Video system, method and apparatus for incorporating audio or data in video scan intervals

A method of producing composite video signals for selectively displaying successive video fields in vertical synchronizing intervals of a displayable program, the method comprising the steps of:

• producing a plurality of horizontal traces of video field information for displaying successive video fields of the displayable program;
• interposing on selected horizontal traces of said video field information for successive fields of the displayable program digital data information following the post equalizing interval in the vertical blanking interval;
• said digital data information being interposed upon the selected horizontal scan lines within an interval during each such scan commencing not sooner than 13 microseconds after the leading edge of the horizontal synchronization pulse and ending not less than 3 microseconds before the leading edge of the succeeding horizontal synchronizing pulse.

A method of producing composite video signals for selectively displaying successive video fields in vertical synchronizing intervals of a displayable program, the method comprising the steps of:

• producing a plurality of horizontal traces of video field information for displaying successive video fields of the displayable program;
• interposing on selected horizontal traces of said video field information for successive fields of the displayable program digital data information following the post equalizing interval in the vertical blanking interval;
• said digital data information being interposed on selected horizontal scan lines as a pulse-code modulated signal within four data frames of ten bits per data frame with each first bit per data frame being a start bit of logical `1`, and with each tenth bit per data frame being a stop bit of logical `0`.

A method of producing a composite video signal for selectively displaying successive video fields of a displayable program, the method comprising the steps of:

• producing a plurality of horizontal traces of video field information for displaying successive video fields of the displayable program;
• interposing fresh audio signal information and redundant audio information in a selected sequence on corresponding selected horizontal traces of said video field information for successive video fields of the displayable program, wherein said redundant audio information includes a duplicate portion of the corresponding fresh audio information in a preceding video field;
• and interposing reference pulses on the selected horizontal traces of said video field information preceding the redundant audio information and following the fresh audio information for establishing a reference level of audio information in each horizontal trace.