                              ST - 157A

       UNFORMATTED CAPACITY (MB) ________________N/A
       FORMATTED CAPACITY (26 SECTORS) (MB) _____43.0
       ACTUATOR TYPE ____________________________STEPPER
       TRACKS ___________________________________3,234
       CYLINDERS ________________________________539
       HEADS ____________________________________6
       DISCS ____________________________________3
       MEDIA TYPE _______________________________THIN FILM
       RECORDING METHOD _________________________RLL
       TRANSFER RATE (mbits/sec) ________________7.5
       INTERFACE ________________________________AT BUS
       TPI (TRACKS PER INCH) ____________________824
       BPI (BITS PER INCH) ______________________20,280
       AVERAGE ACCESS (ms) ______________________40/28*
       SINGLE TRACK SEEK (ms) ___________________8
       MTBF (power-on hours) ____________________50,000
       POWER REQUIREMENTS: +12V START-UP (amps) _2.0
                           +12V TYPICAL (amps) __0.35
                           +5V TYPICAL (amps) ___0.9
                           TYPICAL (watts) ______9
                           MAXIMUM (watts) ______29
       BUFFERED STEP PULSE RATE (micro sec) _____3-200
       WRITE PRECOMP (cyl) ______________________N/A (540)
       REDUCED WRITE CURRENT (cyl) ______________N/A (540)
       LANDING ZONE (cyl)________________________AUTO PARK
       IBM AT DRIVE TYPE ________________________?**

       *ST157R-0/ST157R-1
       **MAY REQUIRE PARTITIONING SOFTWARE
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