Closed circuit can refer to:
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Closed-circuit television
Closed-circuit television (CCTV), also known as video surveillance, is the use of video cameras to transmit a signal to a specific place, on a limited set of monitors. It differs from broadcast television in that the signal is not openly t ...
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Closed-circuit radio A closed-circuit radio is a radio that emits over a very small range, typically a college campus. This system can be achieved from two ways:
*By tying into the PA System
*By using existing power lines
Electric power transmission is the bulk mov ...
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Rebreather – breathing sets
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''Closed Circuit'' (1978 film), a 1978 Italian film
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''Closed Circuit'' (2013 film), a 2013 British thriller film
*An
electric circuit is a "closed circuit" if it contains a complete path between the positive and negative terminals of its power source
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''Closed Circuit'' (album), a 2001 album by New Zealand composer Peter Jefferies
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