Everyday practical electronics 2009 08

Everyday practical electronics 2009 08

RECYCLE IT

A low-cost large-display anemometer from recycled parts

BREADBOARDING PROJECTS

ROLLING CODE KEYLESS ENTRY SYSTEM

FAST CHARGER FOR NiMH BATTERIES

A versatile, safe charger to suit any size cells

$8.75 US $10.25 CAN

AUGUST 2009 PRINTED IN THE UK

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Everyday Practical Electronics, August 2009 1

Projects and Circuits

ROLLING CODE KEYLESS ENTRY SYSTEM – PART 1 by John Clarke 10

Rolling code makes it super secure Can respond to up to 16 keyfob transmitters

SIMPLE DATA-LOGGING WEATHER STATION – PART 2 by Glenn Pure 24

Records rainfall and temperature, and operates completely unattended

FAST CHARGER FOR NiMH BATTERIES by John Clarke 36

Can charge up to 15 identical NiMH or NiCad cells

BREADBOARDING PROJECTS by Dr Malcolm Plant 56

Part 11 – Festive Lights

Optical Motion Detector

Series and Features

TECHNO TALK by Mark Nelson 22

Diatomic power

A low-cost large-display anemometer

Calculated connection

CIRCUIT SURGERY by Ian Bell 64

Filter circuits – Part 2

PIC N’ MIX by Mike Hibbett 68

PIC RS232 terminal

The more things change; A plateful of spam

Regulars and Services

EDITORIAL 7 NEWS – Barry Fox highlights technology’s leading edge 8

Plus everyday news from the world of electronics

New book with Free CD-ROM – Using PIC Microcontrollers

BACK ISSUES Did you miss these? 34

A plethora of handPICed projects

EPE PIC Tutorial V2, plus PIC Toolkit Mk3 and a selection of PIC-related articles

SUBSCRIBE TO EPE and save money 55

The Modern Electronics Manual and Electronic Service Manual on CD-ROM

A wide range of CD-ROMs for hobbyists, students and engineers

READOUT Matt Pulzer addresses general points arising 73

A wide range of technical books available by mail order, plus more CD-ROMs

© Wimborne Publishing Ltd 2009 Copyright in all

drawings, photographs and articles published in

EVERYDAY PRACTICAL ELECTRONICS is fully

protected, and reproduction or imitations in whole or

in part are expressly forbidden.

Our September 2009 issue will be published on

Thursday 13 August 2009, see page 80 for details.

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N... 1N5400 £0 .08 1N5402 £0 .08 1N5406 £0.10 1N5 408 £0.10 6A1 £0.30 6A4 £0.28 6A8 £0.30 BA157 £0.07 BAT41 £0.12 BAT46 £0.12 BAV21 £0.07 BAX16 £0.05 BY133 £0.10 OA200 £0.56 UF4002 £0 .08 UF4004 £0 .08 UF4006