The U-Matic video cassette formate was introduced by Sony and an improved version of the U-matic was introduced in 1986. This improved formate was called the SP, instead of 3.8-5.4MHz recording frequency the SP has a 5.0-6.6MHz. These tapes could record up to 60 minutes of video and was mainly used by industry and education. In the 1970 and 80''s it was mainly used for news. On the videotape themselves there was a detection system the this recorder would use to figure which mode to record with.
This recorder plays the SP video, but was compatible for with the conventional U-matic video. Some features that this recorder had was Dolby noise Reduction/Auto Detection system, the adoption of a Sendust head, and audio dubbing.
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