Patent ID: 7821362

Claim:
A signal communication system, coupled to a signal source that receives a broadcast spectrum from an electrically or optically conductive medium, to output a filtered representation of a broadcast-frequency video signal corresponding to a selected channel of a plurality of channels of the broadcast spectrum, the system comprising: frequency-selective filter circuitry, coupled to the signal source, to receive the broadcast-frequency video signal and to output a filtered representation of the broadcast-frequency video signal, the frequency-selective filter circuitry including: a filter network, coupled to the signal source, to output the filtered representation of the broadcast-frequency video signal, the filter network including (i) a selectable center frequency of a frequency band which is associated with the selected channel and (ii) a voltage controlled capacitive element which is responsive to a voltage amplitude of a control signal; and control signal generator circuitry, coupled to the frequency-selective filter circuitry, to generate the control signal having a voltage amplitude which is associated with the selected channel, the control signal generator circuitry including: a control signal generator circuit, coupled to the filter network, to generate and output the control signal having the voltage amplitude which is associated with the selected channel; and a feedback circuit, coupled to the control signal generator circuit, to sense the voltage amplitude of the control signal, wherein the feedback circuit generates and outputs a feedback signal which is representative of the voltage amplitude sensed thereby; and wherein the control signal generator circuit responsively adjusts the voltage amplitude of the control signal when the feedback signal is different from a signal which is associated with the amplitude of the control signal.