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Home Forums 68kMLA Power R Video Adapter — #27
Post #27 by Mac128
Source Forum68kMLA
CategoryHardware
Post DateSat, 23 Aug 2008 - 18:46
Original URLhttps://68kmla.org/bb/threads/power-r-video-adapter.14485/
Post
So, let me put my thoughts out there. Based on everyone's input above:

If the Compact Mac horiz. sync rate is 22 KHz and even minor deviations will cause the monitor to fail and monitor manufacturers adapted their existing monitors to create custom Power R video adapter Mac versions, why then does the Power R use the unique 22.3 KHz? Did that ensure compatibility with only custom Mac specific monitors designed to work with it and no other adapters (Like a home-brew 22 KHz TTL)? I mean if the industry standard Max EGA horiz. sync rate was 21.8 KHz and the Mac was 22 KHz, if the Power R could increase the rate to 22.3, couldn't it have come down to the industry standard too? Clearly, those adapters designed to display the Mac image on a standard TV had to drop the rate down into the 15.7 KHz video signal.

Which brings me to another question: Do CGA & EGA both require a specific pixel resolution, meaning a 512 horiz. resolution can never be displayed on a CGA or EGA monitor which require 640 pixels across? Also, just what is a TTL monitor? Is this different from and MDA or Hercules based monitor? How can these monitors display graphics at all if they have no pixel control? How can they accommodate a Mac signal at all if they are designed to display a significantly wider horiz. image than the Mac?

More brain-ticklers to come.

mp.ls