Tuning system

Claim 1

A SIGNAL SEEKING SYSTEM FOR TUNING TELEVISION RECEIVERS OF THE TYPE INCLUDING TUNING MEANS FOR SCANNING THE FREQUENCY SPECTRUM AND SELECTING ANY ONE OF A PLURALITY OF TELEVISION SIGNALS AND CONVERTING THE MODULATED PICTURE AND SOUND CARRIER SIGNALS OF A SELECTED TELEVISION SIGNAL TO CORRESPONDINGLY MODULATED PICTURE AND SOUND INTERMEDIATE FREQUENCY SIGNALS, AND AN INTERMEDIATE FREQUENCY AMPLIFIER COUPLED TO SAID TUNING MEANS AND HAVING A PREDETERMINED BANDPASS CHARACTERISTIC, SAID RECEIVER BEING CORRECTLY TUNED WHEN SAID PICTURE AND SOUND CARRIER SIGNALS ARE RESPECTIVELY CONVERTED TO INTERMEDIATE FREQUENCY SIGNALS OF FIRST AND SECOND PREDETERMINED FREQUENCIES RESPECTIVELY BOTH WITHIN SAID BANDPASS CHARACTERISTIC, COMPRISING IN COMBINATION: DRIVING MEANS COUPLED TO DRIVE SAID TUNING MEANS TO SCAN THROUGH THE SAID FREQUENCY SPECTRUM; CONTROL CIRCUIT MEANS COUPLED TO DEENERGIZE SAID DRIVING MEANS TO STOP SAID TUNING MEANS WHEN SAID CONTROL CIRCUIT MEANS ARE ACTUATED BY A CONTROL SIGNAL; FIRST CIRCUIT MEANS COUPLED TO SAID INTERMEDIATE FREQUENCY AMPLIFIER FOR SENSING WHEN ONE OF SAID PICTURE AND SOUND I-F CARRIER SIGNALS IS AT ONE OF SAID PREDETERMINED FREQUENCIES; SECOND CIRCUIT MEANS COUPLED TO SAID I-F AMPLIFIER FOR DEVELOPING A CONTROL VOLTAGE WHENEVER THE OTHER OF SAID I-F CARRIER SIGNALS FALLS WITHIN SAID BANDPASS CHARACTERISTIC AT THE SAME TIME SAID ONE I-F CARRIER SIGNAL IS AT SAID ONE PREDETERMINED FREQUENCY; GATE CIRCUIT MEANS COUPLED TO SAID FIRST AND SECOND CIRCUIT MEANS AND RESPONSIVE TO SAID CONTROL VOLTAGE DEVELOPED IN SAID SECOND CIRCUIT MEANS TO PASS SAID ONE I-F CARRIER SIGNAL; AND MEANS COUPLED BETWEEN SAID GATE CIRCUIT MEANS AND SAID CONTROL CIRCUIT MEANS FOR DEVELOPING A CONTROL SIGNAL WHEN THE TYPE OF MODULATION IN SAID ONE I-F CARRIER SIGNAL APPLIED THERETO IS INDICATIVE OF THE DESIRED TYPE OF MODULATION FOR SAID ONE PREDETERMINED FREQUENCY WHEREBY SAID CONTROL CIRCUIT MEANS ARE ACTUATED BY SAID CONTROL SIGNAL TO STOP SAID TUNING MEANS AT A DESIRED TELEVISION SIGNAL.