COMPACT HIGH-PERFORMANCE AMP Low distor tion stereo amplifier Runs from a 12V DC supply 20W into 4 :

WIN MICR A MPLA OCHIP B Sta Kit F rter o PIC3 r 2MX 1xx/2 xx

LOW-POWER CAR/BIKE USB CHARGEREfficient USB charger that can operate from a 12V car battery

SOLAR-POWERED LIGHTING CONTROLLER PART 1High efficiency solar lighting system

HIGH-QUALITY DIGITAL AUDIO SIGNAL GENERATOR PART 3How to drive the generator

t r a t S p m u J series startsNew sue this is$9.99US 4.40UKMAY 2012 PRINTED IN THE UK

PRACTICALLY SPEAKING, PIC N MIX, NET WORK, CIRCUIT SURGERY, READOUT, TECHNO TALK

PLUS

Microcontrollers

Microchip Development Tools Take Cost and Time Out of Embedded DesignSupported by Industry-Leading MPLAB Single Development Environment

Digital Signal ControllersAnalog

MemoryRF & Wireless

With over 1.15 million development systems already shipped, Microchip Technology has a reputation for providing a comprehensive range of world-class, low-cost, easy-to-use application development tools. Combining Microchips powerful free MPLAB IDE with application- and product-specific starter kits cuts the cost and complexity of your embedded designs. MPLAB X IDE is the new single, universal graphical user interface for Microchip and third party software and hardware development tools. It is the industrys only IDE to support an entire portfolio of 800+ 8-bit, 16-bit and 32-bit PIC MCUs, dsPIC DSCs and memory devices. It includes a feature-rich editor, source-level debugger, project manager, software simulator, and supports Microchips popular hardware tools, such as the MPLAB ICD 3 in-circuit debugger, PICkit 3 starter kit, and MPLAB REAL ICETM in-circuit emulator. Based on the open-source NetBeans platform, MPLAB X runs on Windows OS, MAC OS and Linux, supports many third-party tools, and is compatible with many NetBeans plug-ins. Add starter kits, reference designs and webinars for specific PIC MCU and dsPIC DSC families and you have all the tools you need to fast-track your embedded design. The low-cost starter kits help you to use application-optimised PIC MCU and dsPIC DSC families in wireless and wired networks, security, motor control, automotive and low-power designs, as well as in graphics and general-purpose applications.

THE MPLAB IDE TOOLKIT FOR FAST AND EFFECTIVE EMBEDDED DESIGN:

MPLAB ICD 3 - DV164035

MPLAB REAL ICE - DV244005

PICkit 3 Debug Express - DV164131

Start now! Download the MPLAB IDE Quick Start manual at: www.microchip.com/toolswww.microchip.com/toolsThe Microchip name and logo, the Microchip logo, dsPIC, MPLAB and PIC are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. PICkit, PICDEM and REAL ICE are trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. All other trademarks mentioned herein are property of their respective companies. 2011, Microchip Technology Incorporated. All Rights Reserved. DS52032A. ME297AEng/10.11

ISSN 0262 3617z PROJECTS z THEORY z z NEWS z COMMENT z z POPULAR FEATURES zVOL. 41. No 5 May 2012

INCORPORATING ELECTRONICS TODAY INTERNATIONAL

www.epemag.com

Projects and CircuitsCOMPACT HIGH-PERFORMANCE 12V STEREO AMPLIFIER by Nicholas Vinen Have you been looking for a 12V, low distortion amp this is the one for you! HIGH-QUALITY DIGITAL AUDIO SIGNAL GENERATOR PART 3 by Nicholas Vinen The driving instructions for this sophisticated signal generator project LOW-POWER CAR/BIKE USB CHARGER by Nicholas Vinen Achieve up to 89% efficiency with our USB charger operating from a 12V car battery 10 24

30

SOLAR-POWERED LIGHTING CONTROLLER 38 PART 1 by John Clarke Build a high efficiency solar lighting system with MPPT and three-stage charging

Series and FeaturesTECHNO TALK by Mark Nelson Statistics JUMP START by Mike and Richard Tooley Electronics for newcomers Moisture Detector CIRCUIT SURGERY by Ian Bell Triac driving PRACTICALLY SPEAKING by Robert Penfold Front panel design PIC N MIX by Mike Hibbett chipKIT Arduino development Part 2: Altitude Indicator NET WORK by Alan Winstanley On guard!... Whats next?... Lifes a lottery... On location 22 48 58 61 64 74

Regulars and ServicesEDITORIAL Updates to recent items: Raspberry Pi... Jump Start... EHT Probe NEWS Barry Fox highlights technologys leading edge Plus everyday news from the world of electronics 7 8 29 56 68 71 76 78 79 80

Jump Start

MICROCHIP READER OFFER EPE Exclusive Win a Microchip MPLAB Starter Kit For PIC32MX1xx/2xx SUBSCRIBE TO EPE and save money CD-ROMS FOR ELECTRONICS A wide range of CD-ROMs for hobbyists, students and engineers READOUT Matt Pulzer addresses general points arising DIRECT BOOK SERVICE A wide range of technical books available by mail order, plus more CD-ROMs

EPE PCB SERVICE PCBs for EPE projects Wimborne Publishing Ltd 2012. 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. ADVERTISERS INDEX NEXT MONTH! Highlights of next months EPE

Our June 2012 issue will be published on Thursday 3 May 2012, see page 80 for details.

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