Hard Drive: SEAGATE: ST4026 (1990) 21MB 5.25"/FH MFM ST506

S T 4 0 2 6   ( 1 9 9 0 )    SEAGATE
NO MORE PRODUCED                                      Native|  Translation
                                                      ------+-----+-----+-----
Form                 5.25"/FH              Cylinders     615|     |     |
Capacity form/unform    21/   25 MB        Heads           4|     |     |
Seek time   / track  40.0/ 8.0 ms          Sector/track   17|     |     |
Controller           MFM / ST506           Precompensation   616
Cache/Buffer               KB              Landing Zone
Data transfer rate    0.625 MB/S int       Bytes/Sector      512
                      0.625 MB/S ext
Recording method     MFM                            operating  | non-operating
                                                  -------------+--------------
Supply voltage     5/12 V       Temperature *C                 |
Power: sleep              W     Humidity     %                 |
       standby            W     Altitude    km                 |
       idle               W     Shock        g                 |
       seek          25.5 W     Rotation   RPM      3600
       read/write         W     Acoustic   dBA
       spin-up            W     ECC        Bit
                                MTBF         h      15000
                                Warranty Month
Lift/Lock/Park     YES          Certificates                                  

Layout

SEAGATE ST4026 PRODUCT DESCRIPTION 6/26/90

  +-------------------------------------------------------+
  |                                                       |XX Data
  |                                                       |XX J2 20pin
  |                                                       |XX1
  |                                                      ++1
  |                                                      | | Drive
  |                                                      ++4 Select
  |                                                       |XX
  |                                                       |XX
  |                                                       |XX J1 34pin
  |                                                       |XX Control
  |                                                       |XX
  |                                                       |XX
  |                                  Terminator Resistor  |XX
  |                                  Pack        +-------+|  1
  |                                              +-------1|XX J3
  |                                                       |XX Power
  +-------------------------------------------------------+  1

Jumpers

SEAGATE ST4026 PRODUCT DESCRIPTION 6/26/90

Jumper Setting
==============

 Drive Select
 ------------
     +-------+
     |X o o o|  Drive 1 is selected
     |X o o o|
     +1-2-3-4+

     +-------+
     |o X o o|  Drive 2 is selected
     |o X o o|
     +1-2-3-4+

     +-------+
     |o o X o|  NEVER USED!!! (Drive Select 3)
     |o o X o|
     +1-2-3-4+

     +-------+
     |o o o X|  NEVER USED!!! (Drive Select 4)
     |o o o X|
     +1-2-3-4+

If twisted cable, use Drive Select 2.

Install

SEAGATE ST4026 PRODUCT DESCRIPTION 6/26/90

Notes on installation
=====================

Drive mounting
--------------

     horizontally             vertically
   +-----------------+   +--+             +--+ +------------------+
   |                 |   |  +-----+ +-----+  | |                  | x
   |                 |   |  |     | |     |  | x+----------------+x
 +-+-----------------+-+ |  |     | |     |  | ||x              x||
 +---------------------+ |  |     | |     |  | ||  x          x  ||
                         |  |     | |     |  | ||    x      x    ||
      x           x      |  |     | |     |  | ||      x  x      ||
 +------x------x-------+ |  +-----+ +-----+  | ||       xx       ||
 +-+------x--x-------+-+ +--+             +--+ ||     x    x     ||
   |       xx        |                         ||   x        x   ||
   |     x    x      |                         || x            x ||
   +---x--------x----+                         |x                x|
     x            x                           x++----------------++x
      UNACCEPTABLE!                                UNACCEPTABLE!

 J3   DC Power and pin connector assignments
 -------------------------------------------
      +-----J3-----+   pin 1    +12 VDC
      | 4  3  2  1 |   pin 2    +12 Volts Return
      +------------+   pin 3    + 5 Volts Return
                       pin 4    + 5 VDC