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FROM THE ARCHIVE OF: Dave Baldwin
In this excerpt from a 1976 Open University programme, some discussion about the uses of the familiar Test Card F pattern.
VIDEO: Open University programme discussing test cards. TX DATE: 1976. COPYRIGHT: BBC. VREF: 24195-01.
Video content
[00:00:00] PROGRAMME: the programme discusses some of the uses of the test card.
Initially, the test card is used to demonstrate the effect of adding an extra path, causing ghosting.
Tests/uses covered:
- High frequency response.
- Low frequency response.
- Non-linear effects on the video signal.
- The ends of the arrows at the edges of the test card can be used to adjust the size of broadcast picture.
- Reflection.
RELATED ARTICLE: the history of the BBC trade test transmission.
Acknowledgements
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