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Normally we would advise against buying any video or TV related products whilst abroad or on holiday, but you can buy blank tape, and be reasonably sure it will work in your equipment. Thereís a few ifs and buts, however, the main point is the magnetic tape spooled inside cassettes, destined for countries that use the PAL, NTSC and SECAM colour TV systems, is exactly the same. That applies to all domestic tape formats, whether theyíre for high or low-band systems, analogue or digital.


The actual amount of tape inside analogue cassettes does vary however, and thatís because of the differences in the tape transport speed between the PAL and NTSC systems. (DVC camcorders and VCRs operate at the same tape speed, but the way the digital data is configured is different). SECAM VCRs and camcorders operate at the same as PAL machines and cassettes sold in this country are normally labelled as being suitable for PAL and SECAM equipment. NTSC analogue VCRs and camcorders run at a slightly higher speed than PAL machines, so NTSC blank tapes will actually last a little longer than the times printed on the sleeve. In real terms the difference are fairly small, thereís around 3% more tape in a NTSC cassette of any given length.  


Whilst itís okay to buy blank video tape when youíre on holiday, itís quite another matter with pre-recorded material. Generally speaking thereís no compatibility problems with PAL and SECAM recordings;  the differences are mainly to do with the way the colour information is processed before and after itsí recorded or replayed; the actual signals that end up on the tape is the same in both cases. Thatís not to say PAL and SECAM equipment is interchangeable though. If you try to play back a SECAM recording on a PAL machine (and vice-versa), you will get a stable picture, but it will be in black and white.


The situation is more clear cut with PAL and NTSC recordings and equipment, and itís fair to say that if youíve got friends of relatives living in the US, or the parts of the far East where they use the NTSC system, they will have the devilís own time watching any PAL recordings you send to them. Unless they happen to have multi-standard equipment, they will almost certainly have to have the recording transcoded -- copied to their system -- before they can watch it. On the other hand, if youíve got a reasonably recent TV, and a VCR with an NTSC replay feature, thereís a very good chance you will be able to play and watch their tapes on your equipment. Unfortunately this only extends as far as VCRs, only a couple of camcorders have NTSC replay. This feature is a useful spin-off from the steady internationalisation of TV and video equipment. To save costs and help rationalise production, TV manufacturers often use the same type of video processing microchips in TVs destined for PAL and NTSC countries. These TVs can be persuaded to display partially decoded colour signals, though it only works in one direction, and thereís no equivalent feature on NTSC VCRs and TVs.



* A typical VHS video cassette contains 32 components; that includes the outer sleeve and sticky labels...


* Thereís 258 metres of tape inside a 3-hour VHS cassette. You would need the tape from approximately 5000 E-180s to stretch around the equator, and around 150,000 to reach from the Earth to the moon.  


* On average it takes about half an hour to assemble a VHS cassette. Most of the processes in tape manufacture are now relatively Ďcleaní and do not involve the release of harmful chemicals. In fact video cassettes must be one of the most environmentally-friendly products there are. Most video cassettes are either recycled by constant re-recording, or archived. Very few are thrown away, and if properly disposed of, the plastics can be easily recovered.


* Why are video cassettes always black? They donít have to be, though they have to be light-proof, as VCRs and camcorders use optical sensors, to detect when the cassette is in place, and the beginning and the end of the tape. Several companies have tried marketing coloured cassettes from time to time, but usually with limited success. Research has shown the public perceive coloured cassettes to be Ďcheapí or low quality items; thatís probably a hangover from the days of coloured LPs, which often sounded really horrible. Black is the most popular colour with manufacturers because the carbon-based pigment is very stable, inexpensive and resistant to a build up of static charges.


* Video tapes can kill! Fire brigades around the country are becoming increasingly concerned about the hazard posed to householders and fire-fighters by collections of tapes, in house fires. A typical VCR owner will have between 50 and 100 tapes, usually all together in one fairly confined space. This represents a significant quantity of flammable plastic, that will burn and give off large volumes of highly toxic gasses, when exposed to fire.


* Normal VHS tape is between 18 and 20 micrometers thick, (a micrometers is a millionth of a metre); of that the magnetic layer is only 3.5 to 4.5um thick. The base film, on which the magnetic layer is coated, is made out of polyester or PET (polyethylene terephlalate), the plastic they make lemonade bottles out of).


* The magnetic layer on video tape contains an incredible mixture of exotic chemicals, most of which have no magnetic properties at all. It includes pigments, dispersants, light inhibitors, electro-conductive substances, abrasives, lubricants, solvents, binders, and good old cross-linking polymers.


* DVC tapes are the thinnest, theyíre just 7um thick. Hi8 metal evaporated (ME) tapes are 11um thick and 8mm and Hi8 metal particle (MP) tape is 13um thick.


* BASF, TDK, 3M, JVC, THATs; manufacturers whose names are acronyms abound in the magnetic tape industry, but what do they all mean? BASF stands for Badische Anilin und Soda Fabrik; TDK is Tokyo Denki Kagaku, the three ĎMsí in 3M are Minnesota Mining and Manufacturing, and JVC are better known to their friends as the Victor Company of Japan. THATs, as far as we can make out, doesnít stand for anything.



R. Maybury 1996 1208



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