Power cutting device for terminal units of CATV system
First Claim
1. In a CATV system in which a central facility is connected through cables to a plurality of terminal units so that various television programs are transmitted from the central facility through the cables to the terminal units, said television sets being supplied with power from a power supply, the improvement comprising a system for shutting off power to selected terminal units to insure that the selected terminal units can not be used, said system comprising:
- a down-data transmitter provided in said central facility for periodically sending a down-data signal containing at least a power cutting instruction and an address number of said terminal unit, a down-data receiver provided in each of said terminal units for receiving said down-data signal and a power cutting device provided in each of said terminal units, said power cutting device being responsive to said data received by said down-data receiver to cut the power supply to said television sets when the address information contained in said down-data signal is coincident with its own address.
1 Assignment
0 Petitions
Accused Products
Abstract
In a CATV system, power supplies of television sets associated with all terminal units are cut in response to an instruction contained in a down-data signal supplied by a central facility of the system. It is possible to cut the power supplies of the television sets, selectively and periodically, by incorporating address informations in the down-data signal.
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Citations
3 Claims
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1. In a CATV system in which a central facility is connected through cables to a plurality of terminal units so that various television programs are transmitted from the central facility through the cables to the terminal units, said television sets being supplied with power from a power supply, the improvement comprising a system for shutting off power to selected terminal units to insure that the selected terminal units can not be used, said system comprising:
a down-data transmitter provided in said central facility for periodically sending a down-data signal containing at least a power cutting instruction and an address number of said terminal unit, a down-data receiver provided in each of said terminal units for receiving said down-data signal and a power cutting device provided in each of said terminal units, said power cutting device being responsive to said data received by said down-data receiver to cut the power supply to said television sets when the address information contained in said down-data signal is coincident with its own address. - View Dependent Claims (2, 3)
Specification