Everyday Practical Electronics, September 2011

WIN MICR A OCH IP Start er Ki t For A ndro id

HIGH QUALITY STEREO DAC ‡ Accepts both optical and coaxial inputs ‡ Lets you use your DVD player to play CDs properly ‡ Eliminate poor sound quality, buzz and hum problems

OLD CASSETTE DECK + WOOD + VCR PARTS = LAND SPEED RECORD TOY CAR Another five fun uses for salvaged parts

DIGITAL MEGOHM AND LEAKAGE CURRENT METER An electronic megohm and leakage current meter, for quick and easy testing of insulation in wiring

PLUS

TEACH-IN 2011 – PART 11 Summing up!

$8.99US

£4.25UK

SEPT 2011 PRINTED IN THE UK

Microcontrollers

World’s Lowest Power Microcontrollers with USB OTG

Digital Signal Controllers Analog Memory

t Combine eXtreme Low Power with Full-Speed USB device, embedded host, dual role and On-The-Go

GET STARTED IN 3 EASY STEPS 1. Purchase a USB Starter Kit 2. Download Free USB Software 3. Order Free Samples www.microchip.com/usb

t Widely available through worldwide distribution channels t Download FREE USB stacks and drivers including thumb drive support - Host, OTG and Device Stacks - Class Drivers (HID, Mass Storage, CDC Drivers) - Thumb Drive Support (Mass Storage Driver, SCSI Interface, File Management)

Family

Flash Program Memory (KB)

Pins

USB Type

Microchip USB Starter Kit

Sleep Current Sleep with Watchdog Sleep with Real (nA) Timer (nA) Time Clock (nA)

PIC18F14K50

8-16

20

Device

24

450

790

PIC18F46J50

16-64

28-44

Device

13

813

813

PIC24FJ64GB004

32-64

28-44

OTG, Dual Role, Embedded Host, Device

20

220

520

www.microchip.com/usb The Microchip name and logo, the Microchip logo and PIC are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. All other trademarks mentioned herein are property of their respective companies. © 2010-2011, Microchip Technology Incorporated. All Rights Reserved. ME250CEng/05.11

RF & Wireless

Extend the battery life in your portable USB application using PIC® microcontrollers with integrated USB and XLP technology. Get the world’s lowest power USB microcontrollers with the flexibility to communicate as an embedded host or device.

ISSN 0262 3617 z PROJECTS z THEORY z z NEWS z COMMENT z z POPULAR FEATURES z VOL. 40. No 9

September 2011

INCORPORATING ELECTRONICS TODAY INTERNATIONAL

www.epemag.com

Projects and Circuits BUILD A HIGH-QUALITY STEREO DAC FOR SUPERB SOUND FROM YOUR DVD PLAYER – PART 1 By Nicholas Vinen Versatile design accepts both optical and coaxial inputs DIGITAL MEGOHM AND LEAKAGE CURRENT METER by Jim Rowe An electronic megohm and leakage current meter, for easy testing of insulation DELUXE 3-CHANNEL UHF ROLLING CODE REMOTE CONTROL – PART 2 by John Clarke Putting it all together and getting the two parts talking to each other – securely!

10 22

32

AUTO-DIM ADD-ON FOR THE 6-DIGIT GPS CLOCK by Jim Rowe A low-cost add-on for the Digital GPS Time Display published in May/June 2011

39

INGENUITY UNLIMITED Low-Battery Indicator – Go/No-go

68

Series and Features TECHNO TALK by Mark Nelson Edible computing

38

RECYCLE IT! by Julian Edgar Six fun projects from salavaged parts

43

TEACH-IN 2011 by Mike and Richard Tooley Part 11: Summing it all up

46

CIRCUIT SURGERY by Ian Bell Attending to noise and stability

58

MAX’S COOL BEANS by Max The Magnificent Acting mentor... Endless patience... Any ideas?

62

PRACTICALLY SPEAKING by Robert Penfold Sourcing components

64

NET WORK by Alan Winstanley Quick off the mark... Keep taking the tablets… Chrome-plated

72

Regulars and Services EDITORIAL Ingenuity Unlimited – Pico prize winners

7

NEWS – Barry Fox highlights technology’s leading edge Plus everyday news from the world of electronics

8

MICROCHIP READER OFFER 42 EPE Exclusive – Win a Microchip Accessory Development Starter Kit For Android EPE BACK ISSUES Did you miss these?

57

SUBSCRIBE TO EPE and save money

63

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

69

PIC RESOURCES CD-ROM 74 EPE PIC Tutorial V2, plus PIC Toolkit Mk3 and a selection of PIC-related articles © Wimborne Publishing Ltd 2011. 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 October 2011 issue will be published on Thursday 8 September 2011, see page 80 for details.

Everyday Practical Electronics, September 2011

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

75

EPE PCB SERVICE PCBs for EPE projects

78

ADVERTISERS INDEX

79

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