Re: Apple RGB monitor

[shack@onyx.southwind.net (Randy Shackelford)]

Mitchell Spector (spec@vax2.concordia.ca) wrote:

[snip]

:     Generally speaking it is not compatible with any Macintosh, due
: to the fact the horizontial scanning frequency is incompatible (the
: AppleColor RGB works at 15.75 kHz--NTSC rate, compared with 30+ kHz
: used and required by the Macintosh and PC's with VGA/SVGA output).

:     There is a rare exception, if you have the 'High Resolution
: Display Video Card' (Apple part no. 820-0185) it will connect
: directly to the monitor and adjust its frequency to match. This
: card works only in NuBus slotted Macintoshes, so that leaves you
: with support for mostly the Macintosh II line. Even so, I would

Actually there are plenty of Quadras, Performas, and early Pmacs using
nubus too. The card is the normal Apple 8 bit video card and wouldn't
be overly rare I would think.

: recommend against this option for a couple of reasons: 1) The dot
: pitch is quite low (0.37mm) which will make things appear a bit
: blurry and difficult to make out detail. 2) You have to operate
: it in interlaced mode, meaning it will flicker noticably and will
: cause eye strain in a few short minutes or less. 3) The maximum
: resolution it supports, in interlace, is 640x400. Most Macs use
: a slightly higher vertical resolution, meaning part of the image
: will get chopped off. 4) The maximum refresh rate supported is

You sure about that? Normally Macs can determine the resolution of their
displays via sense codes. 

: 60 Hz, which causes more eye strain because it flickers out of
: the corner of your eye and is more glaring (this may not affect 
: you though, it is _very_ common for Macs to use low refresh rates 
: like 67 Hz, which also flickers but I guess Mac users are able
: to deal with it. People outside N.A. deal with 50 Hz...yikes! :).

:     Bottom line--unless you have a NuBus slotted Macintosh and
: that above video card (and don't mind if your display is blurry,
: partly cut and potentially causes eye-strain and headaces) then
: your better off finding a modern display, or at least one made
: for the Macintosh. :-) You can use a PC SVGA display, with a
: small and fairly inexpensive (sometimes free) video adapter as
: well, which gives you a wider option for picking monitors.

I got a secondhand NTSC nubus card which I use in my IIx. That's a bit
blurry on a composite color monitor but usable. You could use a less than
optimal display for some things such as running a file server.
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