Yes carbon based keypads will do this after a while. Here are some tips i have heard of for "re-juicing" the contacts.
My big complaint with the 500 has been the exact major issue this web site pointed out years ago when this remote was first reviewed ...... the center joystick "select" button ..... added a drop of epoxy under the keypad .... much improved.
KC
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take a number two pencil and scribble onto a piece of paper, take the eraser and get the graphite you just scribbled onto the eraser tip (erase "lightly" to do this.) now apply from the eraser a thin coating to all the button contacts. this should make a huge difference.
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The conductive pads on some keypads are silicone rubber with a high content of a specific carbon black (Shawingan) to make them conductive. Unfortunately all carbon blacks contain sulfur which causes the cure (crosslinking) of the silicone polymer to be inhibited. The uncrosslinked polymer will eventually bleed to the surface causing the pad to become non conductive. This a problem for all silicone keypads except where silver is used in place of carbon black (military, aerospace, etc)...in these applications part cost is not critical.
Clean the carbon black pads (and the trace contacts on the pcb) with isopropyl alcohol. If the pcb contacts have oxidized use a pencil eraser to clean them and follow up with the ipa. You can improve keypad reponse by coating the carbon pads with a layer of silicone containing silver. A kit is available from Chemtronics (p/n CW2605 about $12). It works very well and one kit can do several keypads. It has a very short working time after mixing...so gather all your controls (tv, radio, Autostars, etc) and do them at the same time.
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Last edited by kcaudle
on November 25, 2007 22:01.
