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Author Topic: Replacement pots for MT200  (Read 8070 times)

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calan

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Replacement pots for MT200
« on: Time Format »

Can someone point me to some replacement pots for the MT200?

Values, part numbers, and a source (preferably Digikey) would be great.   ;)

*****

I may have another issue, but I think I fried the B channel pot while cleaning it. It was a bit scratchy, but working. As I was turning it back and forth to clean it up, it suddenly got very easy to turn, and the amp is now stuck in mono mode. Even when using both input and output jacks, both channels are controlled by channel A's volume pot. Otherwise, the amp still sounds fine.

« Last Edit: Time Format by calan »
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MarshallJMP

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Re: Replacement pots for MT200
« Reply #1 on: Time Format »

These are A50k pots,so 50k log.Can you post a pic so i can see what model it is?

Now the problem you have doesn't look like a pot problem.Did you clean the jacks too?
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calan

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Re: Replacement pots for MT200
« Reply #2 on: Time Format »

A external pic of the amp, or the internals? (It's still in the rack for the moment, but I'll yank it soon).

I didn't clean the jacks. It was hooked up in stereo and working, but with a scratchy B pot. Powered it off, cleaned the pot, felt the pot go really light, and when I turned it back on it was in mono mode. Removing and reinserting the rear plugs a few times doesn't change anything.
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MarshallJMP

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Re: Replacement pots for MT200
« Reply #3 on: Time Format »

A pic of the pots.

Again i find it strange.Seems more of a jack problem since these do the switching.
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rnolan

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Re: Replacement pots for MT200
« Reply #4 on: Time Format »

Probably a good idea to change the jacks as well while you have it open, and from what MJMP says, as they do the switching (mono to stereo mode), that could well be why it's now stuck in mono.
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Studio Rig: Stuff; Live Rig: More Stuff; Guitars: A few

calan

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Re: Replacement pots for MT200
« Reply #5 on: Time Format »

Only 3 years later, but here are the pics of the pots (put the thing in the closet and forgot about it  :D)

The original problem "fixed itself". Just have a scratchy channel B pot that needs to be replaced.
« Last Edit: Time Format by calan »
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MarshallJMP

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Re: Replacement pots for MT200
« Reply #6 on: Time Format »

Better late than never hahaha  :thumb-up:

These are 16mm alpha pots pcb mount A50k.
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calan

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Re: Replacement pots for MT200
« Reply #7 on: Time Format »

Thanks much. Do you happen to have a source or manufacturer part number?

I can probably browse around on Digikey and find something similar if not.
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MarshallJMP

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Re: Replacement pots for MT200
« Reply #8 on: Time Format »

Where are you from?
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calan

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Re: Replacement pots for MT200
« Reply #9 on: Time Format »

central Oklahoma
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MarshallJMP

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Re: Replacement pots for MT200
« Reply #10 on: Time Format »

https://www.jameco.com/z/RV16AF-20-15K-A50K-Taiwan-Alpha-Electronic-50K-Ohm-60-mW-16-mm-20-0-235-Inch-Knurl-Shaft-PCB-Mount-Audio-Taper-Potentiometer_2269215.html
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calan

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Re: Replacement pots for MT200
« Reply #11 on: Time Format »

Awesome!

So that is a direct replacement?

I'll order 6 or 8 at that price.  :)

EDIT:

Couple more questions if you don't mind...

1). Is the presence pot the same?

2). Anything else I should pick up and replace while I'm digging around in it? (I replaced the neon lamp and a couple of resistors a few years ago).

3). Is there a relatively easy way to get a bit more power out of it? I'm flashing the yellow LED's while driving a couple of 8 ohm 1x12 cabs, and it's no where near as loud as my 15 watt 5150 LBX II driving them directly at half volume, with the attenuator on (although to be fair, the LBX II is a tube amp, and is INSANE for 15 watts. :D )
« Last Edit: Time Format by calan »
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MarshallJMP

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Re: Replacement pots for MT200
« Reply #12 on: Time Format »

That should be a direct replacement from what I can see.

The presence pot is a stereo C10k pot, also 16mm but C types (reversed log) are harder to find.
I found these but it's in the UK
https://www.hificollective.co.uk/catalog/alpha-potentiometer-stereo-c10k.html
« Last Edit: Time Format by MarshallJMP »
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calan

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Re: Replacement pots for MT200
« Reply #13 on: Time Format »

Thanks much for all your help!
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MarshallJMP

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Re: Replacement pots for MT200
« Reply #14 on: Time Format »

No problem, looked in my own stock but I only have the single version of a C10k
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