Variable amplitude self-rectifying oscillator and d. c. amplifier

Claim 1

AN OSCILLATOR-AMPLIFIER COMPRISING: A CONTROLLED VARIABLE AMPLITUDE SINUSOIDAL OSCILLATOR INCLUDING A FIRST TRANSISTOR HAVING A BASE-EMITTER JUNCTION AND COLLECTOR WITH A TUNED CIRCUIT CONNECTED TO SAID COLLECTOR AND A FEEDBACK CIRCUIT HAVING AN OUTPUT, SAID FEEDBACK CIRCUIT INDUCTIVELY COUPLED TO SAID TUNED CIRCUIT PROVIDING A SINUSOIDAL FEEDBACK SIGNAL AT SAID OUTPUT, SAID FEEDBACK CIRCUIT FURTHER INCLUDING A VARIABLE IMPEDANCE ELEMENTS THE VARIATION OF WHICH IS EFFECTIVE TO CHANGE THE MAGNITUDE OF SAID SINUSOIDAL FEEDBACK SIGNAL; A DIRECT CURRENT AMPLIFIER INCLUDING AN INPUT AND A SECOND TRANSISTOR HAVING A BASE-EMITTER JUNCTION; MEANS ELECTRICALLY CONNECTING SAID OUTPUT OF SAID FEEDBACK CIRCUIT TO SAID INPUT OF SAID DIRECT CURRENT AMPLIFIER AND TO SAID BASE-EMITTER JUNCTION OF SAID FIRST TRANSISTOR; SAID BASE-EMITTER JUNCTION OF SAID FIRST TRANSISTOR PRESENTING A LOW IMPEDANCE TO ONE PHASE OF SAID FEEDBACK SIGNAL TO CAUSE SAID FIRST TRANSISTOR TO CONDUCT TO SUSTAIN THE OSCILLATIONS OF SAID OSCILLATOR; AND SAID BASE-EMITTER JUNCTION OF SAID SECOND TRANSISTOR PRESENTING A LOW IMPEDANCE TO THE OTHER PHASE OF SAID FEEDBACK SIGNAL TO CAUSE SAID SECOND TRANSISTOR TO CONDUCT TO PROVIDE A DIRECT CURRENT OUTPUT SIGNAL WHICH IS PROPORTIONAL TO THE AMPLITUDE OF OSCILLATIONS OF SAID OSCILLATOR.