Sequence indicating circuits

Claim 1

APPARATUS FOR PRODUCING A REGISTRATION OF THE SEQUENCE IN WHICH FIRST AND SECOND PRESELECTED INDICIA ARE DETECTED, COMPRISING FIRST AND SECOND COMPARATOR STORAGE ELEMENTS EACH HAVING FIRST AND SECOND STABLE STATES, MEANS FOR INITIALLY SETTING SAID COMPARATOR STORAGE ELEMENTS IN A SELECTED ONE OF SAID STATES, FIRST AND SECOND INPUT MEANS FOR EACH OF SAID COMPARATOR STORAGE ELEMENTS, FIRST SENSING MEANS RESPONSIVE TO SAID FIRST INDICIA AND OPERABLE TO ENERGIZE SAID FIRST COMPARATOR INPUT MEANS, SECOND SENSING MEANS RESPONSIVE TO SAID SECOND INIDCIA AND OPERABLE TO ENERGIZE SAID SECOND COMPARTOR INPUT MEANS, SAID FIRST COMPARATOR INPUT MEANS BEING OPERABLE WHEN ENERGIZED TO SWITCH SAID FIRST COMPARATOR STORAGE ELEMENT TO SAID SECOND STATE AND SAID SECOND COMPARATOR STORAGE ELEMENT TO SAID FIRST STATE, SAID SECOND COMPARTOR INPUT MEANS BEING OPERABLE WHEN ENERGIZED TO SWITCH SAID FIRST COMPARATOR STORAGE ELEMENT TO SAID FIRST STATE AND SAID SECOND COMPARATOR STORAGE ELEMENT TO SAID SECOND STATE, SAID FIRST AND SECOND COMPARATOR INPUT MEANS BEING ADAPTED TO EXERT NO SWITCHING INFLUENCE ON SAID COMPARATOR STORAGE ELEMENTS WHEN COINCIDENTALLY ENERGIZED, WHEREBY THE RESULTANT RELATIVE STATES OF SAID FIRST AND SECOND COMPARTOR STORAGE ELEMENTS INDICATE THE TIME SEQUENCE IN WHICH SAID FIRST AND SECOND INDICIA ARE DETECTED BY SAID FIRST AND SECOND SENSING MEANS, FIRST, SECOND AND THIRD REGISTER STORAGE LEMENTS EACH HAVING FIRST, SECOND AND THIRD REGISTER STORAGE FIR INITIALLY SETTING SAID REGISTER STORAGE ELEMENTS IN SAID FIRST STATE, AND FIRST AND SECOND INPUT MEANS FOR EACH OF SAID REGISTER STORAGE ELEMENTS, SAID FIRST COMPARATOR STORAGE ELEMENT BEING OPERABLE WHEN RESULTANTLY IN SAID SELECTED ONE OF SAID FIRST AND SECOND STABLE STATES TO ENERGIZE SAID FIRST REGISTER INPUT MEANS, SAID SECOND COMPARATOR