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Hey @CHRIS B PINBALLS - does the old one have the same turns? I’m assuming so... this also seems to be the same spec one used in later models. With far more turns to resolve the issue of it falling well out of spec.
The old one didn’t seem readily available, I even asked on this very forum. The response seemed to be. No. So I improvised.
I think the term a “right old bodge” is probably a tad harsh. Sure - not as perfect as a pre-fitted formed one, but I’ve seen far worse “right old bodges” in pinball than this.
The option I would say is to have an “interface board” made up but for it - if you wanted it to look pretty. Like you can get for surface mount to pin through hole NVRAM.
As bodges go, I’m happy with this one, better than a key for... well keys have been used for a lot of things .
I think you'll find its not how many turn but the tolerance of the pot that makes the difference.
The originals were +&- 20%
You can get the same package in +&- 5%
Heres an example. Probably not the correct value but there should be one on there that is. https://uk.farnell.com/amphenol-pih...0-472a0505/trimmer-4k7-0-33w-1turn/dp/3128615
@Vimtoman - +/-% the variance within the resistance value and the turns what proportion of that % each turn varies it?
I am no expert and someone please correct me - because I want to learn, but the way I understood it was for say it was a 10K value with 20% variance and 10 turns - each turn would adjust resistance by 0.2K?
10 turns means you have to complete 10 turns to go from zero ohms to 10K
its a linear pot so each turn increments it by 1K
eg 5 turns you would have 5K
the % is a manufacturing tolerance so you might have at the top end 10K +/- 5% = 10500R or 9500
Also worth saying that the three eddy sensor boards in Theatre of Magic are not quite the same. I think two out the three are the same values on the board. It is worth replacing the pots on all three at the same time, but do them one at a time.