Repairing an hp 32sii

[John MacLean]

Can anyone offer any advice on how to repair a 32sii. The calculator works fine except the bottom row of keys (0 . R/S + ) don't work. I'd like to crack the case and clean it out to see if that would help but not sure how to do that.

John MacLean

[Jeremy]

If an entire row of keys isn't working, you might want to look for a severed trace on the circuit board. That would be my bet. It is unlikely, IMO, that dirty contacts would blast an entire row of buttons.

I recently disassembled and repaired a vintage Unisonic 888 calculator which I bought on eBay for $0. (Since it was not the one I won and since it didn't work 100%) Whoever had taken it apart before me didn't quite get the keypad back together properly, and I can see why. It was an absolute nightmare since each key had a spring, a contact bar, etc. Getting everything coordinated properly took a lot of patience, steady hands, some glue, and masking tape to hold the thing upside down while I worked on it. Anyway, good luck.

-Jeremy

[Randy Sloyer]

You'll find opening instructions here:

http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/articles.cgi?read=5

Once you open the unit, inspect the twist tabs that hold the logic board to the calculator. I'll bet you'll find the bottom left and center tab bent over or not twisted fully to the center. This will result in a loose connection directly underneath the logic board were the keyboard connects. The bottom row of keys is the forth from the left contact on the keyboard, right in the middle between the two twist tabs I mentioned. Pop the logic board off, clean with isopropyl alcohol (don't rub too hard) and reassemble starting with the bottom right and left tabs first. That centers the logic board on the frame. That should do for you.

I've seen the same problem on Pioneers that have been sat on, it smashes the retainers and the keyboard looses contact, resulting in dead rows or columns.

[John MacLean]

Thanks for your advice guys. That's exactly what I needed.

John MacLean