10 Jul
2014
10 Jul
'14
2:05 p.m.
The original PC was definitely capacitive, I have
taken them apart to
clean them and I believe the 84 key AT keyboard was capacitive too, but
Agreed. I've had them totally aparttoo (well, I _would_). I've also had
a tyype M totally apart (to the point of cutting off the heat stakes
(they were replaed with small nuts and bolts) and taking the flaps and
membrane layers out. The one I worked on was certainyl a membran contact,
not capacitive.
I am not positive and the AT tech ref does not say.
The keyboard
I was going to suggest looking at the schematics in the AT TechRef, and
then I rmmembered that for oome odd reason the only scheamtic fro the 84
key keyobaard is the one for the little LED PCB. The keybaord itself is
not there.
I have the 84 key keybaord somewhere, bot not to hand, or I'd open it up.
The sens amplifier chip i nthe capcitive units is one of those square IBM
metal cans, it's very distinctive.
-tony