PAL: Pay Again for Luxury.
(In the UK, anyways. ;o)
"The basics of PAL and the NTSC system are very similar; a quadrature amplitude modulated subcarrier carrying the chrominance information is added to the luminance video signal to form a composite video baseband signal. The frequency of this subcarrier is approximately 4.43 MHz for PAL, compared to approximately 3.58 MHz for NTSC. The SECAM system, on the other hand, uses a frequency modulation scheme on its colour subcarrier.
"The name "Phase Alternating Line" describes the way that the phase of part of the colour information on the video signal is reversed with each line, which automatically corrects phase errors in the transmission of the signal by cancelling them out. Lines where the colour phase is reversed compared to NTSC are often called PAL or phase-alternation lines, which justifies one of the expansions of the acronym, while the other lines are called NTSC lines. Early PAL receivers relied on the imperfections of the human eye to do that cancelling; however this resulted in a comb-like effect on larger phase errors. Thus, most receivers now use a chrominance delay line, which stores the received colour information on each line of display; an average of the colour information from the previous line and the current line is then used to drive the picture tube. The effect is that phase errors result in saturation changes, which are less objectionable than the equivalent hue changes of NTSC. A minor drawback is that the vertical colour resolution is poorer than the NTSC system's, but since the human eye also has a colour resolution that is much lower than its brightness resolution, this effect is not visible. In any case, NTSC, PAL and SECAM all have chrominance bandwidth (horizontal colour detail) reduced greatly compared to the luminance signal."
(Source:
http://en.wikipedia.org/wiki/PAL , so please take it with a grain of salt.)
Then again, everybody needs a good PAL. ;o)
The black & white baseband for a PAL signal, as commonly used in most of the world anyways (PAL is *not* a video specification in itself like NTSC but rather a standard for colour transmisison) consists of 625 lines at a redraw rate of 50 cycles. As far as I know the baseband for a SECAM signal usually uses the same parametres as well. So if you were to plug in a 625/50 PAL set in a country that only transmits SECAM you would be able to watch the programming in black & white, but no colour.
Apparently this same phenomenon can be observed in Brasil with an NTSC receiver, because they use a 525/60 PAL "hybrid" (if I can call it that without looking like a complete pillock) called PAL-M.
--http://en.wikipedia.org/wiki/PAL-M_%28television%29 , again, take it for what it is worth.
;D (Of course, once the entire world's using DVB this'll only be a moot issue.) ;D