18 May
2005
18 May
'05
4:55 p.m.
I think I have the touchscreen frame from one of
those, 4 circuit
boards linked together in a box, with a lots of LEDs and
phototransistors. Always been curious what it came out of.
Quite possibly, that's how the touchscreen worked on the 150.
FWIW, I have the HP150 Technical manual, with the HP150-II update. It
includes a schematic for the original touchscreen, but not, for some odd
reason, the one used in the -II machine with the HP-HIL interface.
-tony