5 Aug
1998
5 Aug
'98
8:35 a.m.
On 4 Aug 98 at 18:45, Tony Duell wrote:
No, I was thinking more about interfacing. What works with what computer.
The differences between formats. MGA, CGA, EGA, VGA, SVGA,
RGB, Composite, TTL <> Analogue, V-H refresh rates, etc.
Then there's the plugs and cables. Coming from an Atari-C64 background it
took me a while to recognize that a 9pin dbl was likely not a VGA , but not
always as with the multi-synchs. Most monitors don't say on the back what
they are ,or even if they are color or not. Then there are the 15pin DBL(?)
DEC and 3270 plugs not to mention the various DIN plugs. I've only
recently found a good diagram of the various shells (from the Redmond Cable
site) How about changing a 9pin multi to a 15-pin ( 3rows).
Macs and Apples have their own quirks. Certainly the info is out there at the
various platform sites or in their manuals, but not always. SVGA is another
ball of wax entirely. I have monitors that I'm not sure whether or not they're
SVGA capable, not to mention how the FPD flippables work. Radius has
nothing on the older models that I could find. It's a complete subject in
itself and especially for collectors or those with older machines.
Unfortunately
I know little about monitors. Is there a good source for info on
What do you want to know? If it's about repairing them, then I've found
the best references to be the 2 volumes of Mauritron Computer Monitor
Circuits that were published on paper (the CD-ROM versions are nowhere
near as useful). Each book costs about \pounds 50.00, and includes about
50 monitor circuit diagrams. Even if the monitor you have isn't
included, you'll probably find a circuit fragment which matches the one
you're working on.
That's why the book is a lot more use than the
CD-ROM. It's a lot easier
to flip through the book.
I'd agree there, but at 100 Lbs.($300 Can ?) for the two I'll settle for
the
inconvenience of the CD.
I also have a few monitor service manuals. Some of
them I have because I
have the monitor, others because they contain 'generic' circuits that are
used all over the place.
Also, of course, books on TV servicing are useful.
If you want info on using the monitors, then I can't think of anything.
In my experience the customer controls and connections are pretty obvious
(or can be obviously traced if you pull the cover).
Well this Taxan I've found has as well as the color<>mono
TTL<>Analogue
sitches and the usual monitor/TV-type controls, 4x4 matrix preset controls, 3
p-b controls, Preset: Auto- release, Scan: Auto- Overscan, Mode: Auto-16
colors. Which is fairly self-evident, but without knowing the Video
characteristics of the computer you're hooking it up to, all could go up in
smoke. How much easier it would be to look it up in a book with references as
to matching monitor-computer. Even kind of a Dummys' Guide to monitors
for the neophyte.
I suppose all that's left is finding out what the
scan rates are. For old
single-frequency monitors, without those silly power-saving features,
the best way to find the horizontal scan rate (at least approximately) is
to power it up without sync, and look for the main frequency in the
random electromagnetic emissions. Sometimes just holding a scope probe or
counter probe near the monitor will do it. Sometimes a very loose
coupling to the flyback (a couple of turns round the core) will do it.
Vertical scan rates are a lot easier to modify, so those don't bother me
so much.
There are monitor specs available for those of us that don't have a scope or
the know-how to measure for them but it's pretty sparse. And of course
then there's the computer end of the problem.
If there isn't any such book available it might be a worthwhile project.
" Everything You Ever Wanted To Know About Monitors".
I'd certainly buy one.
-tony
ciao larry
lwalker(a)interlog.com