Mood
Loop- our new PIC-based design creates a weak electromagnetic field at "brainwave" frequencies, which may encourage mental states of relaxation, creative mental imaging and even sleep. Latest design covers an area of up to 4 metres square, inductive loop is connected by a D-plug. Variable Alpha, Beta, Delta and Theta waves, plus Schumann setting. Must not be used by epileptic persons. Source code available free from the EPE FTP site. Next month: power supply.
Build
our Handy Amp- a useful bench amplifier with built-in loudspeaker. It has low level and high level inputs and is suitable for many testing applications.
Cave
Electronics- our special feature describes ways in which electronics can assist in our exploration of the amazing sights that await us in the sub-terranean world. Lighting systems are discussed in depth and a suggested circuit for a multiple LED lamp is offered for you to experiment with. The author also outlines some of the interesting techniques in which electronics comes to the rescue, so to speak, of potholers and caving enthusiasts.
Door
Protector The first in a series of simple projects that can be built for about £10 ($16), ideal for beginners. Safe to build, many projects use standard parts for ease of construction.
Quiz
Game Indicator- a low-cost fun project for two contestants, showing clearly who pressed first. There's no arguing with our electronic project which is easy to build and ideal for beginners. The project includes both an l.e.d. indication as well as an audible tone.
Also in this issue: Circuit Surgery discusses the basic principles behind Piecewise circuit simulation; New Technology Update examines (well, discusses, anyway) atom-sized electronic devices that are currently under development; Interface describes a complete four-range resistance meter PC interface. Net Work looks at BT's latest offerings for unmetered access.