To all,

I was able to find a parts list for this amp (no schematic) but that is enough to help me place the right pots in their proper places.

Thanks to all for your responses. For now, I am waiting on parts for this one.

Too many other pressing projects to work on.

Thanks again.
Cheers!

Thanks for the quick response.

I take it then that unless damage is evident, the pots that survived will not start cracking off.
No reason to fix what isn't broke.

I cannot seem to find a source for the schematic.
One of these is marked B200K (omega), I assume a 200K Ohm pot.

The others are marked A1M (omega), which I assume means Alpha 1 Meg ohm Audio Taper pot.

There is a B200K pot as the TREBLE control of the overdrive circuit. Can I assume the broken B200k is for the treble control on the clean circuit? Don't know why, but I would've though volume instead.

Or can you tell me of a good source (in USA) for the schematic and these little pots?

Thanks again.

Hello.

This is my first post.
I have a Marshall G30RCD practice combo that has been sitting around for awhile. I got it for the kids years ago. Dusted off it looks brand new, very clean inside and out. When turned on it plays, on both clean and overdrive, but no ability to change volume, tone or gain. So, in opening it up I discovered that 5 of the control pots were broken off at the base.


The pots broken are CLEAN CHANNEL - Volume, Bass, Treble. OVERDRIVE CHANNEL - Gain, Bass.
The rest of the pots (OVERDRIVE CHANNEL - Contour, Treble, volume, & MASTER - reverb) look fine.

So, the broken pots will get replaced. I expect that will fix the problem.


My question is, should I replace ALL of them?
I suspect the amp was either dropped or pushed over which resulted in cracking the 1st 5 pots.
Is age a problem with these cheap little pots?


Any advice is appreciated.