01-17-2022, 04:03 AM
I'm seeing some technical misunderstanding going on.
1) NTSC standards are 59.97Hz for the vertical (interlaced traces makes ~30fps) and 15736Hz for the horizontal. This frequency was chosen because it was in sync with the 3.579545 color burst.
The author is using a super cheap basic matrix generator which syncs to both of these. It uses TTL dividers and square waves to reproduce the basic dot/crosshatch patters using different pulse widths. The color it generates by sending a burst pulse.
It's the generator he's using that you're seeing as out of sync/frequency vertical/horizontal. It's actually in sync, but there is some h-k leakage going on, mostly capacitive. My first suspicion could still hold true, and there is a problem with the long cable going between the chassis and CRT.
1) NTSC standards are 59.97Hz for the vertical (interlaced traces makes ~30fps) and 15736Hz for the horizontal. This frequency was chosen because it was in sync with the 3.579545 color burst.
The author is using a super cheap basic matrix generator which syncs to both of these. It uses TTL dividers and square waves to reproduce the basic dot/crosshatch patters using different pulse widths. The color it generates by sending a burst pulse.
It's the generator he's using that you're seeing as out of sync/frequency vertical/horizontal. It's actually in sync, but there is some h-k leakage going on, mostly capacitive. My first suspicion could still hold true, and there is a problem with the long cable going between the chassis and CRT.
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