The IBM 728 was an IBM 7 series magnetic tape drive. It was used on the SAGE AN/FSQ-7 computer. It was physically similar to the IBM 727, but with significantly different specifications.
Tracks6 Data, 1 synchronizationchar/inch248 char/inchWords6 chars (32 data bits, 1 odd parity bit, 3 end of file bits) word/inch41.33 word/inchEnd of record gap0.75 inch - 186 chars - 31 wordsTape speed75 inch/sRewind speed500 inch/s (average)Transfer rate18,750 char/s - 3,125 word/sStart time5 msStop time5 msWidth of tape1/2 inchLength of reelCompositionMylar or cellulose acetate base Tape Word Bit Positions
-----------------------------> Tape travel LS L6 L12 R2 R8 R14 L1 L7 L13 R3 R9 R15 L2 L8 L14 R4 R10 P SYN SYN SYN SYN SYN SYN L3 L9 L15 R5 R11 EOF L4 L10 RS R6 R12 EOF L5 L11 R1 R7 R13 EOF -----------------------------> Tape travel
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