Miniaturized and transistorized frequency selective amplifier circuit

Claim 1

IN A FREQUENCY SELECTIVE AMPLIFIER CIRCUIT FOR AMPLIFYING SIGNALS APPLIED THERETO, A TRANSFORMER INCLUDING A PLURALITY OF WINDINGS, A TRANSISTOR ARRANGED AS A COMMON-EMITTER AMPLIFIER AND CONNECTED ACROSS A FIRST OF SAID WINDINGS, A FREQUENCY SELECTIVE BRIDGE CIRCUIT INCLUDING ONLY RESISTANCE AND CAPACITANCE COMPONENTS AND TUNED TO A PREDETERMINED FREQUENCY, CONNECTED ACROSS A SECOND OF SAID WINDINGS AND ACROSS THE EMITER AND THE BASE OF THE TRANSISTOR, WHEREBY SIGNALS APPLIED TO THE BASE OF THE TRANSISTOR ARE AMPLIFIED TO A PREDETERMINED EXTENT AND APPLIED THROUGH THE TRANSFORMER TO THE BRIDGE CIRCUIT WHEREIN A VOLTAGE IS DEVELOPED AND FED BACK TO THE BASE OF THE TTANSISTOR AS INVERSE FEEDBACK TO REDUCE AMPLIFICATION OF THE SIGNAL BY THE TANSISTOR BELOW THE PREDETERMINED EXTENT IF THE FREQUENCY OF THE SIGNAL DOES NOT CORRESPOND TO THE FREQUENCY TO WHICH THE BRIDGE IS TUNED, AND A TRANSISTORIZED DETECTOR CIRCUIT CONNECTED ACROSS A THIRD OF SAID TRANSFORMER WINDINGS FOR RECEIVING AMPLIFIED SIGNALS FROM THE TRANSISTOR.