Color television display indexing system

Claim 1

IN COMBINATION WITH A SOURCE OF VIDEO SIGNALS AND A CATHODE RAY TUBE WHEREIN AN ELECTRON BEAM POSITIONALLY CONTROLLED FROM A DEFLECTION CIRCUIT SUCCESSIVELY SCANS HORIZONTALLY A PLURALITY OF VERTICAL, PARALLEL, LATERALLY SEPARATED INDEXING STRIPES TO PRODUCE SECONDARY EMISSION CURRENT PULSES AT AN INDEXING RECURRENCE FREQUENCY, THE ACTUAL SCANNING VELOCITY ESTABLISHED BY THE DEFLECTION CIRCUIT INHERENTLY VARYING ABOUT A NOMINAL FIXED VALUE WHEREBY THE INSTANTANEOUS PHASE OF SAID PULSES VARIES ACCORDINGLY, THE BEAM INTENSITY BEING CONTROLLED FROM A GRID CIRCUIT, A PILOT OSCILLATOR COUPLED TO SAID GRID CIRCUIT TO MODULATE SAID BEAM INTENSITY AT A FIXED PILOT FREQUENCY WHEREBY AN INDEXING SIGNAL CONSTITUTED BY SAID PULSES MODULATED ON A FIRST CARRIER AT SAID PILOT FREQUENCY IS PRODUCED, THE UPPER AND LOWER SIDEBANDS OF SAID FIRST CARRIER RESPECTIVELY REPRESENTING THE SUM AND DIFFERENCE OF SAID PILOT AND INDEXING FREQUENCIES, A CIRCUIT COMPRISING FIRST MEANS RESPONSIVE TO SAID INDEXING SIGNAL TO DERIVE THEREFROM A SINGLE SIDEBAND SIGNAL AT SAID INDEXING FREQUENCY; SECOND MEANS COUPLED TO SAID DEFLECTION CIRCUIT TO DERIVE THEREFROM A CONTROL VOLTAGE, THE MAGNITUDE OF SAID VOLTAGE INCREASING WITH INCREASING DIFFERENCE BETWEEN SAID NOMINAL AND ACTUAL VELOCITIES AND BEING ZERO WHEN SAID TWO VELOCITIES ARE EQUAL, SAID VOLTAGE HAVING ONE POLARITY WHEN THE ACTUAL VELOCITY IS LARGER THAN SAID NOMINAL VELOCITY AND HAVING OPPOSITE POLARITY WHEN THE NOMINAL VELOCITY IS LARGER THAN THE ACTUAL VELOCITY; AND PHASE SHIFTING AND MIXING CIRCUIT MEANS COUPLED AT ITS INPUT TO SAID SOURCE AND SAID FIRST AND SECOND MEANS TO DERIVE FROM SAID VIDEO SIGNALS, SAID SIDEBAND SIGNAL AND SAID CONTROL VOLTAGE, AN OUTPUT SIGNAL CONSTITUTED BY SAID VIDEO SIGNALS MODULATED ON A SECOND CARRIER AT SAID INDEXING FREQUENCY, THE PHASE OF SAID SECOND CARRIER BEING SHIFTED IN LIKE AMOUNT BUT IN OPPOSITE DIRECTION TO SAID INSTANTANEOUS PHASE VARIATIONS, SAID OUTPUT SIGNAL BEING SUPPLIED TO SAID GRID CIRCUIT.