Type A videotape

Type A videotape
Ampex VR-7800 VTR at DC Video
Media type Magnetic Tape
Encoding NTSC, PAL
Write mechanism magnetic single-head[1]
Usage Video production

1 inch type A (designated Type A by SMPTE) is a reel-to-reel helical scan analog recording videotape format developed by Ampex in 1965, that was one of the first standardized reel-to-reel magnetic tape formats in the 1 inch (25 mm) width; most others of that size at that time were proprietary. It was capable of 350 lines.[2]

Type A was developed as mainly an industrial and institutional format, where it saw the most success. It was not widely used for broadcast television, since it did not meet Federal Communications Commission (FCC) specifications for broadcast videotape formats; the only format passing the FCC's muster at the time was the then-industry-standard 2-inch quadruplex.

The Type A format received broad use by the White House Communications Agency from 1966 to 1969. The WHCA, under U.S. President Lyndon B. Johnson, used the format to videotape television broadcasts off the air or from direct White House feeds.[3] The WHCA recorded programs and events including television appearances by President Johnson, special news broadcasts and news interview programs. Beginning on April 1, 1968, the WHCA taping system was expanded to also include daily morning and evening news programs, both network and local. When U.S. President Richard M. Nixon succeeded Johnson in office in 1969, the WHCA's Type A recording system was continued until it was gradually phased out, later that year, in favor of a recording system using a 2 inch format.[4]

Early VTRs were black-and-white (B/W) only, later VTRs supported color television, with a heterodyne playback. Still later units had time base correction playback, like the VPR-1 that could be used at television station and post-production houses.

The VPR-1 had several problems, it did not record the vertical blanking interval, which is why it was not compliant to FCC broadcast standards. The video quality was not as good as other broadcast VTRs. Thus Sony and Ampex agreed to make a SMPTE approved type C format VTR (which was based on Type A). Hitachi also later made a C format VTR.

Helical recording method

Some Ampex Type A Models

See also

References

Notes

External links

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