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CHAPTER FIVE ....VIDEOTAPE Shortly after the end of the second world war, the B.B.C. experimented with a machine to record a television picture on magnetic tape. With the state of the art at the time this took the form of a monster that spun six foot diameter reels of recording tape at high speed to record thirty minutes of rather scruffy black and white image. No one ever went near this thing when it was running. In 1956, Ampex introduced video tape recording to broadcast television with a machine in which a two inch tape moved at a reasonable speed, while a rotating assembly of four video heads scanned the tape as it passed. This "Quad" machine was about the size and weight of two refrigerators, and cost a couple of hundred thousand dollars.
All this is just so you will appreciate how far we have come, and so that you will treat that little handful of precision workmanship with care so that it will continue to produce those sharp color pictures. The heart of your VCR is a swiftly spinning video head drum, which scans diagonal tracks across the tape while recording, and has to locate itself in exactly the same place on playback, and here we are talking millionths of a second, otherwise, in your video of your wealthy great-aunt, she will have a green face instead of a purple one, and she will immediately cut you out of her will. In my opinion, about the worst thing you can do to your VCR, outside of dropping it in the swimming pool or backing over it with your car, is to use poor quality tapes. In my shop I will not use any tape that is not recognized by its manufacturer. If he doesn't have enough nerve to put his name on it, I don't have enough nerve to use it. A big splash by the importer does you no good if the tape is made in a back shed in Hong Kong, and the "lifetime guarantee" if it screws up your machine, is limited to giving you another cheap tape. In about twenty years of working with VCRs, I have had no problems with any of these brand names; Scotch-3M, J.V.C. Sony, Panasonic, T.D.K. Polaroid, Kodak, Memorex, BASF and Fuji. The standard quality brand name tape (in the five dollar price range) seems to be OK for everything except recording your daughter's wedding, when you would spring for the best quality tape you could find to avoid the chance of drop-outs. All the above refers to T-120 VHS cassettes, for the back alley manufacturers have not been as anxious to go after the much more limited market of the other, and more expensive, formats. |
