RSHAPIRO@A.BBN.COM (Richard Shapiro) (03/14/86)
I had always been under the impression that PAL, SECAM and NTSC referrred only to color systems and not, for example, to number of lines. In fact I thought that there were both 525 PAL and 625 PAL around. Is this wrong? Also I seem to remember someone claiming on this list to have watched a 625 PAL videotape on an NTSC VCR + monitor and gotten slightly distorted but watchable (monochrome) results. True? Also, is it correct to assume that HDTV will render all of this obsolete once it's adopted? Is it looking like an international standard wrt number of lines, color, etc.? Is HDTV supposed to be back compatible in some way or am I going to have to junk all of my video equipment (assuming I can live without state-of-the-art)? Just wondering. -------
OLE@SRI-NIC.ARPA (Ole Jorgen Jacobsen) (03/15/86)
Richard, The number of lines is definately part of the standard, all PAL systems are 625, there is (was?) supposedly an 819 line SECAM system (all the common ones are 625), while all NTSC systems are 525. The old British standard (black and white) used 405 lines, this has now been phased out. What does vary within each standard is the *broadcast* format, that is distance between sound and picture carrier, frequency band used, type of modulation (AM/FM). Look in "World Radio TV Handbook" (the DXers best friend!) for more details. Look at MRCs message on the Instant replay machine regarding how to do PAL on a NTSC system in a kludegy way. HDTV, digital TV or whatever wins in the end will most likely not be backwards compatible, but assuming the world can agree we will only have *one* standard and not umpteen. Ole -------
keithe@tekgvs.UUCP (Keith Ericson) (03/18/86)
In Brazil they use a variant of PAL called PAL-M (Modified?) that is a 525-line, 60 Hz system. To the best of my knowledge it's only used there and a couple of other (very) small countries around there. keith