A Quick History...
The Sinclair QL (QL standing for Quantum Leap), was launched on the 12th January 1984 at a very high profile event in London, carefully timed about two weeks before the launch of the Apple MAC!
Sinclair himself did not like the fact his Spectrum computer was largely seen as a games machine and he wanted to compete in the lucrative business computer market.
Although being considerably cheaper than it's competitors, a rushed development led to launch delays, unfinished operating system, bug-ridden BASIC interpreter, partly finished software supplied with the machine.
Once finally launched, the problems continued with poor reliability, and initially a whole run of machines that did not work as advertised.
Adding to this, the use of Sinclair's microdrive tape cartridges instead of the floppy disk drives (that most would have preferred at the time for a home and business computer), went a long way to killing off the computer's chances of success before it had really got started.
However, the main problem facing the QL if it was to be taken seriously as a potential business machine, was it's choice of storage and media.
Two built-in Microdrive tape-loop (stringy-floppy) cartridge drives provided mass storage, in place of the more expensive floppy disk drives found on similar systems of the era, which were the first choice for business computers. The microdrive hadn't worked well in its first incarnation as a storage peripheral for the Spectrum so it's inclusion on the QL was not exactly a welcome one.
The microdrives and cartridges were much cheaper than disk drives, and their size helped to keep the down the footprint of the QL to to conserve desk space. However, the drives themselves were less than reliable.
The tapes if used with the same QL would work well enough, but if inserted into another machine would often not read or become damaged, as consistency of calibration between drives was poor.
Based on a Motorola 68008 processor clocked at 7.5 MHz, the QL included 128 KB of RAM (officially expandable to 640 KB) and could be connected to a monitor or TV for display.
Interfaces included an expansion slot, ROM cartridge socket, dual RS-232 ports, proprietary QLAN local area network ports, dual joystick ports and an external Microdrive bus. Two video modes were available, 256×256 pixels with 8 RGB colours and per-pixel flashing, or 512×256 pixels with four colours (black, red, green and white). Both screen modes used a 32 KB framebuffer in main memory.
The case was another classic design by Rick Dickinson externally, and is still sought after with plenty of after market products to lessen it's short comings such as an internal SD interface for instat storage and loading of software,
The QL was instantly removed from market as soon as the takeover deal with Amstrad was completed and that was the end...