Re: Apple2 to PC VGA monitor

[supertimer@aol.com (Supertimer)]

pausch@saafNOSPAM.se (Paul Schlyter) wrote:

>tarage  <tarage@bellsouth.net> wrote:
> 
>> Uhm, are you sure that it's at the right frequency? I seem to recall that
>> VGA and Apple ][ monitors were different frequencies (31.5 hz for the
>> VGA, and 15 something for the ][)....
> 
>You mean kHz, don't you?
> 
>Yes, you're right.  You would rather want a CGA monitor (with an
>input for composite video) to connect to the Apple II, since the
>Apple II delivers a standard composite video output signal (525-line
>or 625-line depending on how you strap hte motherboard.  If it's
>strapped for 525 lines you'll get NTSC color as well; if strapped for
>625 lines you'll only get black-and-white, unless you've plugged in a
>PAL card).

For the Apple II, CGA is just about right.  I had a Laser 128,
a IIe clone, that had a CGA connector.  However, CGA had
fixed colors that did not match the standard Apple II double
hires 16 colors so graphics looked bad.

For the Apple IIGS, CGA will not do at all.  The IIGS needs
analog RGB because it has a palette of 4096 colors and
can display up to 3200 of them at once.

The IIGS also has composite output, but because of the
limits of composite (NTSC in my case), the output is far
more blurry than the analog RGB output.  Here are my
test results:

Apple IIGS to standard Apple IIGS analog RGB: clear
Apple IIGS to monochrome composite (NTSC): clear
Apple IIGS to color composite (NTSC): blurry
Apple IIGS w/Second Sight to SVGA: clear
Apple IIGS to color composite out to PC composite
     input for display to PC SVGA: blurry

This proves that it is the limitation of the composite
output bandwith that is the problem.  The last test I
did was composite out to the video input of my PC,
by the way.