Transistor amplifier-oscillator with a feedback switching circuit

Claim 1

AN AMPLIFIER-OSCILLATOR COMPRISING, A FIRST TRANSISTOR HAVING A FIRST EMITTER, A FIRST BASE, AND A FIRST COLLECTOR, A SECOND TRANSISTOR HAVING A SECOND EMITTER, A SECOND BASE, AND A SECOND COLLECTOR, FIRST AND SECOND RESISTORS, SAID FIRST AND SECOND EMITTERS BEING CONNECTED THROUGH SAID FIRST AND SECOND RESISTORS RESPECTIVELY TO A COMMON RETURN CIRCUIT, A FIRST IMPEDANCE CIRCUIT CONNECTED THEREBETWEEN SAID FIRST EMITTER AND SAID SECOND EMITTER TO PROVIDE A FEEDBACK CIRCUIT BETWEEN SAID TRANSISTORS, A SECOND IMPEDANCE CIRCUIT, A SUPPLY TERMINAL FOR SUPPLYING DIRECTCURRENT OPERATING VOLTAGE RELATIVE TO SAID COMMON RETURN CIRCUIT, SAID FIRST COLLECTOR BEING CONNECTED TO SAID SECOND BASE, SAID JOINED COLLECTOR AND BASE BEING CONNECTED THROUGH SAID SECOND IMPEDANCE CIRCUIT TO SAID SUPPLY TERMINAL, A THIRD RESISTOR, SAID SECOND COLLECTOR BEING CONNECTED THROUGH SAID THIRD RESISTOR TO SAID SUPPLY TERMINAL, MEANS FOR BIASING SAID FIRST BASE TO CAUSE SAID FIRST TRANSISTOR TO OPERATE OVER THE RELATIVELY LINEAR PORTION OF ITS CHARACTERISTIC CURVE, A SIGNAL INPUT TERMINAL COUPLED TO SAID FIRST BASE, A SIGNAL OUTPUT AND A GENERATOR OUTPUT COUPLED TO SAID SECOND TRANSISTOR, SAID SECOND IMPEDANCE HAVING A CRITICAL VALUE ABOVE SAID AMPLIFIER-OSCILLATOR IS SELF-EXCITED AND BELOW WHICH IT OPERATES AS AN AMPLIFIER, AND SWITCHING MEANS CONNECTED TO SAID SECOND IMPEDANCE CIRCUIT OPERABLE TO ONE POSITION FOR SELECTING FOR SAID SECOND IMPEDANCE CIRCUIT A VALUE OF IMPEDANCE LOWER THAN SAID CRITICAL VALUE AND OPERABLE TO ANOTHER POSITION FOR SELECTING FOR SAID SECOND IMPEDANCE CIRCUIT A VALUE OF IMPEDANCE HIGHER THAN SAID CRITICAL VALUE.