Radio receiver having voltage-controlled resonant circuit coupling means between stages

Claim 1

A WAVE SIGNAL INTERMODULATION ATTENUATION SYSTEM FOR A RECEIVER, INCLUDING IN COMBINATION, FIRST AND SECOND RECEIVER CIRCUIT PORTIONS HAVING OUTPUT AND INPUT CIRCUITS RESPECTIVELY, SAID FIRST RECEIVER CIRCUIT PORTION HAVING A TUNED CIRCUIT TUNED TO THE DESIRED SIGNAL, RESONANT CIRCUIT MEANS CONNECTED IN SERIES BETWEEN SAID OUTPUT AND INPUT CIRCUITS AND BEING THE SOLE INTERCOUPLING BETWEEN SAID RECEIVER CIRCUIT PORTIONS, SAID RESONANT CIRCUIT MEANS INCLUDING INDUCTANCE MEANS AND POTENTIAL VARIABLE CAPACITANCE MEANS AND HAVING VALUES OF INDUCTANCE AND CAPACITANCE RESPECTIVELY SO AS TO PROVIDE LOW IMPEDANCE AT THE FREQUENCY OF SIGNALS COUPLED BETWEEN SAID RECEIVER CIRCUIT PORTIONS, MEANS FOR APPLYING A DIRECT CURRENT POTENTIAL ACROSS SAID POTENTIAL VARIABLE CAPACITANCE MEANS WHICH POTENTIAL IS PROPORTIONAL TO THE LEVEL OF A SIGNAL TRANSLATED BY SAID SYSTEM, SAID RESONANT CIRCUIT MEANS PROVIDING A HIGHER IMPEDANCE BETWEEN SAID OUTPUT AND INPUT CIRCUITS AS SAID DIRECT CURRENT POTENTIAL VARIES WITH INCREASING SIGNAL LEVEL AND SAID RESONANT CIRCUIT MEANS IS VARIABLY RESONATE WITH RESPECT TO THE FREQUENCY OF THE DESIRED SIGNAL TO THEREBY REDUCE OVERALL INTERMODULATION EFFECTS FOR STRONG RECEIVED SIGNALS.