Tape drive and indexing system

Claim 1

THE COMBINATION OF A COMPUTER HAVING ERROR DETECTING CIRCUITRY IN THE INPUT CIRCUIT THEREOF, AND A RECORDINGREPRODUCING DEVICE THAT INCLUDES A TAPE DRIVE SYSTEM FOR EFFECTING THE INCREMENTAL ADVANCE OF A TAPE MEDIUM ALONG A PREDETERMINED PATH OF TRAVEL AND RELATIVE TO A READ-WRITE HEAD ASSEMBLY OF THE RECORDING-REPRODUCING DEVICE, COMPRISING: A FIRST DRIVE UNIT DISPOSED ALONG THE PATH OF TRAVEL OF THE TAPE FOR ADVANCING THE TAPE IN INCREMENTAL STEPS CORRESPONDING SUBSTANTIALLY TO INDIVIDUAL BIT POSITIONS AT A FIRST ADVANCING RATE; A SECOND DRIVE UNIT DISPOSED ALONG THE PATH OF TRAVEL OF THE TAPE ADJACENT TO SAID FIRST DRIVE UNIT FOR ADVANCING THE TAPE IN STEPS CORRESPONDING TO THE LENGTH OF THE CHARACTER INFORMATION RECORDED THEREON AT A SECOND ADVANCING RATE; FIRST CIRCUIT MEANS RESPONSIVE TO A FIRST SIGNAL FOR ACTUATING SAID FIRST DRIVE UNIT TO EFFECT THE INITIATION OF THE BIT BY BIT ADVANCE OF THE TAPE; AND SECOND CIRCUIT MEANS ELECTRICALLY CONNECTED TO THE HEAD ASSEMBLY OF THE RECORDER-REPRODUCER AND RESPONSIVE TO SIGNAL INFORMATION DERIVED FOR RENDERING THE FIRST DRIVE UNIT INEFFECTIVE AND FOR RENDERING SAID SECOND DRIVE UNIT EFFECTIVE DURING WHICH PERIOD CHARACTER INFORMATION IS DERIVED FROM THE TAPE.