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Old 03-28-2018, 11:02 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 NewVista View Post
Do you think Argentina, Brazil, being what they are, might have been open to a discreet bribe or two... thus leading to those bastardized systems?
Well, there are other reasons to consider before one comes to the conclusion that a few billion Cruzandos changed under the table.

Brazil used and still uses 60Hz utility power, so they logically used the 525-line, 60-field USA system. Like all of the Americas*, channels had/have 6MHz total bandwidth each, hence SECAM or PAL B, D, G or K were off the table. Brazil went color far later than the USA did. Whether their decision was done to reject American dominance or simply to throw away that pesky hue knob may never be known.

Argentina and Uruguay were another matter. The had/have 50Hz power. They used System N, with 625 lines at 50 fields (25 frames) per second. Like Brazil, they only started using color when the PAL system was well established, and no country ever made a standard of NTSC and 50 fields, so PAL must have seemed a logical choice.

*Excluding some Caribbean Islands that used 50-field systems from their parent countries, all either low power or cable only.
Mexico experimented with System N monochrome. A TV DXer showed me a photo of an ID slide from XEFB-TV (then channel 3), Monterrey NL. Below the call sign, it said: "Nuestra siguiente programa se ve mejor en un Phillips". This DXer told me he lost vertical hold the instant the slide was replaced by the program.

System M and system N had very closely matched matched line rates (15750 versus 15625), thus horizontal sync was no problem. It is also true that one system's vertical rate may be compensated to the other with adjustment of the vertical hold, size and linearity controls. However, having the field rate match the power supply frequency is still desirable.
I own an ATSC converter box that offers PAL B/G video output (along with 480i, 480p, 720p and 1080i).
When I fed its PAL output to my 1958 Emerson TV, the picture was sharper but with more flicker, as I expected. However, the picture wobbled in a cycle- the picture looked like an image atop a shaking bowl of jelly. My suspicion is that a 60Hz magnetic field from within my home (possibly the autotransformer power supply of the television itself) was interacting with the 50Hz field of the vertical yoke.

Last edited by Robert Grant; 03-28-2018 at 02:29 PM.
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