24 May
2007
24 May
'07
11:22 p.m.
I've actually fixed one of the CIT-220+ keyboards. It's *not* a job for the
faint of heart. It requires desoldering all 130-odd keys (this REQUIRES
a GOOD
$250 desoldering iron, lacking this I paid someone $60 to do it for me),
prying
each key apart with two sewing-pins, pulling the contact out and
scouring out
the crap in between the little contact pads using a pin, and bending the
sensor-push plate/spring back into an L shape so the key gets good
sensitivity.
The keyboard I had required this because someone at my university had
spilled
something (milk perhaps?) into it and it wicked up into about half the
keys and
got between the metal sensor plates. (The metal sensor plates are the C.Itoh
cheap alternative to any DECENT type of keyboard key mechanism such as
one the
IBM model M clicky keyboard used. I also strongly suspect the real DEC
vt-220
and vt-330 used better technology but I've never seen a real DEC one. :( )
I'm on the lookout for a C.Itoh CIT-220+ manual or a real DEC vt-330
(plus KB)
since I have the manual for a vt-330 and it looks far superior to the
CIT-220+.
I've also dumped all the ROMs from the CIT-220+ if anyone wants/needs a
copy.
(IIRC it uses an 8085 plus two GFX chips plus RAM plus EEPROM plus a bunch
of logic chips in the main unit, and an 8032 or 8048 in the keyboard.)
I could also scan the VT-330 manual if needed, though it will take a while.
Jonathan Gevaryahu
jzg22 at drexel.edu