At 03:46 PM 2/21/2011, Dr Skip wrote: >Greetings all, > >I'm repairing a friend's super-duper mega blender (brand name shall >remain unmentioned to protect the guilty) whose variable speed pot has >gotten flaky. It's a very thin design (the pot that is) but I think I >can fit in a replacement. The ID markings aren't readable, and searches >don't turn up anything that looks similar. One lug is cut off, making it >just a variable pin and common. I measure 5k between the cut off lug and >common, but the wiper has gotten so bad that it's really jumpy if >touched or moved. That's the problem as it's used... Rotate the pot to the half-way point and see if you can get any kind=20 of resistance reading between the wiper and each end. The ratio of=20 the readings will tell you the taper. A linear pot will read about the same from wiper to both ends. An=20 audio-taper pot will read about 10% from wiper to the=20 counter-clockwise end and about 90% from wiper to the clockwise=20 end. A reverse-taper audio pot will have the counter-clockwise and=20 clockwise ends swapped. (An audio-taper pot is about 20dB down from=20 max when the wiper is at the center (50%) position.) As Bob has mentioned, there is a good chance that they are using=20 something like a lamp dimmer pot. In that case, just pull the pot=20 from a lamp dimmer and use that as your replacement. FWIW - I often rejuvenate pots by disassembling them and moving the=20 wiper so that it contacts a different part of the track. Add just a=20 touch of silicone grease to both the shaft and the carbon track. Not=20 much grease - just a tiny amount. dwayne --=20 Dwayne Reid Trinity Electronics Systems Ltd Edmonton, AB, CANADA (780) 489-3199 voice (780) 487-6397 fax www.trinity-electronics.com Custom Electronics Design and Manufacturing --=20 http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .