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Indian Head test card

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The Indian Head Test Pattern
The Indian Head Test Pattern

The Indian Head Test Card was a black and white television test pattern that was introduced in 1939 by RCA of Harrison, New Jersey as a part of the RCA TK-1 Monoscope. Twentieth century television became so important socially that this mere technical image, covertly identified as a branded industrial product, has become a historic cultural icon.

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As TV viewing ritual

The Indian Head Test Pattern became familiar to large TV audiences that had bought television sets from 1947 on. The Indian Head would often follow the formal television station sign-off after the United States national anthem. This Indian Head pattern was also used in Canada, following the Canadian national anthem sign-off in the evening.

The test pattern could be seen after sign-off while the station was still transmitting, seen while transmitting prior to a typical 6 AM formal sign-on, or seen for many morning hours on newer low budget stations that typically began midday local programs around 10 or 11 AM.

During the late 1950s this test pattern began to be seen for gradually less weekly time, after fewer sign-offs, on fewer stations, and for shorter periods in the morning because newer TV equipment required less adjusting. In later years the test pattern was transmitted for as little as a minute after studio sign-off, while the transmitter engineer logged readings and then turned off the power.

Toward the end of the Indian Head TV era, there was no nightly test pattern on some stations, typically when automatic logging and remote transmitter controls allowed shutdown of power immediately after the formal sign-off. After an immediate transmitter power off, a USA or Canadian viewer heard a loud audio hiss like FM radio interstation noise, and saw an impression of fast-flickering black bugs on a cool white background. UK viewers saw "snow" on black after sign-off, instead of "bugs" on white, because their receivers used positive rather than USA-Canada negative video modulation.

When USA broadcasters transitioned to color television, the SMPTE color bars superseded the black-and-white test pattern image. In Sweden the Indian head was used in test transmissions from the Royal Institute of Technology from 1948 until November 1958 when it was replaced by the Sveriges Television test card.[1]

As television system tool

The primary and critical Indian Head Test Pattern was not a card. It was generated directly as an NTSC video signal by using an opaque metal cathode ray tube known as a monoscope [2], which had a perfectly proportioned copy of the test pattern inside, permanently deposited as a carbon image on an aluminum target plate. This perfect copy allowed all of the studio or control room video picture monitors, and home television sets, to be identically adjusted for minimum distortions such as ovals instead of circles.

Only after the monitors were adjusted was an Indian Head Test Card used. A cardboard mounted lithograph of the test pattern was typically attached to a rolling vertical easel in each TV studio, to be videographed by each studio camera during test time. Then the cameras were adjusted to appear identical on picture monitors alternately switched between the monoscope image and the test card image.

These adjustments were made on a regular basis because all of the television system electronics used hot vacuum tubes whose characteristics drifted as they aged each day.

Test patterns were also broadcast to the public daily to allow regular adjustments by home television set owners and TV shop repair technicians. The test pattern was usually accompanied by a 1,000 or 400 hertz sine wave test tone. 400 Hz is somewhat less annoying for technicians to hear for extended work periods.

As cultural icon

An actual Indian Head Test Card was only of secondary importance to television system adjustment, but many of them were saved as souvenirs or works of found art. By contrast, nearly all of the hard-to-open steel monoscope tubes were junked with their invisible Indian Head Test Pattern target plates still inside.

The original art work was completed for RCA by an artist named Brooks on August 23, 1938. The master art was improbably discovered in a dumpster by a wrecking crew worker as the old RCA factory in Harrison, NJ was being demolished in 1970. The worker kept the art for over 30 years, and then used the internet to locate and sell it to a test pattern collector.[3]

While perhaps best recalled by baby boomers for its brief albeit iconic part in the opening sequence of The Outer Limits (1963-1965), it still makes occasional television appearances. A parody with a laughing Indian was the logo for the first season of Second City Television. In an episode of Back to the Future: The Animated Series, a parody with Emmett Brown's head replaces that of the Indian. More recently, it has been used in Arrested Development when the television program "accidentally" cut to test pattern just before what would have been partial nudity (this gag may have originated in the 1967 Vilgot Sjoman film I Am Curious (Yellow)). It also features prominently on the DVD packaging art of 1989 cult comedy UHF (film) as the lenses of "Weird Al" Yankovic's glasses. A parody of this test card appears in the computer game Streets of SimCity for 5 seconds before going to the main menu, as well as making an appearance as a loading screen in the game Fallout. A tiny reproduction of the Indian test card is also found on the main control panel of the "AVD Video Processor" program.

In the 1998 film Pleasantville a modified version of the test card appears on the television screen behind the Don Knotts character. The Indian head changes its facial expression over the course of the film.

As of 2006, most television stations in the United States no longer sign off overnight, instead running infomercials or networked overnight news shows, but the Indian Head Test Card persists as a symbol of early television. It is even sold as a night-light, reminiscent of the days when a common late-night experience for all ages was to fall asleep while watching the late movie, then awake to the characteristic sinewave tone and the test card on the screen.

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