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From: ISW@cup.portal.com (Isaac S Wingfield)
Newsgroups: sci.electronics
Subject: Re: NTSC-PAL (in)compatibility
Message-ID: <19790@cup.portal.com>
Date: 22 Jun 89 21:51:00 GMT
References: <124@nisca.ircc.ohio-state.edu> <11170019@hpfcdj.HP.COM>
Distribution: na
Organization: The Portal System (TM)
Lines: 19

As I remember, PAL stands for Phase Alternate Line, and does
just that. The 3.58 MHz color subcarrier flips phase by 180
deg after each line, and to recover the signal properly, the
receiver needs to have a 1-line (63 uSec) delay line which is
kicked in on alternate lines to straighten things out.

The (supposed) justification for this is to average out phase
errors incurred during the distribution of the signal. I believe
PAL sets have no "tint" control (everything's perfect; you don't
need it).

Interesting sidenote: despite all the "improvements" brought about
by PAL or secam, the best commercially broadcast stuff around
used to be (maybe still is) in Japan, where they use the old, kludgy
NTSC system invented here. They just pay attention to the adjustments
and keep it tweaked up real good.
(NTSC = "never twice same color")

Isaac    isw@cup.portal.com