http://www.ee.surrey.ac.uk/Contrib/WorldTV/broadcast.html
which is a pretty definitive reference.
Peter
Although the footer says that it was last updated in 1999 - which
might be why it doesn't show NC (or CN). ITU-R BT.470-6 was 1998 - but
I guess that folks meddled with it (or ignored it) afterwards.
This site does - where NC is presumably Combination N - and I've seen
elsewhere as PAL-CN
http://www.datapro.net/techinfo/PAL.html
--
Rgds
Paul Webster
That is odd - it shows the 4.43 625/50 PAL N standard as having 7.5 IRE
set-up - which is a very odd thing that most other PALs (and Japanese NTSC)
don't have... ?
Steve
I think it's genuine. World TV Standards websites all say that PAL-N is what
I thought it was, but when it comes to TV cards for the PC there is a
different concensus. I found three different sites with datasheets for
mutistandard video encoder chips (see links below), and these are quite
clear that there are 2 different versions of PAL-N.
Firstly, there is PAL-N, also described as PAL-N (Non-Argentina), which has
the same colour subcarrier as PAL-B,G,H,I that is 4.43361875 MHz.
Secondly there is PAL-NC, also described as PAL-Nc, PAL CN, PAL-N Combo,
PAL-N Combination, PAL-N (Argentina) which has a 3.58205625 MHz PAL
subcarrier.
It looks like Argentina uses the PAL-N system described on the World TV
Standards sites, but this system is now referred to as PAL-NC by the chip
manufacturers. It looks like Uruguay and Paraguay, the "PAL-N
(Non-Argentina)" countries do something different. Quite what this is is a
mystery.
They obviously can't use 4.43 MHz colour with 4.5 MHz sound, so they would
have to change the sound subcarrier to a higher frequency for terrestrial
broadcasts. But this seems highly unlikely since it would no longer be to
the System N standard, and the sound would be within the adjacent channel
causing severe interference on vision.
The only other thing I can think, since they evidently don't use PAL 3.58,
is that they have never introduced colour on terrestrial. Perhaps they only
broadcast in colour on cable or satellite and that uses PAL 4.43? I don't
know, but it looks like something is going on that's not quite in line with
the accepted list of World TV Standards.
http://www.cirrus.com/en/pubs/proDatasheet/DS278F2.pdf
http://www.electronics-lab.com/forum/attachments/SPCA711.pdf
http://www.globalunichip.com/spec/UECD-0001-DS.pdf
http://www.digit-life.com/articles2/radeon-tv-out/
It's probably one of those unofficial "non-standard standards" like "PAL-60"
or "NTSC-443" that is only used in closed-circuit setups between VCRs and
monitors to make the multistandard switching easier to implement. As rar as I
know, Brazil is the only country that uses PAL with anything other than
625/50/443. Channel spacing, sound/vision spacing and vestigial sidebands may
vary, but timings and frequencies of the actual video signal don't.
Rod.
PAL in Brazil is 525/60/3.58 "PAL-M", and PAL in Argentina is 625/50/3.58
"PAL-N" or "PAL-NC".
Argentina definitely uses a variant of PAL, and it's different from the one
in Brazil. AFAIK all System N countries were supposed to use the 3.58 MHz
variant of 625 line PAL, since this is how System N works. It's the 625 line
system used in the smaller American TV channel which is only 6 MHz wide. In
the days of Black & White television it wasn't much of a drawback beacuse
the only difference it made was a reduction of the vision bandwidth from 5.0
MHz (System B) to 4.2 MHz (System N). But when colour came along they had to
change the subcarrier to a lower non-standard frequency. Argentina uses
this, but the mystery is that the other System N countries don't. They are
listed as using 625/50/4.43 (see links in my previous post) inspite of the
fact that this does not fit into a System N TV channel.