PlayTape
PlayTape was an audiotape format and playback system introduced in 1966 by Frank Stanton. It was a two-track system, and was launched to compete with existing 4-track cartridge technology. A PlayTape cartridge used small ⅛" tape. The cartridges played anywhere from eight to 24 minutes, and were self rewinding. Because of its portability, PlayTape was an almost instant success, and over 3,000 artists had published in this format by 1968. White cases usually meant about eight songs were on the tape.
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