Projects in the June 2003 issue of EPE Magazine

PICRONOS (Part 1) - A giant-size 250mm diameter LED clock with a difference - it uses an inner ring of 60 l.e.d.s displaying both seconds and minutes, an outer ring of 12 l.e.d.s displaying hours, plus an inner zone of 100 l.e.d.s in 7-segment style, giving time, month, days and temperature. PIC 16F877 based design, mains-adaptor powered, battery backup. Free PICmicro source code available from our FTP download site. Large p.c.b. aids construction.

In July 2003 issue (p. 503) we said that Fig. 5, IC5 pins 1 and 9 should be
connected to the +5V line,not 0V. The p.c.b. is correct.

EPE PIC Tutorial Version 2 (Part 3). The final part of our free PICmicro tutorial series, simply the easiest low-cost way to learn about these devices. Also includes a brief look at some advanced concepts and two other PICmicro families. If you want to get to grips with PIC micros, this is the series for you! Back issues are available from our Online Shop.

Practical Radio Circuits - Part 1. The start of a brand new series introducing the principles of radio. The series features a variety of practical circuits for the set builder and experimenter. In Part One we offer an introduction to radio waves, and suggest three projects for you to build: a simple crystal set, a single i.c. radio receiver based on the MK484 (was, ZN414), and a headphone amplifier.

This practical series is specially written to dispel the mysteries of radio and will be of interest to novices and experienced constructors everywhere.

Back to Basics (Part 5) - Mini Theremin - our Back-to-Basics transistor series concludes with a simple Theremin design, a mini musical instrument that is played by placing a hand near to an aerial/ antenna plate.

Back to Basics (Part 5) - Twilight Switch -switches on a low power lamp at dusk and off again at dawn. Many uses as an automatic light-sensitive switch. Optional triac or relay output for controlling a mains load.

"FIDO" Pedometer. A novel design that keeps track of how far you have walked! PIC 16F84 design, works in miles or kilometres. Reasonable accuracy of distance is provided by detecting and counting the number of strides. It can record the distance traversed and also calculate average speed. The unit isworn around the left upper calf, and two mercury switches detect correct leg motion.

Also in this issue: Ingenuity Unlimited (readers' own circuit ideas) - Techno Talk - powerline communications, a boon or bogey? Circuit Surgery - more on how to read circuit diagrams. New Technology Update - adding silicon to Li-Ion batteries improves performance. Interface for PC users - MSCOMM voltage levels and batch counting.