Patent ReferencesDedicated channel interactive cable television system Interactive cable television system Patent #: 4264925 InventorApplicationNo. 06/390877 filed on 06/22/1982US Classes:725/139, Receiver (e.g., set-top box)348/484Sound signalExaminersPrimary: Martin, John C.Assistant: Coles, Edward L. Attorney, Agent or FirmInternational ClassH04N 7/10 (20060101)AbstractInteractive programming may be provided by the system (26) of the present invention which can enable both manual and automatic selection of various interactive responses from simultaneously transmitted programming on different channels. In a cable television system (20), the channels used to transmit the interactive programming are the midband channels with the selected response being treated by the system converter (26) to convert the individually selected response to a common assigned television channel frequency for ultimate reception and display on the subscriber's television (24, 22). Automatic selection may then be accomplished by the provision of a selection signal from the logic network (48) to a local oscillator (52) which, in turn, generates a beat frequency to be mixed in a mixer (54) with the various midband channel frequencies to convert the selected midband channel frequency to the assigned television channel frequency. The selection signal is either manually selected as a result of the choice or selection manually input by the subscriber via a keyboard (50) or automatically generated as a result of the pulse count value accumulated in memory (64, 65, ) based on the weighted signal value of prior responses. Various band pass filters (36, 58, 60) and switches (34, 56) are employed to pass the appropriate signals in the interactive and conventional programming modes of the system (26). | |