Projects in the June 2004 issue of EPE Magazine

'Quickstep' stepper motor driver - this simple and versatile stepper motor driver and controller is ideal for testing or using four phase unipolar types of stepper. Uses a PIC 16F628, with source code available free from our download area. A four-key push button pad allows for single or continuous step, forward or reverse. The output drivers are 2 amp discrete transistors that will cope with many types of new or surplus steppers. Battery power-saving feature.

Crafty Cooling - make a drinks can cooler, and learn about the Peltier and Seebeck effects at the same time! This article explains the theory behind solid-state electronic coolers (of the sort used in e.g. battery-operated in-car drinks coolers), and you have a chance to build your own experimental fan-assisted chiller using the principles explained. You can also adapt the techniques for use in your own projects.

Midi Synchronome - Now you can improve your musical timekeeping when recording MIDI instruments, using this novel audio-visual electronic aid. The MIDI Synchronome will automatically synchronise to the clock messages output by most MIDI instruments or computer sequencers. Furthermore, it also simulates the swinging arm of a traditional metronome with nine l.e.d.s. The circuit is based on a PIC 16F627, with free source code available from our download area. Simple stripboard design.

Body Detector Mk. 2 - Create your own invisible defence shield with this updated version of the original Body Detector. Not much bigger than a matchbox, the circuit uses a super-sensitive detector and amplifier to respond to the capacitance of the human body. It is extremely sensitive and can be used to protect objects in burglar-alarm mode or in a number of other adaptations.

For example, the detector wire can be hooked to a metal doorknob, or even an outdoor item such as a motorcycle, and extra options for ground/ earth wires can boost the circuit's sensitivity even more. The circuit has a multitude of uses limited only by your imagination (and desire to experiment!).

Teach-In 2004, Part 8 - our flagship educational series is specially written for those new to electronics or who wish to brush up on their knowledge. In this month's issue, the subject of movement detection is discussed along with 'missing pulse' detection techniques. A variety of astable oscillators are shown, including some interesting examples of 555 application that can be built easily on solderless breadboard.

Interface - the column for computer enthusiasts. This month we have more practical ideas for the case-modding enthusiast. How to add an electroluminescent (EL) panel, and several control circuits for flashing, dimming or sound-to-light modulating EL drivers, to give your PC a bit more life!

ALSO IN THE JUNE 2004 ISSUE: Clinical electrotherapy developments through the ages, and a look at future trends, including deep-brain stimulation using the Kinetra implantable pulse generator. Circuit Surgery: power op.amps, servo controllers and more. Ingenuity Unlimited - more readers' own circuits. Techno Talk on time-limited self destructing electronics. PIC n MIX our new series for 'PICinners' gives you a potted history of the EPE Toolkit and an overview of other low-cost PIC programmers. ALL THIS AND MORE IN THE NUMBER ONE HOBBY AND EDUCATIONAL ELECTRONICS MAGAZINE - SUBSCRIBE NOW!