HP 97 Keyboard issue

[teenix]

(01-19-2020 08:15 PM)wmax351 Wrote:  I have been working on repairing an HP 97 I rescued from electronics recycling for a bit now.

In the past, it had worked, however, the keyboard has started not responding to anything entered on the right side (with the numbers). The left side, with the functions, appears to work well.

What should my next step be? I might also just part it out on the forum/ebay if there isn't a fix.

I cant see any logical reason why that side of the keyboard would have failed. The key circuitry is intermingled with those on the left side.

Do any of these keys work?
Have any failed on the left side?
Do they work in program mode?

There might be corrosion on the keys circuit board or on the connecting pins between the keyboard and CPU board.
Someone spilt coffee on the side of the board at some time and the keys there need cleaning.

Search for the HP-97 service manual on the web. It might help.

cheers

Tony