Hi,
Just an update on my Lisa 2, i.e. the first machine I posted about. This is
the one I thought had the drive issue, but in fact simply needed a DD disk
in the slot rather than my HD one.
Anyway, today I managed to make two Macwork disks from Lisa images on the
web. My web machine is a PC so it involved using software called Transmac
and a Mac Classic 2 with a 800k drive attached which I could use to write
the 400K images.
Anyway, the good news is the Lisa booted just fine! However, the bad news
That is good news!
is (as I suspected) all THREE of my Lisa keyboards are
non-functional.
Well, not quite. One has the '4' key working on the keypad, the other has
the '/' key working. But that's it.
Well, that's no so bad either. The fact that one key works would seem to
indicate that the keypbard microcontroller (I am guessing it's a COP400
series Apple seemed to like them at this time) is working. And the rest
of the keyboard electronics is probably OK
I know there is a bit of info on the Web as to how these might be repaired
so it's off to have a look!....
IIRC, this is a Keytronics capacitive keyboard. Basically on the bottom
of eack key pluger is a dis of foam with a disk of metalised plastic
(metal side towards the foam) under it. When you press the key, the
mtalised plastic covers 2 pads on the PCB, increasing the capacitance
between them (the metal deoes not touch the PCB pads, the plasitc layer
is in the way). They suffer from 2 main faults. The foam dexays, and
sometimes the metalisation does too.
You need to dismantle it and have a look. Take off the outer casing first
(I ssume screws on the underside). if the keybaord cable is plugged into
the PCB, I'd unplug it to make thigns easier to handle. On the bottom of
the PCB,m under the keys, are lots of small screws. Take tne out (as a
matter of principle, I try to take them out in a diagonal pattern, but it
doesn;'t really matter here), and lift off the PCB. You can now see the
foam and disks, and hopefully see what;s wrong...
-tony