Re: Odd //c monitor

[mjmahon@aol.com (Michael J. Mahon)]

Bill Garber wrote:

><exegete@nunya.biz> wrote in message
>412d6dd1_5@corp.newsgroups.com">news:412d6dd1_5@corp.newsgroups.com...
>:
>: Bill Garber wrote:

<snip>

>: > For God's sake, it says "Apple Monochrome Monitor" right on
>the
>: > back in one of the pics, and you can see the composite RCA
>cable
>: > running from it to the back of the computer.  :o)
>:
>: Yup! But, it's far crisper than either the Monitor II or ///!
>
>Agreed, but most grayscale monitors are. I have one that was used
>in Ultrasound machines at one time and although the portion of
>the
>screen used is small, it is crisp and clear. I now need to try
>some
>magnifiers to see if I can get it big enough. Makes a nice IIc
>display.

The sharpness of a monochrome monitor is limited only by its
focus (normally quite good) and the bandwidth of the video
source and amplifier.  (OK, another thing that can--rarely--
blur the display is a dirty, scratched, or diffuse faceplate.)

It is quite common for monochrome monitors to have 15MHz to
20MHz bandwidth, comparable to the bandwidth of the Apple II
video output.  This makes almost any monochrome monitor _very_
sharp compared to any dot-matrix color display, regardless of
mode.

BTW, the limiting bandwidth may not be achieved if the display
is overdriven (contrast too high).  The proper way to adjust a
monochrome display is to turn the brightness control up until
just below the point where the black parts of the raster begin to
be visible, then turn the contrast up to the lowest setting that
produces acceptable "brightness" in the white areas.  This
ensures that the video amplifier is not overdriven.

-michael

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