Monitor Synchronization - Zenith Z-100 Reference Manual

Monitor Synchronization

If you are using an RGB (color) monitor which requires composite (horizontal
and vertical) sync, position J303 to "C". If your monitor requires separate horizontal
and vertical sync, position J303 to "V'.
Position J305 to the video card markings corresponding to the vertical sync polarity
required by your monochrome monitor, positive "+ ", or negative "— ".
Position J306 to the markings corresponding to the horizontal sync polarity re-
quired by your RGB (color) monitor, "+" for positive sync, "—" for negative sync.
Position J307 to the markings corresponding to the vertical composite sync polarity
required by your RGB (color) monitor, positive "+ ", or negative "— ".
Video Graphics Programming
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