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Old 10-19-2016, 11:24 AM
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Robert Grant Robert Grant is offline
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Join Date: Feb 2008
Location: Monroe County, MI
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Quote:
Originally Posted by Ed in Tx View Post
Definitely looks like 60 Hz AC related. I notice a band of the interference takes about 17 seconds to go up the screen and start over at the bottom.
Yes.

The noise burst creeps upward because the field rate was changed to accommodate NTSC compatible color television.

NTSC sends about 59.94 frames/second, but our utilities still use 60.00, the motion is a result of the difference

(1) over (60.00 - 59.94) = 16.666.... seconds.
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