Test cards Test cards The Indian Head test card was a black and white television test pattern used by RCA that was introduced in 1939. The card was generated by using a special tube called a monoscope. The Indian Head could be seen when a station had closed down for the night, or an hour or so before the station signed on the air. It would often be accompanied by the United States national anthem followed by a 1,000 hertz test tone. This pattern was also used in Canada, followed with the Canadian national anthem in the evening at sign-off. ...more on Wikipedia about "Indian Head test card"
A monoscope was a special form of cathode ray tube that was used to generate, rather than display, a video signal. Each tube was only capable of generating a single video signal, hence the name. ...more on Wikipedia about "Monoscope"
The Philips PM5544 is a television pattern generator, most commonly used to provide a television station with a complex test card. It has been in use since the dawn of colour television, and is the most commonly used test card generator, with only the SMPTE bars and the BBC Test Card F coming close to its usage. The BBC even use it themselves, as Test Card G, and most other broadcasters using a 625 line system such as PAL or SECAM also use it. ...more on Wikipedia about "Philips PM5544"
The SMPTE color bars are a type of television test pattern, and is most commonly used in countries where the NTSC video standard is dominant, such as in North America. The Society of Motion Picture and Television Engineers (SMPTE) refers to this test pattern as Engineering Guideline EG 1-1990. The components of this pattern are a known standard, so comparing this pattern as received to that known standard gives video engineers an indication how an NTSC video signal has been altered by recording or transmission, and thus what compensation needs to be applied to that signal to bring it back to original condition. The pattern is also used for setting a television monitor or receiver to reproduce NTSC chrominance and luminance information correctly. ...more on Wikipedia about "SMPTE color bars"
A test card, also known as a test pattern in North America, is a television test signal, typically broadcast at times when the transmitter is active, but no program is being broadcast (often at startup and closedown). They allow vendors and viewers adjust their set for optimal functionality. They have been shown since the earliest TV broadcasts by the BBC, Baird Television and Marconi E.M.I systems. ...more on Wikipedia about "Test card"
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