14-02-2017, 12:47 PM
My initial reaction was that it was similar to a Colvern wire-wound pot and that you might be able to rob the element out of one of those, if you could find one but I think they are wound on a flat insulating strip - not the strange shape you have there.
It looks as if it has a strange law with maximum change of resistance at both ends, reducing towards the centre, possibly having a flat spot in the centre where that projection is.
Having multiple breaks means you can't use the old dodge often found in the brightness controls of Bush TV22s and TV24s of jamming a small piece of silver foil (from a cigarette packet) between the outside of the element and the housing!
If you can't find a replacement (and I don't fancy your chances of rewinding it) perhaps you could create a suitable bodge with two small pulleys - one inside the pot with a couple of holes in the casing for a bit of drive cord to the other pulley on an externally mounted pot.
You could replicate that peculiar law by using a higher value pot with resistors of suitable value between the slider and both end of the track.
It looks as if it has a strange law with maximum change of resistance at both ends, reducing towards the centre, possibly having a flat spot in the centre where that projection is.
Having multiple breaks means you can't use the old dodge often found in the brightness controls of Bush TV22s and TV24s of jamming a small piece of silver foil (from a cigarette packet) between the outside of the element and the housing!
If you can't find a replacement (and I don't fancy your chances of rewinding it) perhaps you could create a suitable bodge with two small pulleys - one inside the pot with a couple of holes in the casing for a bit of drive cord to the other pulley on an externally mounted pot.
You could replicate that peculiar law by using a higher value pot with resistors of suitable value between the slider and both end of the track.
