Need to ID this JP slide pot - Page 1
Forum section: electronics / repair

author: CZroe
author_rank: Contributor
timestamp: January 06, 2021, 01:33:06 am
content: Pics:https://imgur.com/a/grD2iFzI recently imported an expensive 30 year old Japanese-exclusive Micomsoft XE-1 HE Pro joystick and found that the turbo/auto speed adjustment sliders don't do anything. I took it apart and hit the slide pots with DeoxIT and FaderLube, which made no difference.Both pots were marked A100KΩ 8N on the side and I measured very close to 100k-ohms across it. The wiper was connected directly to one side so it measured 0-ohms or 100k-ohms between each side but had no variance when sliding the plastic shaft back and forth.I desoldered the pots so the wiper was no longer connected on one side through the PCB. After desoldering I couldn't get anything through the wiper prompting me to open one of them up and peek inside. All I found was a plastic base/shaft, a plastic pressure plate, and a springy piece to add tension when you slide... no wiper. That springy piece was between the plastic plates and was definitely not a wiper. How both pots could be missing a wiper is beyond me.I've already given up looking for a compatible replacement from the likes of Mouser, Digikey, and eBay, but it seems to be 35x6x6mm with a 10mm shaft and 20mm travel and, strangely enough considering the application, logarithmic taper. Since I couldn't find one similar enough I've resorted to trying to identify the manufacturer so that I could buy/salvage another and switch the wipers. That's where I'm stuck: I looked all over it for markings to identify who made it but I can find nothing. I looked all over eBay for one that looks close but I'm not finding anything that way either.It seems that most Japanese consumer products from that era stuck with Japanese components but it doesn't look like any of the Panasonic or Alps slide pots I can find. What other brands should I look for? What are some Japanese equivalents to Mouser, Digi-Key, etc (other than DigiKey.jp)?Speaking of Digi-Key, I thought PS20-10PC1A100K from Digi-Key would do the trick if I could bodge it on but I'd have to order nearly $1,000 worth.

author: Audiorepair
author_rank: Frequent Contributor
timestamp: January 06, 2021, 04:55:25 pm
content: I haven't seen that particular PCB footprint before, so I think it unlikely you will find an exact replacement.The Alpha RA2043F-20-10EB1-A100K looks like another candidate for a bodge, you can screw it to the top panel and hard wire it to the PCB, if it isn't too tall to fit.https://www.mouser.co.uk/ProductDetail/Alpha-Taiwan/RA2043F-20-10EB1-A100K?qs=sGAEpiMZZMtC25l1F4XBU1sVVnjISoIH3dBmZgYTtpc%3D

author: CZroe
author_rank: Contributor
timestamp: June 16, 2021, 05:46:57 am
content: Thank you. I went with these linear pots and the footprint was a perfect match:https://www.ebay.com/itm/5pcs-Variable-Resistors-35mm-Straight-Slide-Linear-Potentiometer-B100K-4pin-/312722782130?_trksid=p2349624.m46890.l49286The shaft, however, did not fit the original slider caps very well. I shortened them and filled the caps with Blu-Tack which seems to secure them just as well as the original friction fit.I do wonder why the originals were ever logarithmic for this kind of application. You’d want your turbo slider halfway between minimum and maximum to result in half of the maximum turbofire speed... or half way between maximum and minimum.