It features a drawing of a Native American wearing a headdress surrounded by numerous graphic elements designed to test different aspects of broadcast display.
Each element of the card was designed to measure a specific technical aspect of television broadcast so that an experienced engineer could, at a glance, identify problems.
The card contains elements used to measure aspect ratio,[a] perspective, framing, linearity, frequency response, differential gain, contrast, and brightness.
The pattern began with the Indian-head portrait created in August 1938 by an artist named Brooks using pencil, charcoal, ink and zinc oxide.
First, they would use a monoscope in which the pattern was permanently embedded, which was capable of producing the image with a high degree of consistency due to the device's simplicity.
The tube has a perfectly proportioned copy of the test pattern master art (or a modified variant with the station ID replacing the Indian-head portrait, such as those used by KRLD-TV,[2] WBAP-TV[3] and WKY-TV[4]) inside, permanently deposited as a carbon image on an aluminum target plate or slide.
Some Pioneer GGV1069 LaserDisc reference discs released for the NTSC market included a variant of the card, but modified with a gray-colored grid and a drawing of a Japanese lion-dog replacing the Indian-head portrait.
[11][12] It was sold as a night-light from 1997 to 2005 by the Archie McPhee company,[13] reminiscent of the times when a fairly common late-night experience was to fall asleep while watching the late movie, only to awaken to the characteristic sine wave tone accompanying the Indian-head test pattern on a black-and-white TV screen.
[14] Nearly all of the hard-to-open, steel-shielded monoscope tubes were junked with their Indian-head test pattern target plates still inside, but many of the board-mounted lithographs survive.
The master art for both the portrait and the pattern design was discovered in a dumpster by a wrecking crew worker as the old RCA factory in Harrison, New Jersey was being demolished in 1970.
This version eschewed the Indian head drawing with the TNT-9 station ID on top, similar to the aforementioned KRLD-TV, WBAP-TV and WKY-TV variants.