The Jim Austin Computer Collection

ACT Sirius 1


 

ACT Sirius 1

 First machine sold by Applied Computer Techniques (ACT) before selling the well known Apricot systems. One of the machines that was not ‘IBM PC’ compatible. The machine was known as the Victor 9000 in the US.

This machine came from Trinity and All Satins College in Leeds, UK.

Working machine (Screen jitters a bit)

Machine date: June 23rd 1982.

Made in the USA

Serial number: M0012527

Back and Green monitor

Twin floppy’s (no Hard disk).

With manuals:

            Introduction to the SIRIUS 1 Computer

            Sirius 1 User Guide for MS-DOS

            Sirus 1 Reference Manual for BASIC-86

MS-DOS/MS-BASIC Version 1.25a bios 2.6

CPM/M-86 v 1.1/2.4 Rev D

Wordstar mailmerge V 3.3

dBase II v2.4

dBase III plus

 

Specifications (From ACT Sirius 1 User group)

Processor Unit

  • 8088 16-bit microprocessor
  • 128 or 256k bytes RAM (standard)
  • 335ns cycle time, 64k Bits Dynamic RAM chips
  • Four - Expansion slots (internal) for plug-in card options
  • Two - RS232 serial comms ports. Standard 25 female connectors
  • One - Centronics parallel printer port
  • Two - 8 bit parallel User Ports (50 pin ribbon connector on CPU board
  • Memory expansion to 896k bytes
  • 8k bytes of ROM (boot and diagnostic)
  • 4k bytes of screen (static) RAM
  • Self regulating power supply
  • Optional 8087 NPX co-processor

Display System

  • 25 line x 80 column screen: Characters 2 x 12 pixels in a 10 x 16 cell
  • 50 line x 132 column screen mode - software selectable
  • 12 inch (30 cm) picture tube with P39 green phospher
  • Stabilised display circuit
  • Built in 'Sunflex' optical display filter
  • Adjustable horizontal viewing angle ( ± 45° swivel)
  • Adjustable vertical viewing angle ( 0° to +11° tilt)

Disc Drives

  • Single side floppy 5¼ (130mm) Max capacity 620.544kb per side
  • Double side floppy Max capacity 121.6512kb (1.2 M byte)  
  • Single side floppy 80 tracks at 96 TPI (620544Kb)
  • Double side floppy 160 tracks at 96 TPI (1216512Kb)
  • Floppy's have 512 byte sectors: Using a GCR, 10-bit recording technique
  • Floppy disc access times:
    • 2 micro-second per bit data transfer rate
    • Interleave factor of 3
    • Average seek time approx 94 milli-seconds
    • Track-to-track step time 3ms: Latency 100ms

Keyboard

  • Seperate 8048 microprocessor
  • Software definable 7 or 10 soft function keys
  • Full IBM Selectric II (56 key) keyboard layout
  • Type ahead buffering to 32 levels and full n-key rollover
  • Capacitive keyswitches rated for 100 million operations
  • keyboard contains PCB with on-board drivers

Electrical

  • Input voltage 90-137 VAC or 190-270 VAC (Selected by internal jumper)
  • Voltage frequency 47-63 Hz
  • Output voltage regulated +5 VDC and +12 & -12 VDC
  • Output voltage un-regulated +12 VDC

  Boot up screen

 MS-Basic loaded

 Web pages:

http://en.wikipedia.org/wiki/Sirius_Systems_Technology

Info on the company: http://www.actapricot.org/home/

A users group. http://www.actsirius1.co.uk/