Computers can, as science fiction and advertising suggest, be used, when interfaced correctly, to control an endless variety of physical devices. All too often their full potential is not realised. Ignorance or myths about the complexities of such implementations prevent most capable users from venturing into this area of application. 20 Simple Electronics Projects For The ZX81 And Spectrum by Stephen Adams should put an end to any apprehension. The contents of the 100 or so pages instruct on the construction of a burglar alarm, a light pen and an analogue digital converter and a further 17 projects; he theory and techniques learned will provide for countless more.

Each topic is accompanied by full descriptive text, clear and logical illustrations and background notes where necessary. Stephen Adams' treatment of the subjects should make them both comprehensible and appealing to anyone who has sat through a couple of years of school physics.

Now in its second edition, 20 Simple Electronics Projects For The ZX81 And Spectrum was a success the first time around and it may well be for you. Published by Interface Publications.