-----Original Message-----
From: cctalk-bounces at
classiccmp.org [mailto:cctalk-
bounces at
classiccmp.org] On Behalf Of Tony Duell
Sent: 21 November 2013 20:01
To: cctalk at
classiccmp.org
Subject: Re: HP-150 Touchscreen
At last a machine that I have heard of...
I guessed you might be interested in this one as I know you are interested
in HP. I used to use some 300 and 800 series machines back in the late 80's,
I got on well with those machines. But I still like my DEC machines.
> I have just collected one of these machines. I don't know a lot about
them.
It seems they
use a customized version of MS-DOS. Does anyone have a
copy?
Whcih amchiendo you have? The original HP150, or the later HP150-II? The
obvious external differnces are :
HP150 (Original) :
9" CRT fixed in the case
2 expasnion slots, the boards go in from the back of the machine HPIB and
2
serial conenctors on the back Power swtich, brightnes
and focus (!)
controls
on the back Keyboard conencted by a 6p6c
'modular' plug External clip-in
battery holder on the back Can take an internal thermal printer
It is the original one then, it has the 9" monitor.
HP150-II
12" CRT in a tile mounting
4 expansion slots, boarfs go in from the top HPIB and 2 serial conencotrs
bekind the clip-on back cover. Plugs go in from the top Power switch is a
button on the front under the CRT Brightness control is a knob on the left
side (IIRC).
Keyboard conencts via an HP-HIL connector No exernal battery holder.
No intenral printer option
I will assume from the fact you've inspected the pSU that you have the
original machine. THat one is a lot easier to dismantle to get to the PSU.
>
>
>
> I have inspected the PSU in the base unit and there are no obviously
> swollen capacitors, but it is 30 years old. Not sure if I should try
applying
power.
If this is the original version, the top case comes off with 2
quarter-turn
fasteners on the bac. If you have the printer,
it's best to take tht out
first.
With the top case free, unplug the fan fro mteh PSU
board, do not forget
to
reconnect it.
You are talking about the monitor PSU, I have only opened up the base unit
so far, which is a 9121 and which I think is what you are referring to as
the external disk unit. I think I may have misunderstood what I have. I will
take a look at all the things you mention below.
Thanks
Rob
You wil lthen see 2 PCBS, one id the video montiro,
the otehr is the PSU.
It is obvious which is which. On the PSU board there are 2 large
capactiros
almost i nthe middle. These are hte mains smoothing
capacitors. And they
are just postioned right that if they decide ot burst they will break the
neck
of the CRT. So do inspect those carefully.
The next trick is how to get to the logic boards. This is nto at all
obvious. You
can remvoe the tope cover if you wnat to, you
don't have to.
First unclip the battery holdre from the back of the machine. It contains
2 N-size cells ('Lady' size, LR1, etc). These are 1.5V each. Do _NOT_ put
in the
similar-sized 12V batteries used for soem car keys,
etc. THey will wreck
the
real-time clock IC.
Take out the expanison boards if you have any. There are 2 thumbscrews on
the card reap plate, undo thoese evenly and the board slides out.
Next unscrew the jackposts on the serial connectors (3/16" A/F) and the
HPIB connector (9/32 A/F). Then remove the 5 screws on the cardcage rear
panel and take that off.
Inside yoy wil lsee the video board at the top of the cardcage. It comes
out
easily. TThe processor bord assembly coms out too. It
has 2 daughterboards
('Mezzanine boards' in the HP manuals), one cotnains the memory (ROM and
RAM) the other contains some of the serial port circuitry.
Most machines have 256K on the memory board. I think there was a 128K
version. Thers is a very cxommon expansion bord to ad 384K, bring the
memroy up the the full 640K. There is a similar board that adds and HP-HIL
port too. This lets you plug in a mouse.
Others have mentioeed the Australian museum site as a source of manuals
nad disk images. One manual that doesn't seme to be there, and which is
very useful, is the Technicla Reference. This isn't quite as good as the
IBM
TechRef in that it doens't include the ROM
sources, but it does contain
all the
BIOS calls (ntoe, the machiens is neither hardware not
BIOS compatible wit
hthe IBM PC) and the schrmatics of most of it apart from the PSU. I ahve
this
on paper (including the HP150-II updates), but it is
fr too think to copy.
What (if any) disk unit(s) do you have? THere is, of course, no internal
disk on
the HP150, you have to use an external HPIB unit.
When you power it up, nothign wil lappear on the screen for quite some
time. There are some LEDs on one of the boards, visible through a slot on
the
back, those should display changing patterns. At least
that will indicate
the
PCU is running.
-tony