| 摘要 |
<p>Off premises cable television interdiction apparatus comprises a microprocessor actuation and control means (300) for actuating and controlling a plurality of frequency agile voltage controlled oscillators (341). The voltage controlled oscillators selectively jam only unauthorized premium programming transmitted in the clear from a head end to a particular subscriber. Each voltage controlled oscillator is allocated a continuous band of frequencies consistent with the elimination of jamming signal frequency hamonics which may disturb authorized programming at a higher channel frequency. The microprocessor actuation and control means provides a calibration mode and a normal mode of operation. During the normal mode of operation, a frequency hopping rate on the order of four thousand hertz is achievable. The method of interdiction comprises the steps of generating and storing voltage control words for operating the oscillators consistent with a head end selected jamming factor for a particular channel to be jammed and addressably transmitting and storing premium programming authorization data.</p> |
