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Some American manufacturers made a few "Simple PAL" receivers for the South American market, I believe.
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They discontinued it, when Matsushita bought their TV business. |
#3
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I posted this elsewhere but here is a interesting set on the oldtechnology site
http://www.oldtechnology.net/images/ekcoct100m.jpg the details are found on this page http://www.oldtechnology.net/colour4.html
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#4
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When Australia introduced colour in the 1970s (very late to the party).. we adopted PAL... with Telefunken owning the patents only Oz and European manufacturers were licenced to sell sets here...well that was the plan until GE announced they were happy to licence the Japanese companies.... thru their cross patents with Telefunken. The result that Sony etc were able to sell full PAL-D sets.
A number of other sets were directly imported by retailers. Hence the Sony 13" mentioned above... the only Sony set officially released here was the KV1800AS ... a full PAL-D set but multistandard sets were available as well with European PAL G tuners (which did not receive our odd channel 5A)
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____________________________ ........RGBRGBRGB ...colour my world |
#5
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So the sneaky Sony TV would store the 'NTSC' lines and repeat them in place if the sequential 'PAL' lines
A standard PAL-D TV would store the 'NTSC' line and process it with subsequent 'PAL' line. This would halve the chroma vertical resolution. But it gets worse because of interlaced scanning: now sampled detail from two lines above is added to 'PAL' line creating more degradation than unprocessed pure 'PAL' & 'NTSC' lines (as in a PAL-S receiver)? And if there is picture motion even more blur. Last edited by NewVista; 07-30-2014 at 02:34 AM. |
Audiokarma |
#6
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#7
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All colour TV systems have reduced horizontal resolution for the chroma signals. Legacy analogue PAL/NTSC/SECAM, SD-SDI, HD-SDI and 4K. Some digital transmission methods, sometimes known as 4:2:0 as against the usual 4:2:2, reduce vertical resolution likewise. All of this takes advantage of the fact that the eye cannot resolve fine detail in colour the way it can in monochrome.
If the H colour resolution is already halved (even more reduction in analogue) then halving vertical resolution really doesn't matter. Incidentally, a standard PAL-D decoder moves the chroma half a line down the screen compared to the luma. Again this doesn't show. It matters if you're recovering old PAL material where you would normally be using much better decoders that don't have this effect. |
#8
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First PAL sets used visual averaging of complementary hue errors (if any) over odd & even line pairs with different line in between creating annoying "venetian blind" artifact. Disastrous idea given interlaced scanning.
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#9
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#10
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AFAIK all UK colour TVs used delays lines and so didn't show Hanover blinds (or bars) unless the decoder was misaligned. The early Sony sets effectively converted PAL to NTSC and so didn't show them either.
The Telefunken PAL patents were administered by EMI in the UK. All the receiver manufacturers paid but EMI didn't both to chase the broadcast equipment manufacturers who made PAL encoders. I think this was a sort of de minimis thing as the numbers of encoders was tiny compared to decoders. Until some time in the early 1980s when EMI were going through one of their many financial panics. I was working at Michael Cox Electronics at the time and EMI threatened the company with royalty payments for all the 1000+ coders that MCE had manufactured since the late 1960s. I don't know how that was resolved. |
Audiokarma |
#11
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If PAL-Delay were working with progressive scan then V chroma res would be halved, but with interlace it becomes way more disastrous: The summed interlace pairs have double the separation. This, and its diminished "Kell factor" would take V chroma res down to <80 'lines'. Same for H chroma res with motion - maybe down to ~50 lines.
NTSC-M could achieve ~ 100 x 350 'lines' chroma |
#12
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Since chroma bandwidth is much lower than luma the reduction in vertical resolution doesn't matter. PAL decoding just about equalises the H and V chroma resolutions.
PAL decoding also moves the chroma down by half a line wrt luma. Again this doesn't matter unless you cascade codecs. More modern comb filter decoders can keep the Y and C in vertical alignment. |
#13
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"..moves the chroma down by half a line wrt luma."
The way I see it, it would be two lines displacement (line 1 to 3, line 2 to 4...)? This would be another PAL-D chroma artifact - creating headaches for designers of decoders for standards converters.. The H res one being worse than progressive scan conversion sans motion compensation which blurs so badly designers would rather just double fields (in early days) kind of like THAT notorious Sony "PAL" TV did). Only the Germans could come up with such a Heath Robinson solution to Hanover Bars. Last edited by NewVista; 08-02-2014 at 10:17 AM. |
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PAL and SECAM were variations on a theme developed by NTSC. The acronyms I have heard for each are interesting and define well the politics between the variations:
NTSC - Never Twice the Same Colour (as explained earlier in this threa) PAL - Problems Are Lurking - This name probably arose from the editing of PAL. It was painful because of the 8 field colour sequence rather than the four NTSC offered. SECAM - System Essentially Contrary to the American Method - With France and it possessions and the Soviet Bloc adoption, the name says it all. |
#15
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Canada could have easily fallen prey to the German propagandists and ended up paying license fees for PAL-M like those suckers in Brazil.
Fortunately Canadian bureaucrats were on the ball. |
Audiokarma |
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