In message , Geoffrey S.
Mendelson writes
Martin Brown wrote:
The main difference seemed to be like with RIAA equalisation that the
Japanese engineers read the specification and implemented it fully where
as the US engineered version was "near enough" and cheaper.

PAL was more complex still but got around the inherent drift problems by
having phase alternate line so on average chroma drifts cancel out.

According to many postings here, NTSC originated the alternating line
phase shift.

It was not necessary in the US due to the difference in the way that
TV signals were disseminated off the air, e.g. between the studio and
the transmitter.

The problem with the odd color shifts, or lack of color stability in
the US was usually a problem between the camera and the transmitter
due to something not being properly adjusted.

Bear in mind that the US had NTSC on the street in the 1953,
the BBC did not broadcast in color at all until the end of 1967, and
regularly two years later.

So if there was any reason to adopt the phase alternating line color
sync (which there was in retrospect), the BBC had 14 years to figure it
out.

Wikipedia seems to give a pretty comprehensive account of the history of
NTSC etc.
http://en.wikipedia.org/wiki/NTSC
The later development of a colour system which compatible with the
existing monochrome transmissions was indeed ingenious.

The BBC officially launched their regular scheduled colour TV service in
1967.
http://news.bbc.co.uk/onthisday/hi/d...ewsid_2514000/
2514719.stm
However, they had been broadcasting various engineering and trade test
programmes (using the normal 625-line PAL) for some years. Prior to
that, they had been trying various colour systems and line standards
(including, I believe NTSC on 405-lines). However, despite the
politically shilly-shallying, it was pretty obvious that they were going
to end up with PAL.
--
Ian