistance checks...John

[oguinn]

Some of the resistances change when you add the Speedball, right? It’s been a while since I did it. I guess it’s probably more important to check the resistances at the pot since that’s where things changed.

[Deke609]

Hey Jameson - Congrats on being a Dad!

Were it my amp. I'd just give it a listen. But maybe I'm a bit reckless. Never tried this, but I think the following would test whether the pot is installed and working properly: (1) with amp unplugged and off, turn the pot all the way up; (2) measure resistance between right channel (red +ve) rca input and red signal wire on the 9 pin socket (pin 7?) - you should see relatively little resistance; (3) turn pot all the way down -- the resistance should go way up (assuming it's a 100K pot, I'd expect the resistance to be about 100K); (4) repeat steps (1) to (3) for the left channel (white wires); and (5) check for ground continuity between either or both of the 0V blacks wires at the rca inputs and either/both of the center terminal of the 9 pin socket and/or the middle lug of the terminal strip adjacent to the 9 pin.

If all of that looks good, then give it a listen.

cheers, Derek

[Paul Birkeland]

Or you just turn the thing on and see if it works.

[oguinn]

Or you just turn the thing on and see if it works.

I’ve read your posts long enough to never turn on an amp that’s had work done without at least testing voltages

And thanks, Derek!