Quadruplex VR2000 recording machine

This is the very first device for recording the TV image on a magnetic tape, the same technology that later appeared in households as the VHS video system. At the dawn of television, the only solution for recording the TV broadcast was to set a movie camera in front of a TV receiver and record the image on a film. This system was called the "telerecording". The developed film could be broadcast again using a film scanner. Usually, everything was broadcast live. In the USA, the television companies had a serious problem - the country was divided into several time zones and if a certain piece of programme was to be broadcast at the same time in each of the time zones, the live broadcast had to be recorded on film which was then developed and re-broadcast a hour later. This was a very expensive process, the TV companies consumed more raw film stock each year than the entire Hollywood business. The market demanded a magnetic tape recorder. The tape can be played immediately after recording and can be erased and used again.

Recording a TV image on a magnetic tape is a great challenge because of the required band width. The usual linear recording, as in audio tape recorder, cannot be used, because the tape would have to run at several meters per second. The Ampex company solved the problem by placing the magnetic heads on a drum rotating at 15 000 RPM and the signal was recorded in narrow tracks perpendicular to the length of the tape, which runs at reasonable speed of 39,6875 cm/s. The system used four heads which switched one after another and so was called the Quadruplex. The tape width is 2 inch, so more than 5 cm. One reel could hold about one hour of recording. The machine was extremely delicate, the head drum was supported by air bearings filled with a compressor, the tape was sucked against the heads by a vacuum pump. Another great challenge was modifying the machine for color signal, which is very sensitive to even the slightest phase errors introduced by tiny variations in tape and drum speed. The Ampex company was the only manufacturer of this system for many years. Series production started in 1956. The Soviet Union tried to make a copy of the system, but was not successful.

The Czechoslovak Television also needed the magnetic recording system since the sixties. The only solution was to import the machine from the USA. But the export of Quadruplex to the Eastern Bloc was banned, because the system could be used in military applications. The Czechoslovak TV decided to smuggle the machine in. Officially, the machine was sold to Italy, from where it was transported to Czechoslovakia. The machines were used until the beginning of the nineties. One reel of tape was said to cost as much as a new Škoda automobile. One machine has been kept in running condition until today, so in case that a forgotten tape is found, it can be played. The last time this happened was in 2016 when a recording of the "Golden Nightingale 1967" (Zlatý slavík, a TV contest for the best Czechoslovak pop singer) was found. In this season, some singers, who later happened to be politically unacceptable, appeared in the contest and no recording was known to be preserved before the finding. The tape was scanned and broadcast exactly 50 years after its recording.