JSX Hum - SOLVED (For me anyways)

[LeeWinn1974]

My JSX 212 combo always had a minor hum since the day I got it (used). I tried a number of solutions offered by Peavey and by forums with no luck. Recently I replaced the filter caps and problem solved! I have attached a list of all the caps, their, p/n, value, quantity and location. I was able to purchase all of them through digikey. They are Nichicon replacements. Lead spacing is correct and the heat rating is actually higher than the original. Other than that, the values are the same as stock. The snap-in caps that Peavey used have two terminals on the ground and the replacements only have 1. This didn't cause any issues and the replacements fit fine.

Note: The glue sucks to deal with because it's messy. Just use a heat gun to loosen it up. I went a little too long and it gets stringy.

I hope this helps someone!

P/N	VALUE	QTY	LOCATION
493-8353-ND	680U @ 350V	2	C42, C47
493-8344-ND	220U @ 350V	2	C43, C48
LGC2H101MELZ30-ND	100U @ 500V	1	C44
493-5884-ND	22U @ 450V	2	C45, C46
493-UBT1J101MPD8-ND	100U @ 63V	4	C49, C51, C52, C56
493-4913-1-ND	1000U @ 35V	4	C54, C58, C61, C62
493-7188-ND	4700U @ 35V	2	C55, C57

[misterc57]

I'm working on one now that has a hum when the master volume is turned up, all channel volumes at zero and no input signal. No hum with master volume at zero. Was this similar to yours?

See https://music-electronics-forum.com/...-120-cycle-hum

Thank you