Patent ID: 7983638

Claim:
A method of tuning a signal channel comprising: (a) selecting a signal channel to be tuned; (b) tuning the selected signal channel by applying a filter control signal to an electronically tunable input filter of a signal tuner, the filter control signal causing a passband frequency bandwidth of the electronically tunable input filter to encompass an expected frequency of the signal channel to be tuned; (c) monitoring a performance measurement of the tuned signal channel; (d) generating a first control signal based on monitored performance measurement; (e) retuning the selected signal channel by applying the first control signal to the electronically tunable input filter, the first control signal adjusting the passband frequency bandwidth of the electronically tunable input filter, wherein the first control signal is applied to a first variable reactance shunted with respect to an input and an output of the electronically tunable input filter, and to a second variable reactance in series with the input and the output, and wherein the first and second variable reactances comprise respective first and second varactors and wherein the first control signal comprises a first control voltage that is applied to the first varactor through a voltage scaling circuit that is operative to provide a fixed increase in the passband frequency bandwidth of the electronically tunable input filter upon receipt of a scaling signal; and (f) repeating steps (c), (d) and (e) until the adjusted passband frequency bandwidth of the electronically tunable input filter encompasses the frequency of the selected signal channel as received at an approximate center frequency of the adjusted passband frequency bandwidth.