"So you've managed to build this marvelous machine. Just think, the next one will be even better!" Ibuka said this when he was shown the first prototype U-matic machine. This response was typical of his attitude. Even while earnestly congratulating someone for successfully completing a project, he would look ahead to the next step. Ibuka was tireless in the pursuit of his dreams and constantly set demanding targets for his engineers. "It can't be done," were words that he would not easily accept. "I love seeing Ibuka-san with a smile on his face, so I always do my best," said Kihara, referring to the obvious delight that Ibuka greeted any new product or technology.
Soon after the prototype U-matic was completed in 1969, Ibuka directed Kihara to commence work on the development of a next-generation video tape recorder. The goal to create a machine that could truly be described as a home-use VCR never changed. Ibuka had indicated to Kihara that a cassette tape the size of the Sony Business Diary, identical to a Japanese paperback book size, was required. In any case, Kihara knew that the smaller the better.
The know-how accumulated in the development of the U-matic was put to use in designing a new video tape recorder. Fumio Kohno headed a team in charge of the electronics aspects for the new machine, and Akio Serizawa looked after the team responsible for its mechanical aspects.
Having a clearly defined target was the most important thing for Sony's engineers. In the United States, President John F. Kennedy had rallied scientists and industries throughout the country when he declared that the U.S. was going to put a man on the moon. Ibuka motivated every Sony employee by setting a clear and simple target: to develop a Sony Diary sized video cassette tape. With all employees pulling together, Sony rapidly moved toward realizing this goal.
The simple U-loading mechanism developed by Kihara and Horiuchi was further enhanced to enable fast forward and rewind functions while the tape was loaded. Rapid advances were also made in increasing tape recording density. The two new systems that played a leading role in realizing these gains were the Azimuth Recording System and the New Color System (PI System).
The Azimuth Recording System was an idea that had been brewing in Kihara's mind since the development of the U-matic. Between tracks on the tape there is a buffer zone, known as a guard band, where nothing is recorded. Kihara realized that eliminating the guard band would yield a higher recording capacity. However, the guard band had the important function of ensuring the clarity of the picture by preventing crosstalk, i.e., when the VCR heads pick up signals from adjacent tracks. The Azimuth Recording System overcame this problem by positioning the angle of the playback head in such a way as to prevent it from being able to pick up signals from adjacent tracks. The only problem remaining was the crosstalk caused by color signals recorded at low frequencies. This problem was solved by the PI System, a phase-change color signal system. Thus, by effectively removing the guard band and exactly matching the tracks, the recording density of tape was increased three-fold. Kihara and his team accelerated the pace of their work amid rumors that other companies were preparing to release smaller VCRs.