A History of Videotape, Part 1

As a Digital Production Specialist at Duke Libraries, I work with a variety of obsolete videotape formats, digitizing them for long-term preservation and access. Videotape is a form of magnetic tape, consisting of a magnetized coating on one side of a strip of plastic film. The film is there to support the magnetized coating, which usually consists of iron oxide. Magnetic tape was first invented in 1928, for recording sound, but it would be several decades before it could be used for moving images, due to the increased bandwidth that is required to capture the visual content.

Television was live in the beginning, because there was no way to pre-record the broadcast other than with traditional film, which was expensive and time-consuming. In 1951, Bing Crosby Enterprises (BCE), owned by actor and singer Bing Crosby, demonstrated the first videotape recording. Crosby had previously incorporated audiotape recording into the production of his radio broadcasts, so that he would have more time for other commitments, like golf! Instead of having to do a live radio broadcast once a week for a month, he could record four broadcasts in one week, then have the next three weeks off. The 1951 demonstration ran quarter-inch audiotape at 360 inches per second, using a modified Ampex 200 tape recorder, but the images were reportedly blurry and not broadcast quality.

More companies experimented with the emerging technology in the early 1950’s, until Ampex introduced 2” black and white quadruplex videotape at the National Association of Broadcasters convention in 1956. This was the first videotape that was broadcast quality. Soon, television networks were broadcasting pre-recorded shows on quadruplex, and were able to present them at different times in all four U.S. time zones. Some of the earliest videotape broadcasts were CBS’s “The Edsel Show,” CBS’s “Douglas Edwards with the News,” and NBC’s “Truth or Consequences.” In 1958, Ampex debuted a color quadruplex videotape recorder. NBC’s “An Evening with Fred Astaire” was the first major TV show to be videotaped in color, also in 1958.

One of the downsides to quadruplex, is that the videotapes could only be played back using the same tape heads which originally recorded the content. Those tape-heads wore out very quickly, which mean’t that many tapes could not be reliably played back using the new tape-heads that replaced the exhausted ones. Quadruplex videotapes were also expensive, about $300 per hour of tape. So, many TV stations maximized the expense, by continually erasing tapes, and then recording the next broadcast on the same tape. Unfortunately, due to this, many classic TV shows are lost forever, like the vast majority of the first ten years (1962-1972) of “The Tonight Show with Johnny Carson,” and Super Bowl II (1968).

Quadruplex was the industry standard until the introduction of 1” Type C, in 1976. Type C video recorders required less maintenance, were more compact and enabled new functions, like still frame, shuttle and slow motion, and 1” Type C did not require time base correction, like 2” Quadruplex did. Type C is a composite videotape format, with quality that matches later component formats like Betacam. Composite video merges the color channels so that it’s consistent with a broadcast signal. Type C remained popular for several decades, until the use of videocassettes gained in popularity. We will explore that in a future blog post.