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SJ Research Hard Disc File Server

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The SJ Research HDFS (Hard Disc File Server) was SJ Research's first Econet file server. It is notable for both its size and weight (it is approximately 52 x 44 x 18 cm). The HDFS could support up to 80MB MFM hard discs, a serial and parallel printer and a 20MB tape drive.

The HDFS configuration is:

The HDFS automatically date and time stamps files when saved or updated and supports disc space accounting which allows disc space limits to be set for each user. In 1986 an 80MB HDFS would have cost you £9,000 (£7,200 for education users)!


Here is a brochure describing the SJ Research HDFS .
 Here is the SJ Research Hard Disc File Server System Manager's Manual v0.22 17-7-85 .


SJ Research HDFS front

 SJ Research HDFS (front)

The front of the SJ Research HDFS has the tape drive in the bottom left, the LEDs in the top right are: Change Tape, Tape Active, Disc Active, System Failure, No Clock, Boot Error, Printer Error, Configuration and online. The mode key-switch is at the bottom right.

SJ Research HDFS right side

  SJ Research HDFS (right)

SJ Research HDFS back

  SJ Research HDFS (back)

The back of the HDFS shows:

SJ Research HDFS with cover removed

 SJ Research HDFS with top cover removed 

Removing the top cover from the HDFS shows the main circuit board.the ribbon cable on the left is connected to the tape drive and the ribbon cable at the front is connected to the hard disc.

SJ Research HDFS with circuit board removed

 SJ Research HDFS with circuit board removed

Removing the main circuit board from the HDFS shows:


SJ Research HDFS circuit board top

SJ Research HDFS circuit board (top) 

The HDFS main circuit board showing:

Here is a HiRes picture of the HDFS circuit board .

SJ Research HDFS circuit board bottom

 SJ Research HDFS circuit board (bottom)

Note that there are a number of wire patchs on the bottom of the circuit board.