Sinclair QL
(Quantum Leap)
Released:January 1984
Available:May 1984
Price:399 / $570
CPU:Motorola 68008 @ 7.5MHz
RAM:128K
Display:text: 25 lines of 85 chars
256 X 256, 8 colors
512 X 256, 4 colors
Ports:2 network, 1 ROM,
2 serial, 2 video (RGB, RF),
2 controllers, system bus
Storage:2 internal 128K tape drives
OS:Qdos / SuperBASIC in ROM

Sir Clive Sinclair



Sinclair, of Great Britain, developed and sold some of the most popular home computers of the decade - the Sinclair ZX-81 and Timex/Sinclair TS-1000, each selling millions of units. They were very inexpensive, and equally limited and difficult to use.

The QL, or Quantum Leap, was designed for the business world, with a powerful CPU and advanced features.
  • The QL is one of the first system to use the new 16/32-bit microprocessors.
  • Built-in networking allows up to 64 QLs to transfer data between themselves, at up to 100K baud.
  • Qdos is the multitasking concurrent operating system, allowing simultaneous file access by multiple applications.
  • Two built-in micro-drives allow fast and convenient access to data and applications.
  • The QL comes with a word processor, a database, a spreadsheet and a business graphics package on micro-tape.
  • The SuperBASIC programming language has support for networking and advanced graphics.







  • Unfortunately, the QL was slow to market, while Sinclair was fixing hardware and software bugs. When it finally did ship in May 1984, some systems had the operating system in an external ROM, which was plugged into the back of the system.

    While the inexpensive micro-drives sounds like a good idea, they are limited in speed and data capacity. The tapes are actually tiny continuous loops of high-quality magnetic tape.
  • 200-inches of tape, running at 28 ips (inches per second), making a complete loop in about 7.5 seconds.
  • They hold a maximum of 128K of data, although 100K is more typical.
  • The micro-tapes must be removed when powering the system on or off, otherwise data-loss may occur.

  • The back of the system has plenty of connectors for networking and serial communications, as well as two controllers and two video displays. Unfortunately there's no parallel port of any kind.

     



    The boot screen asks which display device you will be using.

    <F1> will utilize the RGB monitor connector, giving the best looking display. The same connector also has composite video output, which won't be quite as nice as RGB, but better than the TV display.

    <F2> will use the RF output, in the US it will be TV channel 3 or 4 (switch selectable), in the UK, channel 36.

    SuperBASIC has an interesting multi-window appearance, but only when using a monitor for your display device. When using the TV, the entire screen is used for input, output, and user I/O.

    (This display is actually 80 characters wide, the text has been exaggerated here for your viewing pleasure)

    Upon power-up, the systems asks you whether you will be using a TV or video monitor for your display. The software display is different for each, giving a higher-resolution display for the video monitor.

    The power supply is an external brick, with 9vdc / 1.8A (generates +5vdc) and 15.6vac / 0.2A (generates +/- 12vdc) outputs.


    The micro-drives are similar to tiny 8-track tape players, with a tape head, interlock switch, and capstan.

    Transporting the tape at 28 ips is very fast, much faster than an audio tape, which is only 1-7/8 or 3-3/4 ips.


    This QL seen below, like most, has numerous upgrades and modifications inside, necessary to make it run reliably.



    Related Links

  • QL from Planet Sinclair
  • Sinclair QL review from Classic Computer Magazine Archive
  • "QL User" from "Your SPECTRUM Unofficial Archive"
  • SUMO, an unofficial archive of "Sinclair User"


  • Return to the Obsolete Technology Homepage