Projects in the November 2002 issue of EPE Magazine

PICAXE Projects (Part 1) - Egg Timer, Dice Machine, Quiz Game monitor. PICaxe is a great way to introduce yourself to the world of PIC microcontrollers. We use modified PIC16F627 devices that can be programmed in BASIC. They do not need special programming hardware and they can be programmed through a PC serial link. Using the PICaxe system, you do not need specialist equipment or knowledge to program the PIC microcontrollers used in these designs. The flexibility of PIC microcontrollers is considerable and this series of articles is based around a variant of one of them, using a general purpose circuit and PCB allowing nine different projects to be realised.

Transient Checker - solve a pesky problem caused by "spikes" or mains transients with our Transient Tracker. Easy to build, this device can be preset to respond with a beep when spike voltages above a certain threshold are detected. 230V or 115V a.c.operation. Transformerless PSU design, for the more experienced constructor.

In December 2002 issue (P. 863) we advised that, contrary to information supplied, Class Y capacitors are intended for use between mains and earth, and not directly across the mains supply. Class X types are designed for continuous use across mains and neutral.
EPE Hybrid Computer (Part 1) — Real-time computation of complex system behaviour is greatly simplified by combining analogue and digital processing techniques -- and that's exactly what we've done in this new Analogue Computer design. It has features too numerous to list here, and includes:
  • 10 analogue amplifiers
  • Each can act as an Adder or Integrator
  • Eight co-efficient multipliers
  • Three modes of operation, Compute, Hold and Reset
  • Automatic or Manual control mode.
  • ATOM microcontroller
  • Programmable in BASIC
  • PCB carries all major components
  • PC interface.

Full step-by-step details are provided in our two-part series, along with free programs to demonstrate its effectiveness.
Tuning Fork & Metronome — thrill everyone by (at long last) getting your musical instrument properly tuned! This PIC-powered project generates the initial seven natural notes of any octave. It also compares its own tone against the frequency of an acoustic or electrical input, via its built in microphone or line input. Indication via an l.e.d. Also has a built-in metronome feature with accentuated downbeat.

Also in this issue: New Technology Update: how optical illumination of crystals and nano-tubes reveals their data storage potential; Net Work looks at effective anti-spam email filtering systems; Ingenuity Unlimited offers more readers' own circuits.