Phill's Sinclair Page

Machine Name    : Sinclair ZX80.
Processor       : Zilog Z80A at 3.5MHz.
Memory          : 1k expandable to 16k with Rampacks.
Backing Store   : Cassette 300 baud.
                  Floppy Disk, No.
                  Hard disk, No.
Firmware        : ZX integer basic.
Screen          : Text 32x22x2.
                  Graphics 64x44x2.
Other I/O       : 300 baud Cassette.
                  Expansion connector.
                  TV Modulator.
    

The Sinclair ZX80 was the first affordable home computer to be marketed in the UK. It was based around the Z80A microprocessor, together with 1K of static RAM and about twenty LS type logic chips. It came housed in a white plastic case with a membrain, touch sensitive keyboard. The basic on the ZX80 was integer only, and it also had the limitation of no string handling functions to speak of. Though Sinclair did later produce an upgrade that allowed it to be upgraded to ZX81 basic, which included full floating point maths and proper string handling.

Machine Name    : Sinclair ZX81.
Processor       : Zilog Z80A at 3.5MHz.
Memory          : 1k expandable to 64k with Rampacks.
Backing Store   : Cassette 300 baud.
                  Floppy Disk, Unknown.
                  Hard disk, No.
Firmware        : ZX basic.
Screen          : Text 32x22x2.
                  Graphics 64x44x2.
Other I/O       : 300 baud Cassette.
                  Expansion connector.
                  TV Modulator.
    

For example here's a picture of the first computer I owned a Sinclair ZX81. This machine had a touch sensitive keyboard, plugged into a T.V. and had a massive 1K of memory ! Though by the time I bought mine, I got a deal with a 16K RAM expansion.

Here's a picture of what it looked like inside !

Machine Name    : Sinclair Spectrum.
Processor       : Zilog Z80A at 3.75MHz.
Memory          : 16k, 48k. 16k expandable to 48k.
Backing Store   : Cassette 1200 baud.
                  Microdrives (100k) with Interface 1.
                  Floppy Disk, yes several up to 800k.
                  Hard disk, Roumored !
Firmware        : ZX colour basic.
Screen          : Text 32x22x16.
                  Graphics 256x192. Colour res was only 32x22x16 !
Other I/O       : 1200 baud Cassette.
                  Expansion connector.
                  TV Modulator.
    

I also have several Sinclair Spectrums.
This machine came in two versions with 16K an 48K of memory, both had the same rubber keyboard and 256x192 garphics in 16 colours. Later versions had an enhanced QL like keyboard and built in joystick interfaces.

Machine Name    : (Amstrad) Sinclair Spectrum +2, +3,
Processor       : Zilog Z80A at 3.75MHz.
Memory          : 128k.
Backing Store   : Cassette 1200 baud, built in.
                  Floppy Disk, 300k ? built in on +3.
                  Hard disk, Roumored !
Firmware        : ZX colour basic, 128k basic.
Screen          : Text 32x22x16.
                  Graphics 256x192. Colour res was only 32x22x16 !
Other I/O       : 1200 baud Cassette +3 only.
                  Mono sound output.
                  Expansion connector.
                  2xJoystick interfaces.
                  TV Modulator.
    

And one of the Amstrad manufactured Spectrum +2 machines. These where basically the same machine as the origanal Sinclair Spectrum 128, but the +2 had a built in cassette deck and Sinclair interface 2 compatible Joysticks, though Amstrad in their normal fassion changed to pinouts ! The +3 was much the same but had a built in 3" disk drive instead of a cassette deck. These machines like the Sinclair 128k machine used an inhanced sound chip that could actually play 3 voices, instead of that horrible beeper !

I also now own one of the disk based +3 machines.

Machine Name    : Sinclair QL.
Processor       : Motoraola 68008 at 8MHz (68000 compatible).
Memory          : 128k expandable to 800k, or 4Mb with Gold card.
Backing Store   : Cassette, none.
                  Microdrives, 2 x 100k.
                  Floppy Disk, optional, up to 720k. (or 3.2Mb with gold card).
                  Hard disk, Optional Sincalir 7Mb, others up to 500Mb (IDE).
Firmware        : QL SuperBASIC.
Screen          : Text 40x25x8,85x25x4.
                  Graphics 256x256x8,512x256x4. 
Other I/O       : Expansion connector.
                  2xJoystick interfaces.
                  2xRS232 Serial ports.
                  Cartrage ROM connector.
                  RGB/Composite/Sound port.
                  Microdrive expansion.
                  TV Modulator.
    

I have two QL machines, one with disks and 640K of RAM, one without ! The QL was probably the first home computer using a 32bit processor, though disadvantaged by it's 8 bit data bus. The machine had two graphics modes 320x200 in 8 colours and 640x200 in 4 colours. The machine has 128K of internal memory and two built in 'Microdrives' which store up to 100k of data on each. After market expansions have allowed the machine to bex expanded to a maximum spec of a 68020 with 4Mb of RAM and 3.2Mb floppy drives. Hard disk interfaces have also been developed to allow the machine to use the IDE type hard disks up to 520Mb.

Machine Name    : (Amstrad) Sinclair PC200.
Processor       : Intel 8086 at 8MHz.
Memory          : 512k expandable to 640k.
Backing Store   : Cassette, none.
                  Floppy Disk, Single 720k 3.5"
                  Hard disk, Optional, via standard PC interface.
Firmware        : IBM PC compatible BIOS.
Screen          : Text 40x25x16,80x25x16. (CGA) 80x25x2 (MDA).
                  Graphics 320x200x4, 640x200x2 (CGA). None (MDA).
Other I/O       : 2x8 bit IBM PC compatible expansion connectors.
                  Disk drive expansion for an external disk drive.
                  PC Analogue Joystick interface.
                  RS232 Serial port.
                  Centronics Printer Port.
                  RGB/Mono Video (CGA/MDA).
                  TV Modulator (CGA only).
    

And finally in the Sinclair section, I have an Amstrad manufactured Sinclair PC200 a PC/XT compatible machine with internal 720K floppy and 512K of RAM. I have upgraded the RAM in my machine to bring it up to the 640k maximum for an XT, replaced the Intel 8086 processor with a V30, to increase the speed. By disabling the on board graphics adapter I have fitted an EGA standard monitor (640x350x16). And also fitted a 20Mb MFM hard disk.

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