Circuit for producing complex electric signals of predetermined amplitude and phase for controlling character forming means

Claim 1

IN A CIRCUIT FOR SUPPLYING ELECTRIC CONTROLLING SIGNALS DEFINING THE SIGNAL COMPONENTS ALONG TWO COORDINATE AXES WHICH CORRESPOND TO THE DIFFERENT SECTIONS OF THE SYMBOLS OF THE TYPEWRITER KEYBOARD TYPE TO BE FORMED, ALONG THOSE AXES, COMPRISING A GENERATOR MEANS CONNECTED TO PRODUCE IN A CONTINUOUS MANNER TWO GROUPS OF FOUR SUBSTANTIALLY SINUSOIDAL VOLTAGE SIGNALS, THE FOUR VOLTAGE SIGNALS OF ONE GROUP BEING OF A SAME BASIC FREQUENCY AND OF A SAME AMPLITUDE AND PHASE SHIFTED WITH REFERENCE TO ONE ANOTHER BY $/2, THE FOUR VOLTAGE SIGNALS OF THE SECOND GROUP BEING OF A SAME FREQUENCY SUBSTANTIALLY DOUBLE THE BASIC FREQUENCY AND OF A SAME AMPLITUDE OF SAID ONE GROUP AND PHASE SHIFTED WITH REFERENCE TO ONE ANOTHER BY $/2, A SOURCE OF AT LEAST TWO D.C. VOLTAGES OF OPPOSITE POLARITIES, AT LEAST ONE FURTHER SUBSTANTIALLY SINUSOIDAL VOLTAGE SIGNAL PRODUCES BY SAID GENERATOR MEANS AT SAID BASIC FREQUENCY AND SHIFTED BY