11 Jan
2013
11 Jan
'13
7:08 a.m.
-----Oorspronkelijk bericht-----
Van: cctalk-bounces at classiccmp.org [mailto:cctalk-bounces at classiccmp.org]
Namens tony duell
Verzonden: vrijdag 11 januari 2013 9:10
Aan: General Discussion: On-Topic and Off-Topic Posts
Onderwerp: RE: HP 9865A Cassette Memory service manual?
Youy may have noticed that I have been absent for a while. The reason is
that
my home internet access is down, due to problems at
the ISP end (I think).
I am
reading this in an internet cafe...
articles
Picked up a very dirty but nearly entirely
functional HP 9810A
recently, with 9865ACassette Memory drive. While I wait for parts to
repair the 9810's mag card reader and printer to arrive, I've been
working on cleaning up the9865A.
Are you a member of HPCC? The reason I ask is that I wrote a series of for the HPCC magazine on repairing this series of
machines, and you might
find
them interesting. I would offer to send them to you,
but of course there's
no
real way to transfer them at the moment.
They're
It is almost working (and the few rubber parts in it seem to be good)
--
I would strongly recomend replacing the 2 'tyres' on the drive wheels.
size 119 O-rings IIRC, and are not hard to get.
service
however it will not move the tape forward. There
are two solenoids
that control the direction of the tape and one of them (for the
forward
direction) is not activating. It shouldn't betoo difficult to trace
down the circuit and find the faulty part but before I dig too deep I
thought I'd see if anyone has a service manual for this thing. I've
looked in the usual places on the 'net and haven't found anything,
aside from Tony's notes for the interface.
I believe that some of the boards in the internal tape controller of the
HP9830 are the same (or at least very similar) to those in the
HP9865 -- at least they have 09865-xxxxx part numbers. The official HP manual covers the controller to component level, and
of course there are
my
schematics for the HP9830.
You can download the HP 9830 service manual at the Australian HPmuseum
website.
Most boards used in the 9865 are the same as in the HP 9830, I know for
sure.
The only boards that differ are the interface logics and the tape drive
board with the head amplifiers on it.
I suppose you looked at the pictures I made from one of mine on flickr,
http://www.flickr.com/photos/hp-fix/sets/72157630819381098/
After you checked the motor drive board, look at the IO card (A61) because
that board contains some 7403 's U1 and U3 which have a tendency to fail.
If this board fails you get errors which seems to point to other components,
so it should be check before you look at other boards.
The manual is very handy when looking for problems, you can find there a
description of all the signals with fault indications.
But also check the interface card, that also can be a pain in the ass (you
should ask Tony friendly if I may send you the diagram of the interface).
You also should look at the LDR from the tape sensor next to the head, they
have a tendency to go to a high resistance > 1k.
The result of that is no fast forward winding because the sensor never
'detects' the darkening of the tape.
I think the board you want to be looking at (and I am
doing this from
memory) is
the 09865-66564. There's a little logic and a
couple of transistors to
drive the
solenoids.
I assume the solenoid isn't burnt out ...
Not likely..
-Rik