grent@comcast.net wrote:
Polymorph wrote:As an update to the story, I did some more testing last night and it would seem that the pots are still operational (yay!). It is the connection from the resistive material to the terminals (correct terminology? the things the wires are soldered to) that is a bit dodgy. If I apply pressure to the contacts (ie. push them onto the resistive material, I get fairly good readings from both pots. One gets the full range of 0-255, the other 0-222. The second pot may require further cleaning (and yes I will stick with contact cleaner from now on!). I am thinking that if I apply a little solder between the terminals and the resistive material to improve the connection, the joystick might be operational once more. Maybe the WD-40 didn't kill the pots, but somehow reduced the conductivity around the terminals?? Does this sound likely, and does my proposed solution sound feasible? thanks, -pI do not think that soldering will add any more contact or better conection to resistant material. But It should not hurt. But if that connect is loose or high resistance, then there is a problem. Not sure how the connection is made to the terminal. May just crimped or riveted to the carbon pad. Just not sure. If soldering make a better connection by making tigher then it should help. You might be pushing on the resistive material and making a better connection on the wiper contact. Solder and clean the pots and see what happens. Still may have WD40 resedue left.
Agreed. The usual method of connection is riveting/crimping, and an intermittent connection (end-to-end) is a sign of a cracked resistance element--often right at one end. If the end-to-end resistance is stable and close to specs, then the element is probably fine. If the end-to-wiper resistance is unstable, then the pot is dirty or worn, or the moving contact has lost its springiness. -michael New, faster SUDOKU v2.0 solver for Apple II's! Home page: http://members.aol.com/MJMahon/ "The wastebasket is our most important design tool--and it's seriously underused."