Sorry to bother you again on how to open an HP21, this was probably answered 1.22e44 times already here.
I got it from my hair cutter (seems everybody knows I'm a calculator nut).
The machine has dead batteries, + and - keys stuck, and the display flickers when on the charger alone.
I'd like to clean up the keyboard and test operation with AA batteries.
Any help would be appreciated.
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