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Old 10-21-2022, 04:51 PM
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old_tv_nut old_tv_nut is offline
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The game console problem was due to the games using non-NTSC-standard scan rates (often 262 line/60 progressive) along with non-standard sync waveforms. Zenith had just introduced a sync detection/count-down chip that looked for the full NTSC vertical sync pattern and locked so well on over-the-air signals that the signal could be so weak that you couldn't recognize the picture, yet the vertical and horizontal were perfectly stable and no hold controls were required. They had to modify the design to detect non-standard sync and default back to separate H and V detection in that case.

I don't remember if there was a fix *in the TV* for these earliest chipsets with countdown or not.

Here's a previous thread that said the game makers offered a fix, but also mentions some TVs with a jumper that could be changed:
http://videokarma.org/showthread.php...h+sync+problem
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