Wired broadcasting systems
US4367557A · kind A · utility
Inventors
Key dates
| Filing date | May 25, 1979 |
| Grant date | Jan 4, 1983 |
| Priority date | — |
| Expiry date | May 25, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04K2203/14
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Subscriber access to the television transmissions of a cable TV system or other wired program transmission is governed by switching means in the remotely controlled unit to which the subscriber's receiver is connected, which switching means is enabled or disabled in response to information coded on the power flow which energizes the controlled unit. The power to the controlled unit may be coded at the cable TV power supply in response to a separate modulated RF carrier signal transmitted to all power supply units from the cable television broadcast central station, or other central location. Stated in other words, a program control center generates binary coded instructions including address words which are conveyed in a wired signal transmission system to multiple subscriber stations by encoding in a special way the output of a power supply used to supply energization to portions of the system. Upon comparison of the addresses, each station addressed is directed remotely by the coded instructions to achieve any of a plurality of switching functions, including the selective connection of program materials to the subscriber's outlet.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.