Betamax the Loser of the Home Video Format War. Betamax is a consumer-level analog-recording and cassette format of magnetic tape for video. It was developed by Sony and was released in Japan on May 10, 1975. The first Betamax device introduced in the United States was the LV-1901 console, which included a 19-inch (48 cm) color monitor, and appeared in stores in early November 1975. The cassettes contain 0.50-inch-wide (12.7 mm) videotape in a design similar to that of the earlier, professional