I am looking to find a direct replacement for the potentiometer in the photo below (linear (A) 20K - around 10.5 or 11mm base diameter, and the shaft length is about 15mm (or 18mm including the small bit of metal at the base of it)). I think they are Alpha brand. I don't know if there is alternative, but I figured only the exact same (or close) potentiometer would fit the PCB.
I've looked everywhere (in the UK) but all I can find is 16mm base diameter potentiometers. In addition, pretty much all these potentiometers have the lugs on side instead of below the shaft (although perhaps could cut that off).
Any help much appreciated, I am honestly not sure how to find it, I know this a pretty boring plea for help, but I have tried various places and search terms, I thought it would be pretty much standard and easy to find - any ideas?
I've looked everywhere (in the UK) but all I can find is 16mm base diameter potentiometers. In addition, pretty much all these potentiometers have the lugs on side instead of below the shaft (although perhaps could cut that off).
Any help much appreciated, I am honestly not sure how to find it, I know this a pretty boring plea for help, but I have tried various places and search terms, I thought it would be pretty much standard and easy to find - any ideas?
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The pin spacing, other than the value, is going to be the most important, have you looked at RS Components?
Is that middle one a dual gang ?
Any possibility of desoldering them and then opening them up to clean and retension/move the wiper to fresh track. I done that many times on single gang pots, the dual may or may not come apart quite so easily.
These miniature pots can be difficult to source as a spares item.
Any possibility of desoldering them and then opening them up to clean and retension/move the wiper to fresh track. I done that many times on single gang pots, the dual may or may not come apart quite so easily.
These miniature pots can be difficult to source as a spares item.
The single gang A20K is definitely physically damaged, not sure if it is salvageable, it rocks backwards and forwards (between the pot bit and the brown rectangle bit that hangs down, so not a great place - don't think it's possible on the bigger pots) and only works properly if positioned in exactly the right way. The problem is one of the dual gangs has also split in two on the brown bit, I think that connection might be broken too, so I might need one of those also - surprised they are so hard to come by, that is a shame.
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If they are physical broken then they have to be replaced. Small outline pots are available but they would have to be mounted differently. If you can screw the pots to the face plate then you stand a chance but the replacements would have to hard wired into place.
Another possibility is small outline parts with pins. You could redrill the PCB to accept these but again mechanical stability is an issue and they would need securing to the face plate.
CPC have a decent range (I haven't trawled through them all) so you might find something that can adapted.
Another possibility is small outline parts with pins. You could redrill the PCB to accept these but again mechanical stability is an issue and they would need securing to the face plate.
CPC have a decent range (I haven't trawled through them all) so you might find something that can adapted.
I wouldn't normally recommend this but have you looked at places like these. There are two dropdowns to select types and values:
Dual Stereo 10K ohm lin Linear Log Logarithmic Pot Potentiometer And Knob | eBay
Dual Stereo 10K ohm lin Linear Log Logarithmic Pot Potentiometer And Knob | eBay
Cheers, still looking - it's something like this 12mm Pot 10 but no idea where they are sold though - mouser had some that looked almost right.
Plan B - since this is proving more difficult than I imagined I'm wondering whether I can use a big potentiometer and wires from it to the PCB - looks like it would just about fit (with solder connections to the side or upwards).
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Ok, soldered the wires onto the PCB - I have to hand a big A10K potentiometer (not A20K) - is it worth a shot?
Or should I just order a 20K one? The big ones being easy to find.
Or should I just order a 20K one? The big ones being easy to find.
Hard wiring is certainly an option, however the orientation has to be the same, if not then the end stops would be in the wrong place and the rotational range would be upside down.
I am afraid the schematic is not available AFAIK, which is a shame - it is a Demeter Real Reverb unit - the A20K pot is the "output" level control. If I can get this one working I'll at least have channel A sorted.
The dual gang one is the mix control and is on channel B. It says A10k, C10k on it - am I right in thinking this is an uneven taper pot with linear 10k closest to the shaft and anti-log (reverse) 10k furthest from the shaft? I've not come across such a thing before.
Thanks.
The dual gang one is the mix control and is on channel B. It says A10k, C10k on it - am I right in thinking this is an uneven taper pot with linear 10k closest to the shaft and anti-log (reverse) 10k furthest from the shaft? I've not come across such a thing before.
Thanks.
You should be able to use the 10k for the volume. Does the dual gang say A on one and C on the other? I presume you've found this? - Potentiometer's Tapers
Thanks, for avoidance of doubt as I'm not well versed in this, it looks like the attached - A on one and C on the other (it's completely snapped apart at this point so definitely need a new one after removing it).
I am not sure this one will easy to source though, I can't seem to find it even in the large format.
Cheers
I am not sure this one will easy to source though, I can't seem to find it even in the large format.
Cheers
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That would be difficult to find for sure, there is an alternative though, it is possible to use a linear potentiometer with an additional resistor to produce a "fake-log" pot. Have a look here...towards the bottom of the page it shows how you can modify potentiometers Potentiometers (Beginners' Guide to Pots)
This format of pot is totally standard and easily available ...Ebay etc.
The dual gang pot seems unusual...what is the make/model of the gear, and what is the circuit function of the dual gang pot ?.
Dan.
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