19 Sep
2011
19 Sep
'11
2:14 p.m.
Hi guys,
I just picked up a Motorola M1000-355 CRT monitor (5in diagonal
open-frame industrial "thing", circa Jan 1987 so almost as old as I am!)
at the hamfest today.. Problem is, I don't have a suitable mating
connector for the card edge connector...
It's a 10-pin single-row card edge connector, with a 0.156in pin pitch,
although I suspect a dual-row (20 pins total, 10x2 layout) would work
fine too.
Normally will, You can either ignore the other row of terminals, or
solder the wires to the corresponding pins on both sides.
These are listed as "US stock only" or "Discontinued, obsolete" by
every
supplier I've tried... Does anyone have one squirrelled away in a box
somewhere which I could buy or have (he says with a cheeky grin) ?
Have you treid Digikey? 0.156" edge conectors are not common in the UK,
but they are common in thr States. I've needed such connectors (and
indeed 0.125" pitch ones) to repair old HP desktop machines and Digikey
have always had something that will do (if not the exact part). They will
ship to England, the only downside is the shipping chages.
You mihht find one somthing with this few contacts that a 0.15" pitch
connector will work. They're more common in the UK, but only on older
stuff. I don't think anyone still sells them.
There is a klduge if you don't mind modifying the monitor. 0.156" headr
plugs and sockets are not hard to find. You cna solder a header to the
monitor PCB (either 'SMD' on the edge, solderign the pins of the header
ot the edge figners, or drill holes through the fingers and fit the
header conventionally). Personally, I'd get the right connectr.
Or possibly a lead on a source for one or two of these, ideally with
keypins (but the latter isn't essential)?
I'd also rather like a copy of the datasheet for the monitor module if
anyone has it... I have a pinout (it's the standard 10pin pinout as
posted by Tony Duell quite a while ago -- IIRC either the Kaypro or
Many, many 'cahssis monitors' use this pinout. It's a defacto standard
IMHO. IIRC the TRS-80 M3 and M4 monitor PCBs have the same pinout.
Osborne monitor uses the same pinout) and a sneaking
suspicion that it's
CGA-spec, but no hard proof.
I doube very much it's colour :-). But I agree, it's likely to be TV
rates (you'll be able to get it to work with either British or American
frequencies by twiddling the presets, I susepct).
I suspect for somethggn that old they'll have been a proper service sheet
-- I have an old British terminal (old meaning that the video is held in
shift registers, and the keyboard is upper-case only, with mods in the
mnaul to enable lower case) which has a compoiste Motorola open-frame
monitor in it. The manual for the terminal includes the Motorola service
manual for the monitor.
I do know that it pulls 12V DC at about an amp -- the
first value is
printed on the PCB, the second was provided by the meter on my bench supply!
Be careful. It's not unheard-of for such monitors to have no horizontal
oscilaltor, so if you're not feeding them an Hsync (realy Hdrive) signal,
the horizotnal output stage is not doing anyting. You may find the supply
current increeases when you actually gett it working. If you know you had
EHT, then the horizontal output was working, of course.
A couple of points on that. Firstly, if the EHT is present and you have
nothign on the scrreen (no bream current), the CRT is quite likely to
remain charged when you remove power. Be careful if you disconnect the
anode cap. Seondly, a neon bulb (NE2 or similar), or a mains tester
screwdriver will often glow if you hold it near an operatin flyback
transformer (don't cnnect it to anything).
-tony