Patent ID: 7570946
Filing Date: 2009-08-04
Classification: H03G,H04N

Abstract:
1. A method for determining the signal strength at an input of a tuner, an amplification characteristic of an amplification section for receiving and amplifying an input signal and outputting an output signal of the tuner being measured and stored depending on the input signal frequency, and the stored characteristic then being used during the operation of the tuner to calculate the signal strength at the tuner's input from the tuner's output signal; adjusting a gain of the amplification section by a tuner automatic gain control (AGC) circuit adapted to receive a tuner AGC feedback voltage, storing data corresponding to two or more tuner AGC reference gain curves measured at two or more corresponding input frequencies; and storing each tuner AGC reference gain curve in a corresponding plurality of selected memory locations, each of the selected memory locations corresponding to an tuner AGC gain reduction level and storing therein a measured tuner AGC feedback voltage when the tuner AGC circuit has the corresponding tuner AGC gain reduction and when the input signal has the corresponding input frequency.