EDO MULE VAN a AUG Ug PRIGI TESTED UIE a LOTS PLR p= VERYDAY PRACTICAL ‘meet ELEC. TRONICS COAT OU eee LIGHTNING DETECTOR DIGITAL SPIRIT LEVEL « Works with 14-bit, three-axis MEMS accelerometer e PIC control uses sophisticated digital algae processing e Accurate to 0.1° over, 3607 Be ¢ Four-digit LED display~ INTERPLAN ETARY/ VOIGE ‘EXTERMINATE!’ NEVER SOUNDED, Bo GOOD yey COMPLETE Ma TSU DESCRIPTION OF THE ULTIMATE\SILICON.CHECKER Raspberry Pi allem ais Maul are Jump Start DE (Contnol let forOne platform for 8-, 16- and 32-bit development - with Microchip’s MPLAB® X IDE Co Oe “4 en AYE a Te War cE 16-bit PIC® Microcontrollers & Ce Come ere EST a Controllers Page oes eC aa ae Dee | Pere | Poni Prey iN Coe Core toe Cues tis MPLAB® X IDEis the free, integrated toolset forall of Microchip's 900+ 8., 16- and 32-bit PIC? Microcontrollers, dsPIC* Digital Signal Controllers, and memory devices. 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. also cutting code size by 35%, These new compilers give < designers the choice of Fee, Standard or ro code optimisation levels for8-bit, 16-or 32-bit development, or a single C compiler suite to support all Microchip Microcontrollers and digital signal controllers. Microchip's tool chain of compatible compilers e and debugger/programmers operate MPLAB XC compilers help increase code speed of any PIC Microcontroller or dsPIC* digital signal controller by 30%, whilst seamlessly within the universal, cross platform and open-source MPLAB*X integrated. development environment, reducing both learning curves and tool investments. ES rg 512K Flash BRA rd Download a free copy of MPLAB X and choose from a choice of new C compilers MPLAB XC8 for 8-bit MCUS MPLAB XC16 for 16-bit MCUs and DSCs MPLAB XC32 for 32-bit MCUs MPLAB XC Suite for all 900+ PIC MCUs and dsPIC DSCs. Evaluate MPLAB X today! www.microchip.com/get/eumplabx eee MicrocHiP Microcontrollers * Digital Signal Controllers * Analog * Memory * WirelessISSN 0262 3617 © PROJECTS © THEORY © OO ee Load © POPULAR FEATURES © PCa Oe) CEOe TE} f EVERYDAY PRACTICAL ELECTRONICS INCORPORATING ELECTRONICS TODAY INTERNATIONAL www.epemag.com Projects and Circuits LIGHTNING DETECTOR by dohn Clarke Work and play safely inthe o SEMTEST - PART 2 by Jim Rowe Introducing the ful cuit ofthis versati DIGITAL SPIRIT LEVEL, By Anew Lew with our atmosphere megavok dodger! discrete component chocker 10 18 fan end to wonky shelves, but a great introduction to MEMS components INTERPLANETARY VOIOE 38. by John Clarke Extominatel ~ tho ultimate Dalek and Darth Vader voice pr INGENUITY UNLIMITED oo Electric blanket controler - Turvup the heat! ‘TECHNO TALK by Mark Noison ar Not what you expected? MAX'S COOL BEANS by Max The Magnificent 46 Grains of sand.. Wioless mesh networked pro rio hats, What are the chances..? JUMP START by Miko and Richard Tooley a Dc Motor Controler RASPBERRY PI_by Mike Hibbett 54 Further investigation PIC NY MIX by Mike Hivbett 87 reasing the speed - saving power CIRCUIT SURGERY by lan Boll 60 Fip-fop architecture PRACTICALLY SPEAKING by Robert Penfold 6s Project x! NET WORK by Alan Winstanley 2 Pocket the Best. Far sited. Herding cats EDITORIAL 7 Lightning, Daleks and acceleromet MEWS — Barry Fox highlights tochnology's leading edge 8 Plus everyday news from the werid of electronics MICROCHIP READER OFFER "7 EPE Exclusive - Win a Microchip XLP it Development Board ‘SUBSCRIBE TO EPE and save money 26 EPE BACK ISSUES Did you miss these? 56 CD-ROMS FOR ELECTRONICS 70 [wide range of CD-ROMs for hobbyists, students and engineers DIRECT BOOK SERVICE 5 ide range of technical books avalable by mailorder, plus more CD-ROMs gonece vexvoon 738 PCBs for EPE projects {© Wimborne Publishing Ltd 2013. Copyrightin al ‘rawings, photographs and aries pubishod in ROMER TieaEs Ee y "oe EVEMDAY PRACTICAL ELECTRONICS italy NEXT MONTH! - Highlights of next month's EPE 20 Drotected, and reproduction or imitations in whole or In part are expressly torsion (ur Ape 2013 issue wil be published on Readers’ Services - Editorial and Advertisoment Departments 7 Thursday 7 Maren 2013, ee page 80 fr deta Everyday Practical Electronics, March 2013QUASAR ee aed YY Ena ice mers rtey Perr NON anys TES) eee orn 'USB/Seral connection. Header cable for ICSP. Free Windows XP sof ware, See website for PICs Supported. ZIF Socket and JUSE lead extra, 18Vde Kit Order Code: 3149EKT - £49.95 ‘Assembled Order Code: ASS149E - £64.95 ‘Assembled with ZIF socket Order Code: ASSSEZIF - £7495 USB PIC programmer for a wide range of Flash devices—seo \wobste for details. Froe Windows, Software. ZF Socket and USB lead not included. Powered via USB port = no external power supply required, Assembled with ZIF socket Order Code: ASUTSOZIF = £6495 Uses serial port and any Standard tana comms program. 4 LED's display the status. ZIF sockets not incuded. Supply: 16Véc kit Order Code: 3123KT - £28.98 ‘Assembled Order Code: ASS123 - £29.95 Go from complete beginner to buming @ PIC and writing Code in no time! Includes 49 page stop-by-stop POF Tutorial Manual, Program ming Hardware (wth LED teat section), Win 3.11—XP Programming Software (Program, Read, Very & Erase), ‘and ‘rewtable PICTGFEAA that you can use with cifferent code (4 detalod examples pro ‘ide for you lo learn from). PC paralel port Kit Order Code: 3081KT £16.95 ‘Assembled Order Code: AS3081 -€24.95 Low cost PIC program- ‘mer board supporting ‘wide range of Micro chip® PIC™ microcon- twolers, Requires PC serial port. Windows Interface suppted Kit Order Code: KBO76KT - £34.95 01279 ore ard The PIC Programmer & Experimenter Board with test buttons and LED ind cators to carryout educa. sional experiments, such as the suppliod programming examples. In ‘cludes a 16F627 Flash Microcontrolier that ean be reprogrammed upto 1000 times for fexpecimenting at wll Sofware to compile ‘and program your source code is included, Kit Order Code KEO4EKT - £34.95 ‘Assembled Order Cod: VMI11 - £44.05 eee a Reed eiere 5 digital nput chan- nals and 8 digital out put channels plus two ‘analogue inputs and two analogue outputs ‘with & bit resolution, 16 Order Code: KBOSSNKT - £29.95 ‘Assembled Order Code: VMI1ON - £43.95 i State-of-the-Art. High secunty 4 channels. Momentary or latching relay output. Range up tom. Up to 15 Tx can be learnt by one Rx (kit in cludes one Tx but more avai able soparatsiy) 4 indicator LED's, Ric PCB. T7xB5mm, 12Vdc18MA (standby). Two & Ten Channel versions also aval Kit Order Code: 3180KT - £84.95, ‘Assembled Order Code: AS3180 - £64.95 ‘Sena port 4-channel tom: perature logger. °C or Continuously ogs up to 4 separate sensors located 200m from boars. Wide {Bhg0 of roe software applications for stor- inglusing data. PCB just 45x45mm. Poworod by PC. Includes one DS1820 sensor. Kit Order Code: S145KT - £19.95, ‘Assembled Order Code: AS3145 - £26.95 ‘Adelional DS 1820 Sensors - £4.98 each Pace next to a mabile phone (not included), Allows toggle orauto- | timer contol of 3A mains rated ‘output relay from any location ‘wth GSM coverage, Kt Order Cose: MK 160K £11.95 oo 46779 Cal your phone ru ber sing OTM prone fem anywhere inthe wot and re moa trn ono any atthe sroigysasce. @ Shed User stale Securty Password, Ant Tamper Rings to Anewer Ato Hangin and Uso Ince plate case. 130 110% Semm, Power: fave Ket Order Code: 240K - £79.95 ‘somblod Order Coae: ASST40- £9495 Computer controled 8 channel relay board, 5A maine raled relay outputs ‘and 4 optoisoated digital inputs (lor monitoring wich states, etc), Useful ina variety of control and sonsing applications, Programmed via serial port (use our new Windows interface, termi- fal emulator or batch files). Serial cable can be up to 35m long. Includes plastic case 130x100xa0mm, Power. 12V/de/500mA. kit Order Code: S108KT - £74.95 Assembled Order Code: AS3108 - £80.95 s onto 12 onboard ays wth Coe, iisitcroceie con trol unt. Topi or momentary ‘Smt range, 112 122mm. Supply. 2v8005h Ket Onder Code: OKT £6495 Assembled Order Code: ASD - £74.95 Detect OTM tones from tape recorders, receivers, two-way radios, te using the bullin mic or direct from the phone line. Char. acters ae displayed on a 16 character dleplay a8 they are received and up to 32 numbers can be displayed by scr ing the display. Al dala wettan tothe LCD is aso sent o serial output for conection to a ‘computer. Supply. §-12V DC (Order Code SU303). Main PCB: 55x95em. Kit Order Code: 3159KT - £37.95 ‘Assembled Order Code: ASS153 - £49.95 3 independent high power ‘channels. reprogrammed ‘or user-editable ight se ‘quences. Standalone op- tion and 2-wire sera ine face for microcontroler ot PC communication with simple command set Suitable for common anode RGB LED stips, LEDs ang incandescent bulbs. 56 x 39 x 20mm. 12A total max. Supply: 12Vse iit Order Code: 8191KT £29.95 ‘Assembled Order Code: ASB1S1 - £99.95Desa edger eae 4 channel computer serial poe temperature monitor an roy con. troller with four inputs {or Dallas 0518820 or 10518820 aigtal thor ‘mometer sensors (£3.95 each). Four 5A {ated relay channels provide output contre Rolays aro independent of sensor channel, allowing flexibly to setup the nage in any way you choose, Commands for reaging temperature and relay control sent va the 5232 interface using imple text stings. Control using a simple terminal / corns program (Windows HyperTerminal) or our free Windows application softwar, Kit Order Code: 3190KT - £84.95 ‘Assembled Order Code: AS3190 - £99.05 Feature packed non-volatile 40 second multemessage sound recorder module ts ing a high quality Winbond sound recorderic. Stand- I alone operation using just six onboard but: tong or use onboard SPI interface. Record using builtin microphone of external ine in, 8:24 Vde operation. Just change one re Sisto for diffrent recording Guraion!sound quality. sampling frequency 4-12 kHz Kit Order Code: 31887 - £29.95 ‘Assombled Ordor Code: AS3188 - £97.95 120 second version also avaiable Got better performance from your stepper motors with this dial full bridge motor driver based on SGS Thompson chips L207 & (298. Motor rent foreach phase set Using on-board potentiometer. Rated to han- dia motor winding currents up to2 Amps per phase. Operates on 9-36Vde supply voltage. Provides al basic motor contols including full Or hal stepping of bipolar steppers and cr tion conta. Allows multiple iver synchron sation, Perfect for desktop CNC applications Kit Ordor Cod: 3187KT - £39.95 Assembled Order Code: ASS187 -£49,95 Digitally cleans the video signal and removes un- wantod distortion in video Saal natn ties quality and luminance Muctsations, You wil aio benef fom improved picture ‘On LCD monitors or projectors. (Code: KEO30KT £29.95 Ascombled Order Code: VMI06 - £44.95 Les ey Control the speed of ‘almost any commen OC ‘ator rated up to $0OVI7 SA, Pulse wicth ‘modulation output for ‘attimum motor tongue at all speeds. Supply: 5-15Vde. Box supplied. Dimensions (mm): 6OWx100Lx60H, Kit Order Code: 3067KT - £19.95 Assembled Order Code: AS3067 - £27.95 Control the spoed of ‘mat commen OC rotors (rated up to '32Vde/10A) in both the forward and reverse roction, Tha range of conto rom fuly OFF to fully ON in both ioctions. The direction and speed are con- trolled using a single potentiometer. Serow terminal block for connections Kit Order Code: $166v2KT - £23.95 Assembled Order Code: AS3166v2 - £33.98 E Drives any 5-35Vde 5, 6 or Bead unipolar slepper ‘motor rated up to 6 Amps. Provides speed and direc: tion control. Operates in stand-alone or PC- contlled mode for CNC use, Connect up to ‘3179 driver boards toa single parallel Port Board supply: 9Vde. PCB: 80x50mm, Kit Order Code: 3170KT £17.95 Assembled Order Code: AS3179 - £24.95 Drive any §-50Vde, 5 Amp Dipolar stepper motor using extorally suppiod SV lev ts for STEP and DIREC. TION control. Opto-solated Inputs make it ideal for CNC applcatons Using a PC running sutabo sofware, Board supply: 8-30Vde. PCB: 75x85mm. Kit Order Code: 3158KT - £26.95 Assembled Order Code: AS3158 - £34.95 Rolable and simple to Install project that allows you to adust the speed of an electric dior 230V AC Single phase induction rotor rated up to 600, ‘Watts. Simply tum the potentiometer to adjust the motore RPM. PCB: 48x05mm, Not su able for use with brushiess AC motos Kit Order Code: 1074KT -£15.95 ‘Assembled Order Code: AS1074 - £23.95 @ QUASAR 5 eo or pce sci Peas eager Top o the range. Com plete selcontained elec: tronics couree. Takes you from beginner to A Level standard and beyond! Contains all the hardware and manuals to assemble 500 projects. You got 3 comprehensive course books (total 388 pages) - Hardware Ey Course, Hardware Advanced Course and a microprocessor based Software Prograrn ‘ming Course. Each book has individual crcult explanations, schematic and connaction da ‘grams. Suitable forage 12+ Grder Code EPLS00- £179.95 ems rag Features 2 input chan- nels ~ high contrast LED ‘eth white back -fll auto setup for valvay ‘and taldv «recorder roll mode, up to 170h per screen -tngger mode: run normal - once - rol adjustable tig {ger level and slope and much more Order Code: APS230 - £40085 6304.9 The Personal Scope is not a graphical multimeter But a com Biote portable oscllascope at the Sze and the cost of a good mul timeter. Its high sensitivity - down to 0.tmVidlv= and extended scope functions make this unit ideal for hobby, srvice, automo: tive and development purposes. Because of is exceptional value for money. the Personal Scope is wol suited for educational use Order Code: HPS10 - C3895Everyday Practical Electronics march 2023 Featured Kits Theremin Synthesiser Kit MkII USB Power Monitor Kit Kossiser1.00 kessi7et00 kes2e6 624.75 Garbage and Recycling we-7502 £6.78 Reminder Kit acl : For more details on each kit visit our website www.jaycar.co.uk arena FREE CALL ORDERS: 0800 032 7241Automotive Kits for Electronic Enthusiasts 410A 12VDC Motor Speed Controller Kit fe 2a High Performance Timer Cat. KC-5379 ‘Smart Fuel Mixture Display Kit Mixture Display Kit for Fuel for Fuel Injected Cars Injected Cars c 4 at. KC-5195 Bf Voltage Monitor Kit Cat. KC-5428 co [io en08 eapect Oday (9800032724 50,9999 10. for parcel 1612803231 :i09 e990 20 every techstoresiavcar.co.uk oe APS Track race eret| | post: P.O. Box 107, Rydolmere NSW 2116 Australia| sMorone 330m NO Pecae *AutationCstera Sender Tine sHeorerporeasPOA Sig conams day ioe ae BUR ae ecpaaaee ie Rial gore | aaa Soiae Sete (hed i 5 EG pp 2008 Vtamenin £31.88 savior" BRS Seont = = =~ Al Bs et 0099 Velleman hit £64.96 Ue Romo eB bo i tpctes M167 Modole 426.200 Ete Cobol Module (22.11 erie ow & se ac 1.10 Cabek Modelo £14.12 PRET yee ef ct Baty Sh Fir Tal 108A Key nsEDITORIAL tora Ones: EVERYDAY PRACTICAL ELECTRONICS EDITORIAL Winbome Pulsieg Us. 113 Lynne Dive. tig Wibore, Dorset BHOE TU Phone (0122) 8828 Fax: (01202) 3233, mal eniies@winborne cok “Wobate: aor ep Seo nes on Readers Technical Enqules biw wo rg chal ques carol be ansrered ‘vero were. Aovertisent Otioes: Everyday Pracical Bocrorics Ackericoraris ‘1a Lyrmood Drv, Mery, Wire, Dost peat Phone: 202 0299 Fx: 01202 642209, mal sowartkeam@uinborne cou tor MATT PULZER, ‘Consulting Eator: DAVID BARRINGTON, ‘Subscriptions: MARLYN GOLDBERG Genera Manager: FAY KEARN Graphic Design: RYAN HAWKINS EedtrilAdmin; (01202) 680055, ‘Advertising and Business Manager: STEWART KEARN (orate 20299 Omtine Editor: ALANWINSTANLEY Puttener: MIKE KENWARD READERS TECHNICAL ENOUIRIES mal techdopt@wirborracouk ‘Wearable ootrany scene use, pcs, repair or moat ef coreneal quent or Pe ‘eoperalon a modtcaion of dears mukened fe ragache. We regret tet we caret proce ats or anver ques on aries poets a re roe an the years 06 Loto egurrg a personal "epy mst be acconpaned by 2 sired sa _aessadenvoape oo ated eae and ‘erator ely coupons We are ot oo ane lec gute on he pore, PROJECTS ANO CIRCUTTS [At reasonable recatons ar akon ens hak [EPE employ votages at canbe lea You shoud rex, moa o renova ary bom of mas powered oqupere Urlss you uly untae Salty aspecsrvohed and youuse an RD adeno. ‘COMPONENT SUPPLIES We do nat supply lctonc camponerts rks or tudng tne projects feaved, the can bo supped yaar. ‘We ao reads o check hata pars ae Si aalabe bol conmoneng any projet aback Siedie ADVERTISEMENTS. Amough the props an sat of EVERYDAY PRACTICAL ELECTRONICS tke resonate pecans to protect the Inert of ado by eure sf a8 praca hat advorisomors ae bona, themapaahe ard ts puiharscart gre 2 underatings mn rspoc 0 skaonens or cars rade by advertears, wher theo adorisomors ‘eprd as prt te apace, on rss. “he Publishers ee ha unde ro creunsarces it Be magaane cca abay or reecage ‘rods orev. ore deve, Fors moter, ‘TRANSMTTERS.BUGSTELEPHONE Eoupuen We sven readers that catan tons of rado arsntieg and teophone ecipment wich may bm adrerind no pages caret be aga used the UK Renders shoud eck he ew ar Beg 2 Yaramting or elephone eauorer, 3s a tre, Catfcaton of equpmert ardor imereoreert an result rom legal use ner The ews ary tom ‘oun com eadorsshouscherk oc avs. VOL. 43 No. 03 MARCH 2013 EVERYDAY PRACTICAL ELECTRONICS Lightning, Daleks and accelerometers It’sa pleasure to welcome you to the March issue, which contains several projects I have been looking forward to for some time. Our Lightning Detector isa clever AM-radio project that looks for electromagnetic signals with a tell-tale ‘lightning signaturo’. It reminded me ofan Ingenuity Untimited submission, Atmospheric Charge Monitor - Aug ‘07 from our friend Thomas Scarborough. While this month's, and Thomas’ dosigns, work on very difforent principles, they both demonstrate the power of electronics to detect and measure the world around us with relatively imple circuits. Perhaps even more importantly, they could be critical in saving you from a very nasty zap when out golfing, hiking or sailing! Interplanetary Voice is one of those projects that is just plain fun. 'm certain it will be a sure-fire winner with younger constructors Ifyou are looking for a design to inspire and enthuse your children or perhaps students in a school electronics or technology club, then this could be the perfect choice. I just hope that too many parents or grown-ups don't live to regret supplying their young Daleks with a loud metallic voice remember, it does have an off switch! Great though these projects are, top of my list this month is the Digital Spirit Level. I's not that I have a large collection of sloping shelves and need to find a way to level them, but more about presenting you with a Circuit that uses a ‘micro electromechanical system’ ~ or MEMS for short. MEMS don’t receive the recognition they undoubtedly deserve. They aro essentially mechanical systems that have been miniaturised using microelectronic technology. The chip in the Digital Spirit Level is a clever three-axis accelerometer that costs less than the PCB, or project case. Before MEMS came along, accelerometers were expensive and relatively bulky dovices that could easily cost hundreds of pounds each. Measuring three axes typically required three accelerometers and the resulting cost and size made them unsuitable for hobby electronics. ‘The accelerometer's close cousin — the gyroscope — has also been miniaturised as a MEMS, and they are at the heart of the control systems of all those cheap radio-control toy helicopters that fly with remarkable stability. What accelerometers and gyroscopes do is allow a system to measure its own position, velocity and acceleration — both linear and in rotation —in three-dimensional space, a remarkable feat for such small, cheap devices. do hope we manage to provide more projects that use these fascinating devices, but in the meantime, do please have fun with our MEMs-based Digital Spirit Level,A roundup of the latest Everyday News from the world of electronics 0 @ OG HDMI protection compromised - by Barry Fox Time and. movio companies fare dead set on delivering entertainment online rather than on disc. The reasons for ‘going digital” are obvious; no physical produ costs, no warehousing, no delivery transport, no money to bricks- and-mortar middlemen and no returns. In pushing online delivery, the companies are assuming that ‘digital’ content is safe from easy home copying. thanks to the HDMI/ HDCP connection system. HDMI and protection HDMI (High-Definition Multimedia Interface) is like a digital SCART connector; one lead carries pictures, sound, data and Ethernet connec- tion. HDCP (High-bandwidth Digi- tal Content Protection) encrypts the HDMI signal. The HDMI devices at each end of an HDMI cable hand- shake to confirm security against copying before allowing the signal to travel Analogue component _ (YPbPr) cables can also carry Hi-Definition video, but have no copy-protection. High quality digital audio travels by SP/DIF optical or coaxial cable, which also has no copy protection. Several PVR (personal video re- cording) devices legitimately d tise and copy a Hi Def component signal, and SP/DIF digital audio stroam, to PC hard disk, eg, for cap- turing computer game play. US com- pany Hauppauge sells a PVR box with USB connection for around £150. This is why Sky HD satellite boxes no longer have component connectors, and why the PS3 con- sole disables its component output when playing movies. Cheap strippers For more than a year it has been easy to buy dovices, eg, through Amazon, that strip out HDCP copy protection and convert an HDMI signal to an un: protected camponent signal. So a Hi Def video signal can be captured like gameplay. The question is of course, how can such devices be sold? ‘The HDMI licensing organisation the HDCP tal-CP LLG, con giant Intel, ‘A yoar ago, digital content pro- tection administrator Cait would say only: ‘We are unable to provide a response to your ques- tions at this time.’ Now there are more HDCP-strip- pers on sale on Amazon, at ever lower prices (some under £30). The cheaper ones cope with only 720p and 1080i signals, while the more owned by sil ‘A cheap and easy-to-use HDCP copy protection stripping board, easily avaiable from Amazon 8 expensive versions handle 1080p full HD. The packaging is often go- neric. The devices need no set-up other than plugging between an HDMI output and component input. HDMI Licensing LLP admits it is now ‘frustrated’ by an apparent lack of policing action by DCP LLC. An ‘HDMI Forum’, made up of many large companies, has taken on. re- sponsibility for the HDMI techn cal specification. Just as happened with the Blu-Ray Disc Association, but getting a room full of companies and their lawyers to decide anything is like trying to steer an oil tanker round a bend. Stophen Balogh, of Intel, dent of DCP LLC. He says: ‘matter of policy...we don't comment on every claim or instance of HDCP circumvention, nor do we publicly spoculate on actions we may or may not be taking’ T purchased and stripped down a £30 stripper. A neat and simple PCB, obviously mass-produced in a com- potent factory, with a mix of off-the shelf and custom-designed, inscruta- bly and unclearly numbered chips. = vio21 = ADV7393/BCPZ- 3/W1203/2285920.1 SILICON IMAGE VASTLANE/ ‘Si19025CTU/VL8709.1/0831/ ‘ABOIMD2 = UCIML7F/SA11178H—3.3 = UCIMGCD/SA11178H-1.8 = ATMEL135/24C02N/SU27 D = 344C/1201 ‘The HDMI organisation says it is investigating the chip list, which I supplied them for comment. EPE readers may in the mea 0 to do their own investigations, and we would welcome letters and emails discussing th Everyday Practical Electronics, March 2013Ultra-low power converter boosts energy harvesting viplipeinguslgecniaae Tivsiodusty's lowest power DDC step-down converter, which increases tho amount of harvested energy an tend application can use by as much as 70% over alternatives. The resulting micro-power circuits allow battery- {ree power for mobile accessories and ‘wireless sensors which use microwatts generated from solar, thermoelectric, ‘magnetic and vibration energy. ‘This networks, monitoring systems, smoke detectors, and wearable devices. According to Sami Kiriaki, senior vice president of TI's Power Man- agement, “TI continues to develop circuits with very low operating cur- rent and high power efficiency that can manage microwatts to milliwatts and extract ambient energy. This new device gives designers capa- 8 not possible with traditional powered systems.” medi ‘The TPS62736 DC/DG converter delivers high power conversion ficiency from 10nA to 50mA out- put currents, and consumes only 850nA of active current and 20nA during standby. ‘The converter achieves greator than 90% efficten- cy across output currents higher than 15yA. The regulator steps down the voltage from a power source, such as a thin-film or reg- ular battery, or a super capacitor, and features a programmable ou put voltage. The TPS62736 is the latest in a s0- ries of low-power devices from TI In 2014, it introduced its bq25504 boost charger circuit with a low qui- escent current of 330nA, to allow startup from single-cell solar cells under low light, or thermoolec generators with low temperature differences. More details about low-power DC/DC converters wailable at: www.ti.com/power-pr Ubuntu OS goes mobile ‘The Ubunau operating system comes to Android smartphones Chama Le, the Ukcbused software company that created and distributes Ubuntu, a free, popular desktop Linux-based opera- ting system (OS) has announced a smartphone interface for its OS. Ubuntu is now compatible with a typical Android smartphone, which moans itis ready to run on what they claim is ‘the most cost-efficient chip- sot designs’. The objective in bring- ing Ubuntu to the phone is for users to have a single operating system for client, server and cloud. and a unified family of interfaces for the phone, the PC and the TV. “We are defining a new era of convergence in technol- ogy, with one unified operating sys tem that underpins cloud comput- ing, data centres, PCs and consumer electronics” says Mark Shuttleworth, founder of Ubuntu and vice president products at Canonical Over 20 million desktop PCs current ly run the frve OS, and Canonical esti- mates that close to 10% of the world’s new desktops and laptops will ship with Ubuntu in 2014. Ubuntu is also popular as a server platform, and the number one server OS on key jor public clouds, Both Ubuntu and Android run at the same time on the device, without emulation or virtualisation, and without the need to reboot. This is possible because both share the same kernel (Linux) Unlike Apple's i0S_ system for iPhones, mobile Ubuntu is a full PC operating system. Canonical has stated that, ‘tis able to offer a com: plete platform because phone CPUs can now run a complete desktop en- mple, Ubuntu will run on low-end 2013 phones released with a dual: core Cortex A9 processor run 1GHz, and with 512MB RAM. Mod- cern processors in mobile phones of- ten have multiple cores and Ubuntu apps are designed to use all avail: able modern cores. Ubun ude both the Chro: mium and Firefox browsers for easy and familiar web uso, Native app developers will be able to use Canonical’s software develop- ment kit (SDX) for Ubuntu, which makes it easy to create apps that per- form on a wide range of hardware and form factors, More information is available at Everyday Practical Electronics, March 2013 1BM 90nn silicon integrated nanophotonics technology is capable of imegrating «pho tadetecior (ed feature on the left ide of the Cue) and mandate feature om the ight sie) fabricated side-by-side with silicon tan sists. Silicon nanophotonics cies ands fom transistors are interconnected with vine levels yellow metal wires BEM amano a major advanca jin the obility to use light instead of electrical signals to transmit information for future computing. The breakthrough technology — called silicon nanophotonics’ — allows th integration of different optical components side-by-side with electrical circuits on a single silicon chip using, for the first time, sub 100nm semiconduetor technology Silicon nanophotonics takes advan- tage of pulses of light for communica- tion and provides a super highway for large volumes of data to move at rapid speods between computer chips servers, large datacenters, and. super computers, thus alleviating the limi tations of congested data traffic and high-cost traditional interconnects. ‘This technology breakthrough is a result of more than a decade of pioneering research at IBM,” said Dr John Kelly, senior vice president and director of IBM Research. "Thi allows us to move silicon nanopho: tonics technology into a real-world manufacturing environment that will have impact across a range of applications.” COMMONER RARE EARTHS Fro star beams to oxticrngnets, th arth’ elements are a parti strategically useful, ingredient in modern engineering recipes. Despite their name, they are not particularly rare, but mining them can be very environmentally hazardous. Now, ‘almost the only country that extracts them (95% of world production) is China, The US has decided it does not wish to let China have near total control over such important minerals d has sot aside $120m to enable US mines to develop safe extraction techniques on US soil.Constructional Project Wailea coi SN Mele fe... bY outdon: tiwant tojbe, en in pec ca oh e refiste @ pve Detector -~ ft ee Ce rt ote or eet derstorm is on the way. If there is a strike nearby you could be in big danger of death or injury. And you don't have to be hit directly — induction can kill you and so can the voltage gradient across the ground in Pere Rees urn ten (oni Ae eee are ng Clarke after storms, and just about all of this could be avoided simply by switching off and removing power plugs from ise) Those appliances especially at risk include microwave ‘ovens, TV sets, satellite receivers, mains-powered comput- cers (especially those also connected to the phone lines via They should not be just switched off at the power poin Sen df eee ee COs and power to these can be switched Apart from mains-powered computers een ir CiernyOf course, it is well known that any phones (apart from mobiles and cord- less models} should not be used during «a thunderstorm. ‘So what to do? To got a warning of imminent thun- derstorms, you need our Lightning Detector. It is a pocket-sized unit that provides visual indication using a flashing LED and sounds an audible tone whenever lightning occurs in your area, The greater the number of lightning strikes, the more LED flashes and audible tone bursts are produced, For portable use, it's powered by two alkaline AA cells and the battery fe should be at least 1000 hours. For ndoor use, you can use a 6V to 12V 1: block diagram of the Lightning Detector. The early part looks similar to a radio receiver - which of course it ‘one thing: the RF pulse from a lightning strike within range = but this radio receiver picks up just DC supply. such as a plugpack. One resistor needs to be chosen according to the DCsupply voltage. When the external power supply is connected to the jack socket, the AA cells are automati- cally disconnected from the circuit ‘The principle of operation is based on detection of the broad-spectrum electromagnetic emissions produced by lightning strikes. This is readily detected by a simple AM (amplitude modulation) radio receiver, If you've ever been anywhere near an electrical storm with an AM radio turned on, you'll have heard the crashes (static) of lightning strikes. Very large strikes can be heard from a considerable distance away We use a single AM radio IC, which comprises an RF (radio frequency) amplifier, detector and AGC (automatic gain control). This was originally available in 1984 from Ferranti Semiconductors as the ZN414Z, but replaced by the MK484, now also obsolete. ‘We have used the modern equivalent, the TA7642, It op- ‘rates from a 1.2V to 1.6V supply, and covers from 150kHz to 3MHz, This includes the normal AM radio broadcast band (530kHz to 1.6MHz), but for our purposes, we are not concerned with listening to broadcast radio stations, ‘We simply monitor the whole spectrum covered by the AM radio chip. Block diagram ‘The general arrangement ofthe Lightning Detectors shown in the block diagram of Fig.1. IC1 receives signals from a pickup coil, In an AM radio, this pickup coil would nor- mally be tuned to a particular frequency using a variable ‘tuning capacitor. We want to monitor a wide frequency range, and so the coil is Jeftuntuned. IC1's output signal is noise bursts from lightning. Output from IC is typically 15mV with a tuned coil, but is around 2mV with the untuned coil. This signal isamplified using transistor Q2 and asonsitivity con- trol (VR1) sets the level applied to the following pulse extender, Features Portable Sensitivity control Battery condition Reverse supply Everyday Practical Electronics, March 2013 Battery or external power supply Visual and audible lightning indication comprising IC2 and diode D3. When lightning is detected, ‘a noise-burst triggers the pulse extender. The pulse extender produces a 200ms pulse and this lights the ‘detect” LED (LED1). The pulse extender is nec- essary because the lightning strike pulses are too short in uration to be noticed as a flash from the LED. IC3 is an oscillator that runs for 200ms each time the pulse extender produces a low signal and the resulting kHz tone burst drives the piezo transducer, which is resonant at that frequency. Circuit detal ‘The full circuit is shown in Fig,2. As mentioned, IC! is the ‘TA7642 AMradio chip, while CMOS 555 timers are used for the pulse extender C2 and for the 4k¥¥z oscillator, IC3, The it is powered from 3Y, but it will operate down to 2V, ‘A1.5V regulated supply powers IC1, while the amplifier, pulse extender (IC2) and oscillator (IC3) are driven from the 3V supply While most of the circuit is powered from the 3V supply rail, IC1 needs to be operated at between 1.2V and 1.6V, To provide for this, we use a voltage regulator comprising Qt and two infrared LEDs (LEDS and LEDS). These develop a forward voltage of approximately 1V each, which is remarkably constant over a wide range of current. Tests of several infrared LEDs from different ‘manufacturers showed that the forward voltage is around 1,09V at 1.6mA, dropping to 0.945 at 160,A, ie, a cur. rent range of 10:1 Stacking two infrared LEDs in series provides a reason- ably stable 2V reference. The LEDs are fed via a 2,2k0 resistor from the 3V supply. and the 2V refer- ‘ence drives the base of transistor Q1. This acts as @ current buffer to supply IC1 with about 14V, This varies from 1.46V with a 3V supply down to 1.287V with a 2V supply. ICI is connected to the 1.4V supply via the 4700 AGC resistor ictorFig. you use LIGHTNING DETECTOR Se the three main functional areas of the circuit diagram are labelled the same as the block diagram to enable you to trace the circuit operation. As mentioned in the text, resistor R1 needs to be selected depending on the DC power supply can handle anything from 6-12V. The battery supply is nominally 3Y, but it will operate down to 2V. atitsoutput pin. A 100nF decoupling capacitorat the output sets the high-frequency rolloff to 4kH ‘One end of pickup coil Li is connected to the high impedance (around 3MQ) input of IC1, while the other end is grounded via a 100nF ceramic capacitor. There is no parallel capacitor across L1. This means that the coil is untuned and will have a broadband response. Bias for tho input of IC1 comes from a 100k resistor connected to its output. ICI’s output is AC-coupled to the following common- emitter amplifier, Q2. This has its emitter resistor bypassed with a 22nF capacitor to provide a gain of approximately 50 for frequencies above about 723Hz. Q2’s collector load comprises the 10k potentiometer VR1 and a2.2k0 resistor. VR1 is the sensitivity control IC2and IC3 areCMOS 555 timers, and most manufacturers of these devices state that their version will operate down to 2V or less. These include the Intersil ICM7S55IPA, Texas Instruments TLC555CP, ST Microolectronics TSS55GN and National Semiconductor LMC5S5CN. The NXP (founded by Philips) ICM7555CN guarantees operation at 3V over full automotive temperatures. However, performance graphs show operation witha 2V supply at~85°C, 25°Cand 125°C, Also, samples of the NXP ICM7555CN operate successfully at 2V, and we are inclined to assume that this IC does also operate at 2V. Specification Frequency detection band: 150kHz to 3MHz Make sure you do not use bipolar 555 timers such as, the LMS55CN or the TLSS5CP: these typically require 4.5V or Supply votage: 8V (2 x AA calls) — will operate down to 2V snore Sur operation: Plugpack, 6y to 12V DC at 30mA 1C2 is the pulse extender, which is set Current consumption; Battery operation is 1.5mA at V, 1mA at 2V, upas a monostable timer. Before triggering DC plugpack operation is 17mA at 12V ‘occurs, pin 3 is close to OV and the 470nF Battery tte: Typically 1000n with alkaline cells Capacitor is held dischargod at about 0.6V Typically 1.46V with SV supply, 1.28V with 2V supPIY | above OV by diode D3. Pin 2 is held at 45% Bown 0 2 of the 3V supply, ie, at +1.35V, using the ae eons 220k8 and 180K02 voltage divider resistors. ‘Triggering occurs when the noise signal fod to pin 2 pulls it below +1V. This sots Everyday Practical Electronics, March 2013Fig.a: everything (except the batteries) mounts on ingle-sided PCB. End Panel Drill Guide ‘The component layout is shown above and, with the same-size photo at | right, is self-explanatory. Fig.4 (right) is the drilling guide for the end panel. There is no labelling on this diagram; all controls are labelled on rao te Switch ‘smm 7mm the front panel 3mm 3mm pin 3 high and diode D3 is then reverse biased. The 470nF Capacitor then begins to charge via the 470k0 resistor, During this time, LED1 is lit (driven from pin 3). When the voltage across the 470nF capacitor reaches 2/3 of the supply voltage, pin 3 goes low and the 470nF capacitor is, discharged via diode D3. ‘Thisis an unconventional monostable timer arrangement Normally, pin 7, the discharge, would be connected to pin 6and would discharge the 470nF capacitor instead of using diode D3. Using D3 to discharge the capacitor frees pin 7 to perform another task. Because it can sink (pull down) to OV, it is suitable for use as a reset control for the following oscillator, IC3. 1C3 is connected in astable (free-running) mode, run- ig at about 4kHz.to drive the piezo transducer. It is held in the reset condition, with its pin 4 pulled low by pin 7 (discharge) of IC2, when IC2 is not timing. Power supply As already mentioned, the Lightning Detector is powered from two AA-colls ora low voltage plugpack supply. When running from the AA cells, current flows via the closed contact in the power connector (CON1) and through the 220 resistor to the OV supply. This resistors included to prevent excess current if the cells are inserted back-to-front. When. the cells are correctly inserted, the 220 resistor produces Everyday Practical Electronics, March 2013 a minimal voltage drop (normally less than 33mV and less than 100mV with the detect LED lit). When running from a DC supply, the AA cells are discon- nected via CON1 (as noted earlier) and the incoming supply isregulated down to3.9V using Zener diode ZD1 and resistor R1. The value ofthis resistor dopends on the DC supply volt- ‘age—anywhere from 6V to 12V will be suitable, with resistor ‘values of 1208 (6V), 3300 (9V) oF 4700 (12). The negative supply connects to the circuit ground via the 220 resistor. Diode D1 reduces the 3,9V Zener voltage supply to about 3.3V, We could have used a 3.3V Zener diode on its own with- out D1. However, we want to be able to run the circuit from two AA cells that provide a 3V supply. Ifa 3.8V Zener diode ‘were used, the cells would be discharged via the Zener diode. So, by including diode D1, current is prevented from flowing through the Zener diode. The Zener voltage is increased from 3.3V to 3.9V to compensate for the 0.6V diode drop. D1 also blocks reverse voltage to the circuit should the 12V supply be connected with reversed polarity. With reverse polarity, Zener diode ZD1 is forward biased and clamps the voltage to no more than ~0.6V below the OV supply. D1 stops current flowing through the circuit backwards. Battery indication When the power is first switched on, LED2 provides in- ication of the battery condition, LED2 is driven via PNP 1BParts List — Lightning Detector 1 PCB, code 888, 65mm x 86mm 1 remote control case, 185mm x 7Omm x 24mm. 1 panel label, 50mm x 114mm 1 miniature PC-mount SPDT toggle switch (Altronics $1421 or equivalent) (St) 1 knob to suit potentiometer 1 switched 2.5mm PCB mount DC socket (CON1) 2 AAalkaline cells, 28 -pin IC sockets (optional) 4 tuning coil with ferrite rod (Jaycar LF-1020 or similar) 1 low-profile piezo transducer 2.6mm spacers 2M25 x 12mm screws 4.6mm self-tapping screws 2.100mm cable ties 6 PC stakes 11 50mm length of red light gauge hookup wire 150mm length of black light gauge hookup wire Semiconductors 1,TA7642 single chip AM radio (IC1) (www.conrad-uk. ‘com or eBay) 2.7555 CMOS 555 timers (ICM75SSIPA, TLC55CP, TSS55CN, LMC5SSCN or ICM7555CN) (IC2,IC3) 2.3mm high intensity red LEDs (LED1, LED2) 2.5mm IR LEDs (LED3,LED4) 1 BC547 NPN transistor (Q1) 1 BCS49C NPN transistor (Q2) 1 BC559 PNP transistor (03) 1.3.9V 1W Zener diode (ZD1) 2.1N4148 signal diodes (D1,D3) 41 1N4004 rectifier diode (D2) Capacitors 2 10uF 16V PC electrolytic: 1.470nF MKT polyester 4 100nF MKT polyester ‘ Roproduced by arrangement 2 400nF ceramic ‘with SILICON CHIP 1 22nF MKT polyester ‘magazine 2013. 1.10nF MKT polyester ‘www.sillconchip.com.ax 1 nF MKT polyester Resistors (0.25W, 1%) 1470K2 —-2220K2 2 180K $100k 1 10k 222k 11kQ 1470211801220 4 of 1209, 3309 or 4702 0.5W (Rt ~ see text) 1 10k01 log potentiometer, 9mm square, PCB-mount transistor Q3 and its base (B) is initially tied to OV via the 10nF capacitor. With the supply at 3V, Q3’s emitter is at about 0.6V and the LED is driven at maximum brightness. That is with about 2.4V (8V ~ 0.6V) across the LED and 100 resistor. Assuming an LED forward voltage of 1.8V, this produces a current of about 3mA Ata lower supply voltage, the initial LED current is less and it willbe dimmer. With a 2V supply, LED2 will bebarely alight, indicating that the batteries should be replaced. Whatover the supply, LED2 only lights momentarily and as the 10,F capacitor begins to charge via the 100k 4 Here's how the PCB fits inside the case. The top corners need to be shaped to fit the case mounting pillars, but otherwise it's a simple drop-in fit, secured by four self- tapping screws. The two AA batteries which power the unit fitunder the moulding at the bottom resistor, itdimsand eventually goes out. The 220k resistor across the 10uF capacitor prevents the capacitor charging to any more than 2/3rds the supply. This provides a faster discharge of the capacitor when the supply is switched off ‘The 2200 resistor is also used to discharge the capacitor when the supply is off, soit is ready to flash the LED when power is reapplied. Construction ‘The Lightning Detector uses a PCB measuring 65mm. x ‘86mm and is coded 888, This board is available from the EPE PCB Service. The topside component layout is shown in Fig.3. The PCB and components are housed in a plastic. case measuring 135mm x 70mm x 24mm. ‘The PCB is designed to mount on to the integral mount- ing bushes within the box. Make sure the front edge of the board is shaped to the correct outline so it fits properly. It can be filed to shape if necessary, using the PCB outline shape as a guide, Begin construction by checking the PCB for breaks in tracks or shorts between tracks or pads. Fix any defects, if necessary. Check the hole sizes for the PCB mounting holes and for the cable ties. These are 3mm in diameter. You can then insert the resistors. Use the resistor colour do table to select each value or, better still, check each one with a digital multimeter. Then install the diodes; they ‘must be mounted with the orientation shown. Install the six PC stakes. ICz2 and IC3 can be mounted on sockets or directly sol- dered to the PGB, When installing sockets and ICs, take care to orient them correctly —as indicated by the notch at one end see Fig.3. Everyday Practical Electronics, March 2013‘The capacitors can be mounted next. The electrolytic types must be oriented with the shown polarity. Make sure these capacitors are placed on the PCB so their height above the surface is no more than 12.5mm; otherwise, the lid of the case will not fit correctly. ‘Note that while provision is made for a capacitor across coil L1, one is not used in this circuit (as montioned earlier). Itis included so that you can experiment with the radio IC. by placing a tuning capacitor between the two PCstakes for coil Li and placing a fixed-value (if required) capacitor to pad out the capacitor range, This will allow the recoption. of radio broadcast stations. ‘The audio signal will be available at VR1's wiper. A cou- pling capacitor (say 100nF or so) is required to connect this signal to an external amplifier. ‘Now mount IC1 and the transistors, taking care to place each in its correct place. If you happen to be using a Fer- ranti ZN414Z, from your IC collection for IC1, note that the GND and OUT pins are reversed compared to the specified TA7642. You would also have to place the IC in the PCB oriented 180° to that shown on the overlay. ‘An MK484 has the same pinout as the TA7642. The ‘TA7642 has a greater sonsitivity in the lightning detector application compared to the MK484 and sogiven thechoice, ‘werecommend using the TA7642, We did not try aZN414Z, since this is no longer available. ‘The potentiometer (VR1) and PCB-mounted switch $1 ‘can now be soldered in. LED1 and LED2 are next. These mount horizontally, butata height of 6mm above the board surface. Bend their leads 90° at 7mm back from the base of the LEDs, m {ng sure the anode (A) lead is to the left Detector coil L1isastandard broadcast band coil pre- ‘wound on to a small ferrite rod. There are actually two coils on the rod, but only one is used. Using your multimeter, find the coil that has the greatest resistance. With our prototype, the main winding measured about 11, while the separate antenna winding measured 20. Connect the coil, with the highest resistance to the PC stakes. The ferrite rod is secured to the PCB using a pair of small cable ties ‘The piezo transducor is mounted us ing two 6mm-long standoffs and M2.5 x 412mm screws. The screws are inserted from the underside of the PCB, pass through the spacers and tap into the 0 mounting tabs. If you are using a Aifferent piezo transducer that has larger ‘mounting holes in the tabs, M3 screws could be used instead to tap into the plastic transducor tabs. Alternatively, two nuts can be used. Follow the wiring diagram to make the connections from the piezo transducer and battery terminals to the PC stakes ‘on the PCB. Fig.5: this same-si and printed, then Everyday Practical Electronics, March 2013 Bi Anta Detter ‘can be photocopied or downloaded Thisend-on view shows the two controls and two LEDs which ‘mount on the end panel Next, install the battery clips into the battery compart- ment. The two connected terminals are placed on the ight-hand side (as you look at the rear of the case with the compartment at the bottom). The spring terminal is placod to the top and the raised section to the bottom, For the left side, insert the separate terminals with the spring terminal placed at the lower edge and the raised section to the top. ‘The next step is to bend the two individual terminals to the outside of the compartment. You may need to stretch the contact springs so that the AA cells are held securely between the contacts, ‘The PCB is secured to the base of the ‘case using four M3 x 6mm screws that screw into the integral mounting bushes in the box. Before fitting them in place, drilloutthe small front panel for the LEDs, potentiometer and switch. Fig4 showsthe drilling template and this can be copied and atlached to the panel during drilling ‘The panel label for this project can either be photocopied (see Fig.5) or for best results, it can be downloaded from the EPE website (www.epemag.com), When downloaded, print it on to paper, sticky-backed photo paper or plastic film. For protection and long life, paper labels should be covered with cither self-adhesive clear film oF (as we normally do) hot laminate it (laminators and slooves are vory choap these days and give a tough protective lay If printing on clear plastic film (over- head projector film) you can print the label as a mirror image, so that the ink is behind the film when placed on to the panel. Again, this will give the label maximum protection. Once the ink is dry, cut the label to size. Tho paper or plastic film is glued to the panel using an even smear of neutral- ‘one. For plastic film, if you are gluing it to a black-coloured panel, use coloured silicone such as grey or white, sothe label can be seen against the black. ize panel artwork ‘glued in place 15RESISTOR COLOUR CODES 4-Band Code (1%) yellow purple yellow brown brown red red yellow brown brown grey yellow brown brown black yellow brown brown black orange brown red red red brown brown biack red brown yellow purple brown brown 1802 brown grey brown brown 220, red red black brown ‘of the following (1) 1 4700 yellow purple brown brown 1 3302 orange orange brown brown 10K02 22k 1k 4700. oogooocooeco o Oo 1200 brown red brown brown, ‘Ahole in the panel is required directly above the piezo transducer. This can be first drilled in the plastic lid and then once the panel label is affixed, cut the hole out u a sharp hobby knife. A small piece of dark fabricor loudspeaker foam (scrounged from an old pair of headphones) can be used to cover the piezo transducer. Also, a black bezel over the panel hole can improve the finish of the unit. Theseare secured with asmear ofnoutral cure silicone, Our bezel came from the plastic dress plate that sits behind the nut of a stereo 6.35mm jack socket. What to do in a storm ‘The best idea is to avoid getting caught outside in an electrical ‘storm, but sometimes, the best laid plans of mice and men...etc. How far away is the lightning? Watch fora flash of lightning. Then count or read off your watch the numberof seconds until you hear the first erash of thunder (or crack if ts close). Divide the number of seconds by three and you have a rough distance to where te lightning has stuck. Anything less than ‘hm i, 3s) should be regarded as geting very dangerous, 4M you cannot get to shelter? Ityou are caught outside during an electrical storm, avoid conduc- ‘tors of electricity such as water, trees, poles, golf clubs, umbrellas and metal fences. {t possibe, keep away from open spaces (eg, the middle of a ‘sports field) where you will be taller thar ‘Surroundings and definitely do not shelter under a tree. Crouch down, keeping your feet close together and wail out the storm. Groups of people should be spread out several metres apart. ‘tis also a good idea to cover your ears with your hands to avoid hearing damage due to the noise of a close lightning strike, ‘IM possible, take refuge inside a vehicle or building. It inside a vehicle, close the windows and avoid touching the metal of the vehicle. Make yourself less of @ target by lying down (eg, on the ‘back seat). Keep the vehicle away from trees or tall objects that over in the storm. Avoid fallen power lines. S5-Band Code (1%) yllow purple black orange red red black orange brown brown grey biack orange brown red red black brown brown, brown black black brown brown, ‘yellow purple black black brown brown grey black black brown red red black gold brown ‘yellow purple black black brown ‘range orange black black brown red black black brown Additionally, a cut out is required for ‘acoess to the DG socket. A rat-tal file can be used to make this hole in the lid Testing ‘Testing can be done with two AA cells or DG supply. Apply power and check that the power LED momentarily lights when the Lightning Detector is switched on Check the supply voltage by measuring across diode D2. This should be around 3V, but may differ depending on the stato of the cells or the tolerance of the 3.9V Zonor diode when a DC power supply is used. The voltage across the 220 resistor should be about 33mV with a 3V supply. or less with a lower voltage supply. Chock the supply to IC1 at the emitter of QL. This should be 1.46V with a 3V sup- ply, dropping to 1.287V with a 2V supply. Adjust the sensitivity control fully clock- wise or back off if any indication persists. You can now test the Lightning Detector as fluorescent light is switched on. Conventional fluores tubes will cause the Lightning Detectortogivean LED detect 1d tone indication as each starter attempts to light its tube. By contrast, compact fluorescent tubes tend to be indicated with a single flash and tone as the tube lights rapidly. “The sonsitivity control is included to provent the Ligh ning Detector from producing an indication when there is no lightning. ‘The control is adjusted clockwise for maxi- mum sensitivity to lightning, but not so far as to give false detection. EPE Inside a building, keep windows and doors closed and keep ‘away from windows, doors and fireplaces. Before the storm, unplug electrical appliances that may be susceptible to lightning damage. These include fax machines, telephones, microwave ‘ovens, televisions and computers. To be doubly safe. unplug any. ‘computer communications devices from phone lines or cables (don't forget routers) ‘Avoidusing electrical appliances and telephones until the storm ‘has well and truly passed, However, you can use a mobile phone ‘you have to, eg 0 cal for help. Avoid touching earthed fittings, such as water taps, sinks, appliances and so on. {you are ona oat, keep low, dry and away from metal conduc- tors. Always check with the Met Office for storm forecasts before going out on a boat. in this way, you could avoid boating in a storm, ‘Ifyou are a boat owner, make sure the boat is fitted with lightning protection that crects lightning salely to the water. This wil telp ‘Protect the occupants should they be caught out ina storm and also. ‘help protect the boat when left moored. If someone near you is struck by lightning? Avoid the temptation to rush in and help — time is of the ‘essence, but there's no point in two people being struck! As soon as itis safe to do so (ie, the danger has passed), com- rence standard A-B-C resuscitation. Check their response, clear ‘the airway, and if necessary proceed with CPR. ‘What? You don't know CPR? Learn it today! Everyday Practical Electronics, March 2013Wina ihileroetnli—y MUP 8=Bilt Development Board r PR ) is offering its readers the chance to win a Microchip XLP 8-Bit Development Board (DM240313). The XLP 8-bit Development Board provides a low-cost, highly configurable, development system for Microchip’s new line of extreme-low-power 8-bit PICI8F or PICI6F enhanced core microcontrollers that allow for design of sleep currents down to 20nA. The board supports development for the PIC18F87K22 or PIC1GLF1947 MCUs, which highlight the capabilities of each product family Tho board can be powered by five different power sources, including batteries or energy harvesting modules (sold separately), and it supports a variety of common components that can be selective ena- bled. The board is also expandable through the on-board PICtail connector that permits the addition of capabilities such as RF connectivity. The kit includes a USB cable, a power measurement cable, a Quick ‘Start guide and a PIC16LF1947 PIM. ‘The board is suitable for prototyping many low-power applications, including RF, temperature sensors, electronic door locks, LCD, remote controls, security sensors, smart cards, and energy harvesting. The PiCtail interface supports Microchip's extensive line of daughter cards for easy evaluation of your next low-power application. For your chance to win the XLP 8-Bit Development Board from Microchip, please visit: www.microchip-comps.com/epe-xlp8, and enter your details in the online entry form. ‘The closing date for this offer is 31 March 20137 Ue Cea Ard Part 2: By JIM ROWE Check all those semiconductors in your collection with this easy-to-build test set! This month, we present the full circuit of this versatile unit, which can test all the discrete semiconductors in your collection. It employs a PIC16F877A microcontroller to run all the different tests, and displays the results on a 2-line LCD panel. PICIGF877A beca © Relay 1, which is used to: lay 7, which controls the value volt Most of these are on the upper PCB put four relays are on the main board: 18 Everye ies, March 2013Connections to the relays on the upper PCB are made via CONS and CON4 Bit lines RCO to RC3 of port C, to- gothor with REO and RE1 of por E, aro used tocontrol the LCD module, which is again on tho upper PCB. These con- nections are made via CON2, which links to CONS on the upper board via @ 10-way IDC ribbon cable. ‘The remaining bit lines, RC4 to RC7 of port C, plus bit line RE2 of port E are used to monitor activity on the five pushbutton switches S3 to $7. These ‘mount on the instrument's front panel and are connected using 16-way IDC ribbon cable from GON? on the upper PCB to CON4 on the main board. ‘The same connectors and cable are used to makethe connections forrelays 3 to 6, 9, 15 and 16, plus the connec- tion for LEDI (the ‘Test Volts Present indicator) High-voltage supply The test voltage power supply cir- cuitry at upper loft on Fig.5 has been adapted from the high-voltage por supply in the Electrolytic Capacitor Tester/Reformer described in August- September 2012, Asbefore,the supply isastep-up DC- DC converter using IC: (an MC34063) as the controller, with transistors QU and Q2 used to drive MOSFET Q3 and transformer T1. The ‘flyback’ voltage pulses developed by Tt are rectified by fast diode D2 and fed to the output filtering and current-limiting circuitry The MC34063 maintains the output voltage at the selected level by means ‘of negative feedback from the four 75k resistors in series with trimpot VR1 in the top leg, plus the 100k0 resistor connected from pin 5 of IC1 to ground as the ‘default’ bottom leg. This basic divider determines the converter’s nominal ‘10V' output level ‘The three other operating test volt: ‘ages (25V, 50V and 100V) are achieved using switch S2a to bring other resist- ‘ances in parallel with the 100k9 lower resistor, while relay 2{a) is used to achieve the converter’s much higher {about 600V) ‘BY’ output voltage by switching in a 6809 resistor across the 100k® resistor instead. ‘Trimpot VR1 is used to set the converter’s OPV output voltages precisely. Bit lines RA4 and RAS of, the micro’s port A aro used to sense the setting of switch S2, ie, via poles S2b and S2c. Everyday Practical Electronics, March 2013 Main Features ‘A compact yet flexible test set for most common discrete semiconductor de- vices, including diodes (unction and Schottky), LEDs, Zeners, diacs, bipolar junction transistors (BJTs), MOSFETs, SCRs and thyristors (including triacs). Based on a PIC16F877A microcontroller, with dovice and test selection, plus the test results displayed via a 16:2 alphanumeric LCD readout. Devices to be tested are connected tothe test set via an 18-way ZIF socket. Five test voltages are available: a 600V source for avalanche breakdown (BV) testing, plus a choice of either 10V, 25V, 0 or 100V for operating voltage (OPV) tests, Altest voltages are applied to the DUT via current-limiting resistors 100k in the case of BV tests or 2k0 in the case of OPV tests. Maximum avalanche current which can flow during BV tests is 6mA (short circuit current ‘Maximum device/leakage current which can flow with OPV = 100Vis 30m; with OPV = S0V is 25mA; with OPV = 25V is 12.5mA; and with OPV = 10V is 6mA. Minimum leakage current which can be measured = 1) Diode tests (1) Reverse avalanche current Ip (BV) (2) Reverse leakage current In (OPV) (3) Forward voltage drop Ve (OPV) (4) Zener/avalanche voltage Va (BV) LED tests (1) Reverse leakage current a (OPV = 10V) (2) Forward voltage drop Ve (OPV) BJT tests (1) Breakdown voltage C-8 with emitter of¢ Vienjos0 (2) Breakdown voltage C-E with base o/c Viepjceo (8) Leakage current C-B with emitter of¢ Ioao (OPV) (4) Leakage current C-E with base o/c Ioeo (OPV) (5) Forward current gain hee with a choice of three base current levels: 201A, 100}A oF 500»A Maximum he which can be measured with Ip = 20A is 1500 (OPV = 100V) Maximum hee which can be measured with Ip = 100A is 300 (OPV = 100V) Maximum hee which can be measured with |g = 500A is 60 (OPV = 100V) MOSFET tests (1) Breakdown voltage D-S with G-S shorted Viemjoss (2) Leakage current D-S with G-S shorted Ings (OPV) (8) D'S current Ips versus G-S bias voltage Ves (le, gm) ‘SCR, PUT and triac tests (1) Breakdown voltage with G-K (SCR) or G-A (PUT) shorted Vieryaxs (2) Leakage current with G-K (SCR) or G-A (PUT) shorted lags (OPV) {@) Current Inxs with gate current applied (20¥A, 100)/ or 500wA) and OPV applied (4) Voltage drop A-K when conducting Vax (OPV) Roproduced by arrangement with SILICON CHIP magazine 2013. wwrsiliconchip.comau Note: the test set operates from an external power source of 12V DC. Current drain varies from around 65mA when a testis being set up, to a maximum of approximately 900mA during testing. It can, therefore, be powered from either a 12V SLA battery or a 12V/1A mains power supply or regulated DC plugpack.