Transistorized video black clipper

Claim 1

A TRANSISTORIZED BLACK CLIPPER FOR USE WITH A VIDEO SIGNAL CONTAINING SHORT DURATION PERIODIC PULSES COMPRISING A FIRST TRANSISTOR VIDEO AMPLIFIER OF LOW OUTPUT IMPEDANCE BASE INPUT EMITTER FOLLOWER CONFIGURATION, A SECOND EMITTER FOLLOWER TRANSISTOR AMPLIFIER OF HIGH INPUT IMPEDANCE, A CAPACITOR COUPLING THE EMITTER OF THE FIRST TRANSISTOR TO THE BASE ELECTRODE OF THE SECOND TRANSISTOR PROPORTIONED TO SUSTAIN A CHARGE ON SAID BASE ELECTRODE OVER THE INTERVAL BETWEEN PULSES, A KEYED BALANCED DIODE CLAMP COUPLED TO SAID BASE ELECTRODE COMPRISING A PAIR OF SEMICONDUCTOR DIODES, KEYED DURING SAID PULSES, AND HAVING A LOW IMPEDANCE IN CONCERT WITH THE OUTPUT IMPEDANCE OF SAID FIRST AMPLIFIER PROPORTIONED FOR PERMITTING A SUBSTANTIAL CHANGE IN THE CHARGE ON SAID CAPACITOR DURING ONE OF SAID PULSES, A THIRD AMPLIFIER HAVING A TRANSISTOR COMPLEMENTARY TO THAT OF SAID SECOND AMPLIFIER AND HAVING ITS BASE D.C. COUPLED TO THE EMITTER OF SAID SECOND AMPLIFIER FOR TEMPERATURE COMPENSATION, AND A SEMICONDUCTOR DIODE SERIES CLIPPER COUPLED TO THE COLLECTOR OF SAID THIRD TRANSISTOR REFERENCED TO A VOLTAGE SOURCE THROUGH A LOW IMPEDANCE PATH, SAID TRANSISTOR OUTPUT IMPEDANCE BEING SELECTED LARGE WITH RESPECT TO THE IMPEDANCES OF SAID LAST RECITED ELEMENTS FOR EFFECTING POSITIVE CLIPPING ACTION.