DEC's PDP range of computers were small 16 bit machines that had become the mainstay of the small laboratory, especially in universities. The VAX was developed as a 32 bit machine with virtual addressing. It was regarded as a supermini computer having a lot more power than the PDP 11s but not being as expensive as a mainframe computer. The 11/780s, incorporating a networking system called DECNET, were often connected in one of the earliest forms of distributed networks.

The VAX was bought by the Department of Defence in 1984 to replace a PDP 11/40. The PDP 11 was not capable of handling the amount of data that was being collected, or producing the type of graphical result they required. The VAX was purchased after careful comparison with other systems and was eventually chosen over other systems because as well as fulfilling all the requirements it had become an industry standard. It was delivered to the Department of Defence at Wharf 17 in Pyrmont but not installed for 9 months while the air conditioning problems were sorted out. It has been used continuously for data processing on a number of projects. By the 1990s many of the tasks previously done on the VAX could be done much faster on SUN work stations. This has coincided with a general push toward personal computing within the organisation. Despite this movement the VAX 11/780 is to be replaced with a VAX 3100.

This machine also incorporates an array processor. Vector array processors allow for very fast processing of complicated mathematical expressions and can greatly speed the analysis of the huge amounts of data involved in signal processing. The system also incorporates a tektronics high resolution graphics terminal which was able to produce high resolution 3D modelling of processed data. Much of this type of data went to the Navy but some of the work that has been done will be used by commercial enterprises.

Adaptor cabinet, Unibus, VAX11/780 computer, metal/ plastic, Digital Equipment Corporation, USA, 1984.

Large metal rectangular cabinet, blue on top with beige door at front and dark grey door at back. The other sides have no housing and show steel panels where additional units bolt on. Grey door has a clear plastic pocket attached containing a leaflet (-2) with user information, the leaflet being a white card printed in black and orange.

Inside the front of the cabinet are circuit boards concealed by four black plastic sliding screens, each screen has a horizontal orange stripe. Directly below are two power boxes, that extend to the back of the unit, with identical layout displaying lights for "Power normal/Plug in regulator failure/over current/over voltage/Power inverter failure/over temp" Below these boxes is the power control panel.

Inside the back of the cabinet is a yellow caution label, several ribbon cables circuit units and three orange 'DANGER' labels. Many of the cables have bar codes attached.

Designed: Digital Equipment Corporation; United States of America

Made: Digital Equipment Corporation; United States of America; 1984


Used: Department of Defence; Sydney

Manufacturers specifications printed on a paper label, on the top left hand corner of the rear door, "digital/MODEL H9652-HB/SN: FX02062/Hz 50/60/W/V[tilde]240/416 3PH/A 12 A/P 3W+ N+O/UL (incased in a circle) /708A/LISTED/E.D.P EQUIP/ CSA (incased in a circle)" along the end of this lable is the number "3617674-01".
The same lableeis attached to the inside of the back of the cabinet housing.
Inside the back door is a paper label printed with the model number, "digital MODEL RH700-FB/SN: FXO2072".
Inside the front of the housing on the left hand power supply box, is a paper label with manufacturers specification printed in black, "P/N H7100-B UA REV D(D hand written over correction fluid)/C.S. REV ECO 00004/MFG.NI/digital" Surface of label is covered with several black and red stamps.
The right hand power supply box has a paper label with manufacturers specifications printed in black, "P/N H7100-B UA REV H/C.S. REV ECO 00007/MGF BT 74317 403/digital" The surface of this label is covered with several black stamps.
Each of the power supply boxes has printed in the top right hand corner "digital/H7100B/240v[at symbol]6A/50/60 Hz".

95/105/2

1540 mm

680 mm

770 mm