Frequency-response corrective network

A corrective network for obtaining a desired overall frequency response, comprising a symmetrical source having two output terminals and a tap located intermediate the output terminals;

• a dropping resistor having one end connected to one of the output terminals of the source, and another end;
• a load impedance connected between the other end of the dropping resistor and the tap;
• and a plurality of tunable, non-active resonant circuit stages each including a differential capacitor having two stator plate terminals each connected to a respective one of the output terminals of the source for receiving input signals from the latter, and a rotor plate terminal, each stage also including a resistor and an inductor operatively connected between the rotor plate terminal and the other end of the dropping resistor, each differential capacitor of every stage being adjustable for supplying output signals to the load impedance such that respective different portions of the frequency spectrum of the input signals are modified to obtain the desired overall frequency response.

A corrective network for obtaining a desired overall frequency response, comprising a source having two output terminals and a tap located intermediate the output terminals;

• and a plurality of tunable, non-active resonant circuit stages each including a differential capacitor having two stator plate terminals each connected to a respective one of the output terminals of the source for receiving input signals from the latter, and a rotor plate terminal, each stage also including a resistor and an inductor operatively connected between the rotor plate terminal and the source, each differential capacitor of every stage being adjustable so as to generate output signals such that respective different portions of the frequency spectrum are modified.