23 May
2010
23 May
'10
10:19 a.m.
Though isn't SECAM essentially PAL but with the
colour encoded slightly
That statement makes no sense to me at all.
PAL is a colour encoding method. SECAM is a totally different colour
encoding method.
So how SECAM can be essentially PAL with the colour encoded slightly
differneetly is beyond me.
I think I know what you are thinking. You are assuming that PAL video
signals are 625 lines interlaced, 50Hz vertical, And so are SECAM
signals. Well, AFAIK, that is not a _requirement_. It's certainly not a
requrirement for PAL (there are at least 2 525 line/60Hz PAL standards in
the lists I have).
differently. e.g. if you feed a SECAM signal to a PAL
display you get a
picture that is black and white.
If the scan rates are the same you probably would do. All the boradcast
colour systems are designed so that they are both-ways compaitble with
the related monochrome signal (a monochrome display will corectly display
a colour signal as a grey scale, a colour display will likewise display a
monochrome signal).
There are, I beleive, at least 2 versions of SECAM used too. Philips did
various decoder chips for these at one time, but my data books are 20
years old now, and I guess things have moved on...
-tony