27 Apr
2012
27 Apr
'12
11:48 a.m.
I have an
HP9836CU (series 9000/200) without monitor cable.
I know it well.... That is correct. One of the pins on the DA15
connecotr on the
comptuer is
a 12V power ouptu. On the 9836A, it powers the monochtrome
monitor. On
the 9836C, it operate s a relay (actually a pair of relaus, for soem
unknown reaosn) on the monitor PSU board, whcih conenct maisn
to the rest
fo the SMPSU.
This is the mistake :) I was surprise to not hear the classic "sound" of
the high voltage on the crt tube, or the degauss coil "bump". It is pin-pin, I can't remembr if all pins
are used (but read
on...). I
am pretty sure it was special cable, the 3 video signals were
wires with
(75 ohm?) coax, the other signals with just palin wires, Oh, and an
I've built the cable, referring to the pinout in the manual. Some signal have a separate ground return; for them I've used
twisted wires (I was
at home , not in laboratory and haven't coax cables).
It work :) and the characters on the screen are very goog, withoud noise
or other defect. The cable is without shield, but the lenght is very
short. In the future, I can build a serious cable :)
Good!. Do you get any errors in the power-on self test>? Does it find the
graphics board and 2 floppy drives? How much memory do you have, and do
you have any i/O cards?
Any -U model is goign to have a bootROM 4.0 I think, which means you can
boot from an HPIB disk drive (floppy or hard), EPROM board, bubble memory
board, or whatever.
There should be a set of my schematics o nthe
same site. They
may well be
under the HP9826, the 2 machines are closely related so I
preodcued one
set of diagrams to cover the lot. Said diagrams cover the 9826, 9836A
(mono) and 9836C (colour) machines and monitors, and all the
CPU boards
I've seen, including the 68010 + MMU board in mu 9836CU.
I've found it and downloaded. It's a very big work !