I made my WP-34S (30b) usable!

[Dave Britten]

You've probably seen me and several others gripe about the 30b keyboard quality, and how it's the weak point of the otherwise excellent WP-34S. Mine had a number of reluctant keys, which made me reluctant to use it for "real work". Well, figuring I had nothing to lose, I tore mine apart and did some cleaning.

It's the typical "adhesive laminate layer with a bunch of metal domes" keyboard design. What I did was peel up the laminate from the bottom, stopping halfway (just above the XEQ row). Then I used a cotton swab dampened with 91% isopropyl alcohol (i.e. what I happened to have sitting on my desk) and scrubbed the metal contacts on the PCB. After that, I did the same with the dry end of the swab to mop up. Then I dampened another swab, making sure it wasn't dripping wet. I carefully scrubbed the inside of each metal dome, including the little "legs" at the corners. After letting them dry for a few moments, I visually inspected them for debris/residue, re-swabbing as needed until they looked clean (watch out for cotton fibers sticking to the laminate). I resealed the laminate to the PCB, then peeled from the top, repeating the procedure with the top 3 rows of keys.

After that, mine is working flawlessly, with all keys responding with no hesitation. I can probably get some actual use out of this thing now, though I suspect it's long overdue for a firmware update (gotta dig out my programming cable).