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Chapter1   The Video Cassette Tape

The Video Cassette Tape

In 1964, a team led by Nobutoshi Kihara developed the CV-2000, the world's first VCR intended for home use. This was the first step toward realizing Masaru Ibuka's dream of creating a video player that would be suitable for home use in terms of both size and price.

The CV-2000 was roughly the same size as an audio tape recorder of that time. This VCR, which had two rotary heads, was a reel-to-reel type unit and it reproduced fantastic black and white images. In addition, the price of the CV-2000 was less than one-hundredth a broadcast-use model, and less than one-tenth the price of an institutional model. The machine's key feature was the use of rotary heads, which cost more than static heads. This disproved the commonly held view of many in the industry that rotary heads employed for broadcast and institutional-use models could not be adapted for a home-use VCR. The world gasped in wonder at the picture quality of the new machine, and Kihara could proudly answer previous skeptics by saying, "Technology does not abide by common sense. Our goal is to break down ideas people have come to accept as common sense."

Although manufactured as the first home-use VCR, most of the CV-2000 machines were actually used for medical and industrial purposes before finding their way into schools and, eventually, homes. So in spite of the "home-use" label, in reality the reel-to-reel type CV-2000, which could record and play back black and white images, proved to be an extremely popular institutional model.

But before long, the Sales Department expressed dissatisfaction with reel-to-reel type black and white VCRs. Sales people requested color models and asked engineers if they could design a VCR that used a cassette tape similar to an audio tape recorder.

As the name "reel-to-reel" suggests, the reels that hold and wind the tape are separate units located on top of the actual VCR deck. The user has to pull the tape from the supply reel and feed it through the record and playback devices to wind the reel each time to operate the machine. Besides being extremely inconvenient, the process is tricky as the tape can easily be damaged when handled. The use of a cassette tape would eliminate this problem by allowing the user to operate the machine by simply placing the cassette tape in the deck, which would then, automatically run the tape. The move from reel-to-reel to cassette was rapidly occurring in the audiotape industry at this time.

  • The "Lunch Box Cassette," one of Kihara's experimental products.
Kihara grumbled, "The construction of a VCR is very complex. It will be extremely difficult to build a machine that will use a cassette tape, let alone in color. You don't understand what you are asking the engineers to do!" Nevertheless, Ibuka persisted with Kihara; "Look how easy audio tape recorders can be used thanks to the cassette tape! Why can't we incorporate this function into video players? This is the obvious next step that has to be taken in the development of this product." Deep down, Kihara knew that Ibuka was right.

The task then was to incorporate into the VCR deck the hold and play functions into the VCR deck. These functions had previously been performed by the devices on top of the deck. This was to be achieved with a cassette tape that could be used in a similar fashion to those used by audio tape recorders. However, in the case of a VCR, a further mechanism had to be included to automatically pull the tape from the cassette case so that the tape could pass over the drums attached to the record and playback heads. In other words, not only did the VCR have to play a tape housed in a cassette; it had to have an automatic loading function too.

Thus, Kihara and his team recognized three major challenges: to incorporate color, to develop a video cassette tape, and to design an automatic loading function. They developed countless prototypes, but most were unusable. Despite the obstacles, and after many failed attempts, Kihara eventually delivered the first usable prototype in 1968.

Freedom of Thought and Creation-the Kihara Method

Popularly known as the "Kihara's School," the 2nd Development Division operated with the goal of nurturing talented personnel while creating new technologies. Kihara created an environment where young engineers could think freely and apply the latest technologies to create new products.

Kihara was involved with all of Sony's magnetic recording technology developments--the wire corder, audio tape recorder and VTR. All of these products became the leading electronics products of their time. Kihara emphasized to his protégeš the importance of setting a clear target and then focusing one's energies on achieving that target.

Engineers Akinao Horiuchi and Yoshimi Watanabe were given the difficult task of developing the new cassette tape system. Their first step was to reduce the amount of tape required to display video images. In other words, their goal was to compress as much information on to the shortest length of tape possible. Horiuchi and Watanabe began by looking for a tape with a higher recording density than the gamma-iron tape that was widely used for recording video at the time. The answer was provided by the Sendai factory in the form of chrome-oxidized tape, which the development team was able to adapt for video use. The supply and take-up reels that had traditionally been placed in a side-by-side arrangement were instead placed in a slightly overlapping configuration, saving space and enabling a cassette tape of more compact design.

  • The U-loading system-a simplified loading system.
The next hurdle was to develop an automatic loading system. "Nothing too complex," urged Kihara, "try to find a simple and reasonable design. Remember that it must be easy for people to use." With this request in mind, Horiuchi and Watanabe began to build a sturdy, uncomplicated loading mechanism that was easy on the tape and would automatically pull it from the cassette case and feed it over the rotary drum heads without damaging nor putting excess tension on the tape. Many ideas were proposed for the new loading mechanism, including those with unique names such as the "Cast Net" system and the "Ranch" system. After exhaustive research, the development team was confident it had devised a mechanism that could be used for cassette tape VCRs, the "U-loading" system. The name was derived from the U-shaped figure the tape followed when seen from above. Since its design minimized the amount of tension applied to the tape during record and playback, this loading system was able to truly cut tape vibration that caused jittering. Moreover, the new design ensured that the tape would play at a constant speed.

The only remaining hurdle was to provide color. A color system called the "Y/C Signal Separation System," which recorded luminance and color signals on different tracks, already existed. But the development team decided to devise a new system based on an idea conceived by Toshihiko Numakura. Called the "Color-Under System," this recorded color and luminance signals on the same track by employing a frequency modulator. Also known as the "Numakura Patent," it became the system on which subsequent VTR color-recording systems were based.

Enthused by the passion of Kihara and supported by the contributions made by the Sendai factory, the 2nd Development Division solved their three major tasks and achieved the goal of placing the awkward seven-inch size reel tape into a cassette tape.

Not Quite Suitable for the Home-the U-matic VTR


  • Ibuka announces the release of the Sony Color Videoplayer, a prototype of the U-matic VTR.
Popularly known as the "Kihara's School," the 2nd Development Division operated with the goal of nurturing talented personnel while creating new technologies. Kihara created an environment where young engineers could think freely and apply the latest technologies to create new products.

Kihara was involved with all of Sony's magnetic recording technology developments--the wire corder, audio tape recorder and VTR. All of these products became the leading electronics products of their time. Kihara emphasized to his protégeé the importance of setting a clear target and then focusing one's energies on achieving that target.

Engineers Akinao Horiuchi and Yoshimi Watanabe were given the difficult task of developing the new cassette tape system. Their first step was to reduce the amount of tape required to display video images. In other words, their goal was to compress as much information on to the shortest length of tape possible. Horiuchi and Watanabe began by looking for a tape with a higher recording density than the gamma-iron tape that was widely used for recording video at the time. The answer was provided by the Sendai factory in the form of chrome-oxidized tape, which the development team was able to adapt for video use. The supply and take-up reels that had traditionally been placed in a side-by-side arrangement were instead placed in a slightly overlapping configuration, saving space and enabling a cassette tape of more compact design.

The next hurdle was to develop an automatic loading system. "Nothing too complex," urged Kihara, "try to find a simple and reasonable design. Remember that it must be easy for people to use." With this request in mind, Horiuchi and Watanabe began to build a sturdy, uncomplicated loading mechanism that was easy on the tape and would automatically pull it from the cassette case and feed it over the rotary drum heads without damaging nor putting excess tension on the tape. Many ideas were proposed for the new loading mechanism, including those with unique names such as the "Cast Net" system and the "Ranch" system. After exhaustive research, the development team was confident it had devised a mechanism that could be used for cassette tape VCRs, the "U-loading" system. The name was derived from the U-shaped figure the tape followed when seen from above. Since its design minimized the amount of tension applied to the tape during record and playback, this loading system was able to truly cut tape vibration that caused jittering. Moreover, the new design ensured that the tape would play at a constant speed.
The only remaining hurdle was to provide color. A color system called the "Y/C Signal Separation System," which recorded luminance and color signals on different tracks, already existed. But the development team decided to devise a new system based on an idea conceived by Toshihiko Numakura. Called the "Color-Under System," this recorded color and luminance signals on the same track by employing a frequency modulator. Also known as the "Numakura Patent," it became the system on which subsequent VTR color-recording systems were based.

Enthused by the passion of Kihara and supported by the contributions made by the Sendai factory, the 2nd Development Division solved their three major tasks and achieved the goal of placing the awkward seven-inch size reel tape into a cassette tape.

Paperback Book Sized Cassettes

"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.

  • A target is set to reduce the size of the video cassette tapes to the size of a paperback book.
    (Shown here is Sony's first Betamax VCR, the SL-6300).
Sony began work on developing prototype home-use VCRs based on these two new technologies. Creating the new machines was like building a castle from stone blocks. Employees in charge of different aspects of the project would carve their own building blocks and drag them before the design team, which would then carefully place each block in position until the ideal castle was completed. The prototypes were grand conglomerations of materials, parts, and circuits, each one being as indispensable to the operation of the machine as any other. Important contributions to the prototypes came from many areas of the company. The Sendai factory supplied an important component such as a high-density recording tape. The Semiconductor Group in Atsugi made a major contribution by coming up with a design for a new integrated circuit (IC).

In 1973, after the development of the prototypes was completed, Kohno's group was separated from the 2nd Development Division and became the Betamax R&D Group (Gijutsu Junbi-shitsu). This group concentrated on preparing production facilities for the new VCRs. Kihara's School was effectively disbanded, and the personnel in charge of individual projects were relocated to establish independent production and business divisions. In this way, the product development process was carried through to the very end, with the original product ideas, concepts and the knowledge accumulated in the development process being effectively utilized in both production and marketing.

"This is a Revolution!"

The result of the fervent development push was a VCR that used a Sony Diary sized video cassette tape, two-thirds the weight of the U-matic. The number of parts used was about half the number of the U-matic cassette tape. The new tape had a width of half an inch. Morita, president of Sony at the time, thought to himself, "This is a revolution!" Around 1973, the percentage of color televisions in Japanese households was overtaking that of black and white televisions. The VCR was the answer to the question on many people's lips: "What comes after the color TV?" Key players in the consumer electronics industry set out with vigor to deliver the answer to consumers, and Sony was very quick to have an answer. Sony's new VCR could be connected to a television and used to record one hour of video and audio. The TV guide no longer restricted what people watched on their televisions. They could record whatever programs they liked and replay them when they wanted. It truly was an entertainment revolution that would completely change people's lifestyles.

  • The press conference announcing the Betamax VCR.
    Ibuka is holding a Betamax tape in his right hand (To compare the size, Ibuka is holding a 2-inch broadcast tape in his left hand).
Sony had to think of an appropriate name for this definitive product. What Kihara called the "Azimuth Recording" had been nicknamed the "Beta Recording," "beta" being the Japanese word used to describe the way signals were recorded onto the tape. From this sprung the idea of using the word "beta." Just as the tape path in the U-matic loading system resembled the letter "U," the tape path in the new loading system closely resembled the Greek letter or beta, when seen from above. This symbol is associated with good luck and can be construed as a drawn out pronunciation of the English word "better." "Max," an abbreviation of the word "maximum" was intended to impart a meaning of grandness, and was then added to the end. The name "Betamax" was born.

While Sony believed it had a revolutionary product on its hands, it still had to convince consumers throughout the world how to benefit from a Betamax VCR in their homes. Morita thought the best way to achieve this was through a short, catchy slogan, and the slogan "time-shift" was created. This encapsulated the core concept behind the Betamax; to build a machine that frees consumers from the constraints of watching television programs on the day they are broadcast. With the time-shift function, consumers could record their favorite programs and watch them whenever they liked.

By 1975, color televisions could be found in over 90% of Japanese households and they had become an integral part of people's daily lives. Just as the relationship between the radio and the audio tape recorder had fueled sales of both products, it was thought that the relationship between the color television and the home-use color VCR would trigger sales of both products. Sony was convinced that the time was right.

On April 16, 1975, Sony announced its latest VCR products, the SL-6300 VCR deck and the LV-1801, a TV/VCR combination unit that incorporated the SL-6300 and an 18-inch Trinitron color television. Both products were released for sale nationwide on May 10. The SL-6300 sold for 229,800 yen, approximately the same price as a large color television and only around 60% of the price of a U-matic machine. The accompanying video cassette with a playing time of 60 minutes was priced at 4,500 yen or less than half the price of a U-matic video cassette. The LV-1801 was 449,800 yen, approximately twice the price of a large color television.


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