Gyrator frequency selectors with bandwidth independent of input signal level

A frequency selector is described in which the bandwidth is independent of the level of the input signal. The selector employs two channels in which the amplitude-frequency characteristics are formed by combining the signals from the outputs of the gyrators, which are part of the resonators, with the help of summing amplifiers. A working model is described. The use of resonators connected in parallel and antiphase followed by detection of the output voltage of the summing amplifiers and comparison by a dc comparator is recommended for gyrator frequency selectors. The dynamic range of the filter can be increased, and the operating band stability improved, by using detectors with low threshold voltage.