|HP 9826A key switches|
Message #1 Posted by David Ramsey on 3 Jan 2012, 10:22 p.m.
I've come into possession of a 9826A controller, the red-headed stepchild of HP collectors.
It was free, and has 2.7MB of memory.
I installed a TAS-obtained BASIC 2.0 card. It took me a while to figure out how to use it, 'cause the manual says with a ROM BASIC card it will simply come up automatically and say READY, but in reality it displays "ROM: B B" at the upper right hand corner of the screen and you have to press "B". But I digress...
Several of the keys on the keyboard don't register. Checking with a multimeter, I can see that pressing a working key shorts the corresponding switch's two contacts on the bottom of the keyboard PCB, whereas pressing a non-working key does not. OK, so the problem is the key switch.
The dead keys are really dead and will not register no matter how hard I bang on them.
Physically, the 9826A key switches look very like modern key switches. They snap into a metal support plate and have two solder points on the keyboard PCB.
So: any suggestions as to my options? Is removing a key switch and trying to disassemble and clean it reasonable? Should I look for a parts machine?