Front buttons on recent Keysight, Keithley equipment stop working

[maxwell3e10]

I have several pieces of fairly recent A-brand equipment (eg. Keithley 7510, Keysight B2962) where many front buttons don't respond unless pressed very hard or don't respond at all. They all were kept in normal lab environment. Beyond the typical rant about how new equipment doesn't last as long as 20-50 year old stuff, have other people experienced this problem? What is the recommended contact cleaning procedure?

[jjoonathan]

Yeah, I obtained a gunked up DMM7510 for "cheap" due to this problem. Here is the cleaning procedure. It works, but it is a pain in the butt. Hopefully less so if you know what to expect.

https://youtu.be/PLhyBDveVxI?t=288

[maxwell3e10]

Thanks for the video link! It's insane how hard it is to open, I guess they expect you to just pay >$1k to replace the whole panel. I wonder if the adhesive is the source of contamination on the contact pads. I didn't actually see in the video, how did you clean them?

[jjoonathan]

Adhesive migration (or some volatile component of the adhesive) would be my guess as well. I cleaned the old adhesive off the rubber and circuit board with kimwipes, rubbing alcohol, and patience. I didn't do anything to the button pads (pcb side and conductive polymer side) except scrub them down with kimwipes and alcohol and verify that this improved responsiveness as measured by a multimeter with fast beeper. Getting rid of the bulk adhesive was the least fun part of the process. Best of luck with it all -- the one good thing to come out of this is that in the end the cleaning procedure worked and the buttons are still responsive years later