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Helical scan
Method of recording high-frequency signals on magnetic tape / From Wikipedia, the free encyclopedia
Helical scan is a method of recording high-frequency signals on magnetic tape, used in open-reel video tape recorders, video cassette recorders, digital audio tape recorders, and some computer tape drives.
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![]() Helical recording method | |
Media type | magnetic tape |
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Usage | recording high-frequency signals |
With this technique, magnetic tape heads (or head chips) are placed on a rotating head drum,[1] which run the chips at high speed (or angular velocity). The tape is wrapped tightly around the drum. The drum[2] and/or the tape is tilted at an angle that allows the head chips to read the tape diagonally, and the linear speed of the tape is slower than the speed of the head chips, allowing signals to be transmitted. High frequency signals, such as video, are recorded.[3][4][5] The diagonal tracks read or written using this method are known as helical tracks.[2]
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