The Sinclair ZX81
One Per Desk
The Sinclair ZX81 was the first popular home computer and was the computer which launched the home computer industry - it followed on the heels of the white Sinclair ZX80 home computer (which was supplied as a kit) and came either as a kit or ready-assembled. It came complete with built in BASIC interpreter, Z80 processor and a massive 1K RAM (random access memory) and was originally sold for only £49.95 (as a kit) or £69.95 (pre-assembled), making it affordable for the mass market.
ZX81 was the first computer to adopt the Sinclair
black colour and originally came with a 700mA PSU,
which had the plug incorporated into the power supply
unit (akin to the earlier ZX80 PSU). However,
when Sinclair released its own add-on thermal ZX
printer for the Sinclair ZX80, ZX81 and Spectrum
computers, it was found that this power supply was
insufficient and the larger 1.2A PSU was released for
use with the ZX81 (this power supply unit appears
half-way along the cable). A host of add-ons
were produced both by Sinclair and other
manufacturers, including a 16K RAM pack (notorious for
crashing due to wobble). Later add-ons allowed
the use of high resolution graphics, and games in high
resolution were produced, using a software only
ZX81 continues to be dear to many people's hearts and
the past few years has seen the release of new
software (including classic games, such as Boulder
Logic and Panic), much of which uses one of several
techniques to produce hi-resolution graphics on
screen. Some software even manages to generate
sound using the original hardware, although much
better quality sound is generated using an add-on
interface with an AY-3-8910 chip.
New Sinclair ZX81 / Timex-Sinclair 1000 / Timex-Sinclair 1500 Hardware
the enthusiasm shown for the Sinclair ZX81, we are
working to release new and replacement hardware for
the humble Zeddy.
The first of
our projects was essential to help users keep their
machines alive - the production of brand new
replacement Sinclair ZX81 Keyboard Membranes, with the
integrated touch key keyboard. Since 2009 we
have sold over 700 of these membranes, reflecting the
number of people who are still ingratiated by the
little black machine
also seen the launch of the ZXpand and the ZXpand-AY Sound Module
- a brand new interface to bring the ZX81 into the
21st Century and make it a real joy to use.
The ZXpand provides the following
A Short video of the ZXpand interface
The ZXpand-AY Sound Module plugs into
the ZXpand and provides a built in Atari-style joystick
adaptor, and is complete with a full Yamaha YM2149 sound
chip (equivalent to the AY-3-8910) and an Atari style
DB-9 joystick port. The ZXpand-AY module is fully Zon-X
compatible, and uses a mixer circuit to provide stereo
Software has already been
written which allows the ZX81 to play sounds converted
using the MIDI2AY program for Windows (or even AY files
written for use with the ZX Spectrum).
A Short video of the ZXpand-AY Sound Module in
We are also investigating a range of new projects for the Sinclair ZX81 and compatibles. We welcome people to indicate which projects they would most like to see put into production. Please refer to our Sinclair ZX81 Project Page.
New Sinclair ZX81 / Timex-Sinclair 1000 / Timex-Sinclair 1500 Magazine - "MonoChrome"
We are pleased to be able to host this free magazine for ZX81 enthusiasts.
New Sinclair ZX81 / Timex-Sinclair 1000 / Timex-Sinclair 1500 Software
Due in part to the inertia behind discussions on the Sinclair ZX80 and ZX81 discussion forums, various items of software have been released for the Sinclair ZX81 over the past few years, utilising the best tools on PCs in order to create imaginative software, which is up to (or exceeeds) the standard of previous commercial releases.
We are now also beginning to see software released which makes use of the AY sound facilities provided by the ZXpand-AY and MrX Sound Interfaces, as well as the joystick port facilities provided by the ZXpand-AY, including new Sinclair ZX81 games from Revival Studios.
Other games have been adapted for to use the ZXpand's Joystick - see the thread about ZXpand Joystick compatible games on the ZX80 / ZX81 forums.
More details of the most recent ZX81 software, together with screen shots and downloads appear on our Sinclair ZX81 Software Page.
If you are interested in previous
commercial releases for the Sinclair ZX81,
then try the Sinclair ZX81
We now list all of our second hand Sinclair ZX81 items on our new SellmyRetro site - SellmyRetro.com is a site dedicated to vintage / retro electronics and computers.
<Our second hand items are in good condition (unless stated) and are all fully tested before shipping. We ensure that they are well protected against the rigours of parcel delivery and send them by Royal Mail First Class post, Parcelforce 48 hour delivery (in the UK) or other courier.
We also offer a 14 day money back warranty on all goods (excluding shipping charges), provided that they are returned in the same condition and packaging.
BASICARE ZX81 MODULE DOCUMENTATION