Hello
I've bought a used, defective HP42S. It turns out that it works, sort of. It passes the automatic self-test, but fails with the keyboard manual self-test:
Sigma+ register STO,
1/X registers RCL,
CLX registers TAN,
ENTER registers ENTER followed by RCL,
X<>Y registers Rdown,
+/- registers SIN,
etc etc etc.
All keys have a good pressing feeling; the machine has a lot of dirt underneath the keys. I'd like to know if the keyboard is easily fixable, if its worth opening the machine to fix it. I'd also like to know how to clean the keyboard bezel: i've tried once with a thin slice of a plastic rubber, but it creates a lot of dirt in the process..
Best regards
Iuri