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The magnetic head design would not permit bandwidths over 1 meghertz to be recorded regardless of the tape speed. The first efforts at video recording, using recorders similar to audio recorders with fixed heads, were unsuccessful. The first such demonstration of this technique was done by BCE on 11 November The result was a very poor picture. Another of the early efforts was the Vision Electronic Recording Apparatus , a high-speed multi-track machine developed by the BBC in Despite 10 years of research and improvements, it was never widely used due to the immense length of tape required for each minute of recorded video.
By BCE also had moved on to multi-track machine, but found limitations in recording bandwidth even at the high speeds. In BCE discovered that the magnetic head design was the problem. This problem was corrected and bandwidths exceeding the 1 megahertz limit were able to be recorded. In BCE demonstrated a broadcast quality color recorder that operated at inches per second and CBS ordered three of them.
Many other fixed-head recording systems were tried but all required an impractically high tape speed. It became clear that practical video recording technology depended on finding some way of recording the wide-bandwidth video signal without the high tape speed required by linear-scan machines. Norikazu Sawazaki developed a prototype helical scan video tape recorder. By recording on the full width of the tape rather than just a narrow track down the center, this technique achieved a much higher density of data per linear centimeter of tape, allowing a lower tape speed of 15 inches per second to be used.
The Ampex VRX became the world's first commercially successful videotape recorder in It uses the 2" quadruplex format, using two-inch 5. Ampex's quadruplex magnetic tape video recording system has certain limitations, such as the lack of clean pause, or still-frame, capability, because when tape motion is stopped, only a single segment of the picture recording is present at the playback heads only 16 lines of the picture in each segment , so it can only reproduce recognizable pictures when the tape is playing at normal speed.
The helical scan system overcame this limitation. In Toshiba released the first commercial helical-scan video tape recorder. The Telcan, produced by the Nottingham Electronic Valve Company and demonstrated on June 24, ,  was the first home video recorder. However, there were several drawbacks: The Sony model CV , first marketed in , is their first VTR intended for home use and is based on half-inch tape.
Prerecorded videos for home replay became available in The EIAJ format is a standard half-inch format used by various manufacturers. EIAJ-1 is an open-reel format.
EIAJ-2 uses a cartridge that contains a supply reel, but not the take-up reel. Since the take-up reel is part of the recorder, the tape has to be fully rewound before removing the cartridge, which is a relatively slow procedure.
The development of the videocassette followed other replacements of open-reel systems with a cassette or cartridge in consumer items: Before the invention of the video tape recorder, live video was recorded onto motion picture film stock in a process known as telerecording or kinescoping. Although the first quadruplex VTRs record with good quality, the recordings cannot be slowed or freeze-framed , so kinescoping processes continued to be used for about a decade after the development of the first VTRs.
In the technique used in all transverse-scan video tape recorders, the recording heads are mounted in a rapidly spinning drum which is pressed against the moving tape, so the heads move across the tape in a transverse or nearly vertical path, recording the video signal in consecutive parallel tracks sideways across the tape. This allows use of the entire width of the tape, storing much more data per inch of tape, compared to the fixed head used in audio tape recording, which records a single track down the tape.
The heads move across the tape at the high speed necessary to record the high-bandwidth video signal, but the tape moves at a slower speed through the machine.
In addition, three ordinary tracks are recorded along the edge of the tape by stationary recording heads. For correct playback, the motion of the heads has to be precisely synchronized with the motion of the tape through the capstan, so a control track of synchronizing pulses is recorded.
The other two tracks are for the audio channel and a cuing track. The early machines use the Ampex 2 inch quadruplex system in which the drum has 4 heads and rotates at 14, RPM perpendicular to the tape, so the recorded tracks are transverse to the tape axis. The helical scan methods use a recording drum with a diagonal axis of rotation.
This allows an entire frame to be recorded per track. This simplifies the electronics and timing systems. It also allows the recorder to be paused freeze-framed during playback to display a single still frame, by simply stopping the tape transport mechanism, allowing the tape heads to repeatedly pass over the same track. This recording technique has many potential sources of timing errors. If the mechanism runs at an absolutely constant speed, and never varies from moment to moment, or from the time of recording to the time of playback, then the timing of the playback signal is exactly the same as the input.
However, imperfection being inevitable, the timing of the playback always differs to some extent from the original signal. Longitudinal error error arising from effects in the long direction of the tape can be caused by variations in the rotational rate of the capstan drive, stretching of the tape medium, and jamming of tape in the machine. Cable, satellite, and other specialty television providers in the United States.
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Following this, much of the VTR market, in particular videocassettes and VCRs popular at the consumer level, were also replaced by non-tape media, such as DVD and later Blu-ray optical discs. In BCE discovered that the magnetic head design was the problem.