Pulse generator for producing a synchronous pulse sequence with alternating voltage of adjustable phase angle

Claim 1

A pulse generator for producing a synchronous pulse sequence with alternating voltage and adjustable phase angle, said pulse generator comprising a first diode; a first capacitor connected in series circuit arrangement with said first diode; a first transistor having emitter, collector and base electrodes, a control path and an emitter-collector path connected in parallel with said series circuit arrangement; a first resistor connected at one end to a common point in the connection between said series circuit arrangement and the emitter-collector path of said first transistor, said first diode having a polarity path whereby said first capacitor is charged through said first resistor when said first transistor is in its nonconductive condition; a second resistor; a second diode connected in series circuit arrangement with said second resistor, said last-mentioned series circuit arrangement being connected in parallel with said first diode, said second diode having a polarity whereby said first capacitor may discharge through said second diode, said second resistor and the emitter-collector path of said first transistor; a source of unidirectional control voltage, said source of control voltage and said second resistor being connected in parallel with the control path of said first transistor, said source of control voltage having output terminals providing a rippled control direct voltage from a source of alternating voltage; coupling means coupling the other end of the first resistor to an output terminal of the source of control voltage; a source of reference direct voltage; a third diode, the emitter-collector path of said first transistor being connected to said source of reference direct voltage in parallel through said third diode, said third diode having a polarity whereby the voltage to which said first capacitor will charge is limited to the magnitude of said reference direct voltage; a second transistor having emitter, collector and base electrodes and a control path; another resistor connected between the collector electrode of the second transistor and the coupling means thereby connecting said second transistor to said output terminal of said source of control voltage; a fourth diode connected in series circuit arrangement with the control path of said second transistor, said fourth diode passing a control current for switching said second transistor to its conductive condition; and a fifth diode, the emitter-collector path of said first transistor being connected to said last-mentioned series circuit arrangement in parallel through said fifth diode, said fifth diode having a polarity whereby the control current will drain off through said fifth diode when the emitter-collector voltage of said first transistor is less than a specific magnitude determined by the threshold magnitude of said fourth diode and the control path of said second transistor.