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With an impressive 3300 lumens, this spotiight is ideally suited t0 search and rescue, boating, professional^ shooters, security or other h¡gh-power applicati0ns lt's housed in a tough weather-resistant AtsS housing and has a handy shoulder strap for extended use. The builljn rechargeable battery g¡ves^ about 50 m¡nutes of continuous use and it recharges ejther from the mains plugpack (^) 0r a car cigarette lighter socket
This mulli-band pocket radio has digital tuning and has a large backlit LCD. lt features full clock functions w¡th an alarm and receives AM, FM and SW o (^) Dimensions:112(H) x 70(W) x 24(D)mm o (^) Power: 4.5VDC plugpack (^) or 2 x AA batteries
A robust LED work light with a magnelic base and hanging hook which makes it ¡deal for emergencies or boating and camping etc. lt has a 30 LED work lìght mode and a single LED torch mode lvla¡ns plugpack (^) and car charger ¡ncluded.
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. (^) iPod@ not included
MEDULATER
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Watch movies on your in-car TFI mOnilor 0r ¡isten to your favourite ¡/P3 (^) tracks on your (^) FM radio Simply plug (^) into your car cigarette lighter outlet & c0nnect to your (^) mOnit0as A./V input, 0r transmit the audio by FM to your stereo.
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. (^) Dimensions: 235(H) x g5(d¡a)mm
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Learn where all the important organs in the body are and how they all ¡nteract with each other. This highly detailed model shows all the main organs and they can be dispiayed in cutaway (^) or complete, You can remove any of the organs and look ¡nside (^) them to see what goes where and why The complete model is 2.5:.lscale and is 380mm tall, A fantastic eduøtional tool for home, science lab 0r educat¡on for all ages. o (^) Recommended for (^) ages 8+ Full tange of human (^) & animal anatomy models ¡n s
it (^) øn run from ordinary batteries. Simple and safe for ages 8+.
. (^) Requires 2 x AA batteries for no-solar operation.
and will inlroduce your child to the eco-fr¡endly concepts in a decept¡vely entertaining way. lt has it own solar panel^ and a windmill to supply free power t0 the light¡ng & sound circuits, or
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Universal
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- lnput: 100-240VAC
- (^) Output: 12VDC (^) @
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LGD Mounting Bracket (with removable pin)
^- Colour: Silver^ /^ Grey
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- Maximum Load: '15K
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PHOENIX High Definition
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Military Style Lensatic Compass
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Type: Non - lnductive Size(LxDmm (^) ): I 25x
lnput impedance: >100MOhm Supply voltage: 7-11V DC Power consumption: lmA DC Over-range indicator:'1'
Decimal place:^ Selectable with. -'!t !;5--0-.-]
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Lead-Free Adjustable
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Features: For general electronics
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With on/off switch & LED indication Standard tip: I 2mm Specifìcations: Heater Power for Soldering lron: 48W Temperature Range: 100 (^) - 450 Deg .C Voltage Supply: 220 - 240VAC Weight: 0 59kg
12VDC Revolving Warning Light
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lllli (^) fs¿¡5 ef
llli Drivino
llll lnnovãrion
siliconchip.com.au DECEMBEN 2OO
Praise fot the
WIB project
I have been^ looking^ for^ something
like the WIB project for quite^ a^ while, To make it abit more^ versatile^ could
you please make^ the digital^ outputs
configurable as^ either^ inputs or^ out-
puts? Digital inputs^ could be^ used
for alarm contact closures^ or^ similar, so you are emailed on^ your^ mobile to
say your house is^ being burgled,^ or
the bore pump^ in^ the back^ paddock has run out of^ fuel.^ [Yes I^ would^ need a long-haul WiFii LAN like^ I^ have^ now with an IP web cam on it (^) - all solar powered, of course).
Ifyou are running^ out^ ofcode^ space
you could offer an^ extended version
with the dsPIC33FJ12BGPB02 (ie,^ the
12BK version). What if^ you tossed^ in abit^ of code^ to talk to Dallas/Maxim 1-wire^ parts^ on
one of the digital pins? Then you^ could
have several DS1Bb20 temperature
sensors and ahumidity sensor^ as^ well.
One more pin^ for^ the^ anemometer
reed switch, one for^ the^ tipping bucket
rain gauge and an^ analog^ pin^ for^ the
wind direction pot^ and bingo you've
got a logging IP weather station^ in^ a WIB. The mind boggles at^ what^ could^ be
done and the variations of^ the^ "WIB"
dor,r¡n the track. Thanks^ for^ al^ excel- Ient project. Ray Hudson, Mareeba, Qld.
More praise for the WIB I just wanted to congratulate^ you on Mauro Grassi's fabulous Web-Server- In-,-Box (WIB)^ project. I^ am^ a^ hack experimenter who has^ recently^ started
trying to get^ my^ head around^ web- enabling my own^ amateut^ projects.
I am more interested^ in^ adding^ Tel-
net-style interfaces^ and^ email-enabling my applications than I^ am^ in^ creating embedded web^ servers.^ Do^ you^ plan^ on
releasing your^ source^ code^ to^ people
who buy/build these^ kits?^ I'd^ love^ to
be able to learn from your project and adapt the^ source code^ to suit^ my own projects, I know the Microchip^ TCP/IP stack is available on the internet^ but^ I^ am especially interested^ in^ learning^ from
your SMTP, Dlmamic^ DNS and^ FAT/
SD code. Anyway,^ keep^ up^ the^ good
work! Malcolm Macleod,
Brunswick West,^ Vic.
Glarification on DAB+ transmissions I would like to comment on some^ of tlre assertions made^ by^ Simon Kareh, in the Mailbag pages^ of^ the^ October 2009 issue, The best^ way to^ feed^ the transmitters is to^ encode^ the^ signal in AAC+ at the studio output.^ This
compression system is^ around^ twice
as efficient as MP3 hence needs^ about half the bit rate^ for the^ same^ quality
sound. No audio modifications^ have
to be made at^ the transmitter. The ABC^ is^ actually^ transmitting
some dynamic range on local^ radio
which has not happened before.^ ,td-
ditionally, they are^ transmitting^ Local Radio and Radio^ National^ in^ stereo
which has not^ happened since^ AM
stereo was switched^ off^ many^ years
ago. The technical specifications match those he^ quotes. The comments made^ aboutthe demo in Martin Place needs^ qualification. Firstly, this is^ the^ worst^ place for^ radio reception due to the^ buildings,
The main FM stations are 150kW
(ERP) (^) each and DAB+ in mainland
capitals are 50kW per^ transmitter,
provided they are^ transmitting^ at^ their
Letters and emails should contain complete name, address and^ dayt¡me^ phone^ number. Letters^ to the Editor are submitted on the condition that Silicon Chip Publicatìons^ Pty Ltd may edit and has^ the right to reproduce^ in^ electronic form and communicate^ these^ letters.^ This also applies to submissions to "Ask SILICON CHIP" and "Circu¡t NotebooK'.
Safe disposal of m¡Growave ovens
My microwave oven was^ losing
power and as it was fairly^ old I deemed its working life^ over^ and took it to the local recycling centre. Before I did, I removed the turntable drive motor for some future project. I knew that microwave ovens could
pack a lethal punch so re-read^ an
earlier Su,IcoN CHrp article (Decem-
ber 2006) before I did so.
At the recycling centre I cheerful- Iy asked what their procedures were when dismantling microwaves. To my surprise I had an^ immediate
audience. They are dangerous to
dismantle? No procedures existed.
The supervisor strolled over, a
perfectly reasonable youlg lady, and said she had dismantled hundreds
of microwaves without any special
precautions and had never^ had^ a
shock. I said that if she had, she might not be telling me this. I gave her a copy of your article.
She said that getting instructions
for dismantling any of the cast-off
detritus of ourmodern lives was next to impossible. Particularly bad was the dismantling of flat-panel screens without breaking the fluorescent
Iamps. Some of the staff are intel-
Iectually handicapped who are given employment by the local council so their understanding may not be high. Her situation, she maintained, was
typical of all the recycling facilities
inNZ. This is hardly an encouraging
picture. Surely the manufacturer or
distributor of consumer goods^ has
a responsibility for their final^ and
safe disposal? If this requires legislation and
incurs a levy at the point of sale,
tlat's fine witl me. This will ensrüe correct disposal procedures and^ it might just slow tlre rate of obsoles- cence of our consumer goods^ (might cheer your Serviceman up a bit too).
Any comment from the Austral-
ian end?
Andrew Buchanan,
Wellington, NZ.
Comment: sadly,therc are notmany
such recycling centres in Australia.
Stuco¡'¡ Cntp s¡l¡conchip.com.au
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Mailbag: continued
Glimate change is caused by man
The publication of Professor Ian
Plimer's letter does nothelp rational debate on the climate change issue.
The established method on which
we base our scientific knowledge re- quires verifiable, replicable, experi- mental evidence^ usually^ presented in (^) refereed scientific journals.^ The
fact that Mr Plimer has chosen to
use a his book, media interviews and Ietters to magazines such as SucoN Cmp (notknown^ for its^ environmen- tal science expertisel^ to^ publicise his ideas (without prior^ journal^ papers)
is a clear indication that scientific
journals and their referees have re- jected his ideas. The science journal ald peer^ referee system sometimes
fails but not^ often. The^ weight^ of
evidence for^ man-induced^ climate
change is^ overwhelming. Mr Plimer's comment about the whole thingbeing causedby "young
scientists seeking promotion"^ is
just plain stupid. He talks vaguely
of "cycles^ in^ climate"^ but^ fails^ to
explain why^ we^ are^ seeing^ changes
which have no precedent in size or
rapidity in a million years of geologi-
cal history.
There are now many thousalds
of pieces^ of^ evidence, collected^ by thousands of scientists in widely varying fields, which point to rapid climate chalges in^ the last^ century^ or two. Changes as^ rapid^ as^ those^ we^ are observing now^ have^ only happened in the past^ when^ there^ have^ been
cataclysmic events^ - asteroid^ impact
or major^ volcalic^ events^ - and^ it^ has
been many millions of years since
any such events. The scientific evidence for cli-
the DAB+ transmitter channels.
Since there are^ many reflections^ in
Martin Place and^ no^ direct^ signals, FM will have added^ distortion^ and^ if
you could hear it in stereo, the width
of the sound^ image^ wouldbe^ varying, depending on exact location. DAB+ is either perfect^ or^ non-existent. The antennas on^ all^ the^ DAB+ trans-
mitters are all vertically^ polarised,^ as
mate change has been published^ in
refereed scientific journals^ and^ (be- lieve me!) it HAS been disputed^ and argued (^) - at length (^) - but^ the^ case^ has held up under dispute and^ most^ of^ it is now accepted by the vast^ majority of scientists in both climate related and other fields,
If this was just^ another scientific
dispute, the public^ could probably
ignore it but this one^ will^ affect
everyone in the world in^ a^ big^ way.
Australia will be hard hit^ because^ we
happen to be in the wrong place^ on
the globe. I am an agricultural con-
sultalt with 40 years^ experience and
I have seen changes in^ the climate
of southern Australia over my time which are exactly in line with^ the climate model predictions. Our science is^ telling us^ that there is just^ a small chance^ that we
(and the rest of the world) can do
something about the problem^ and
can reverse some of the effects.^ But action will hurt and wiII^ require political fortitude and^ it^ takes vot- ers to put spine into^ politicians. Sucots CHIP readers^ are^ technically competentvoters who are^ capable^ of assessing data if they take the^ trouble
to do so. So I sought a^ single piece
of evidence which^ might^ convince
readers to seek more^ information^ on this matter. I chose this graph of CO2^ levels measured in ancient ice^ sheets (Fig,r). (^) It shows that CO2 levels have been cycling between^180 and
280 ppm for nearly^ a^ million^ years.
You can see the^ effects^ of^ several
of Professor Plimer's "geological cycles" there. The larger^ amplitude
90,000-year cycles correspond^ to
ice ages. The small^ (<10,000^ year)
he discovered. He may^ have^ got^ the
same result when the^ radio^ was^ upside
down if it was lifted^ so^ that the centre
of the antenna was^ in^ exactly the^ same place as it was^ the^ right^ way round.
This is only an^ issue^ in^ a^ situation^ like
Martin Place.
Since DAB+ is using COFDM^ modu- lation, you can have Single^ Frequency
Networks. These are^ already^ being
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Atmospheric G02 Concentrations From lce Cores 0ver The Past 650,000 Years
Fig.1: carbon dioxide concentrations from the Vostok, Dome C, Taylor Dome & Law Dome ice core in Antarctica and from the Cape Grim station in Tasmania. The (^) current global concentrations of carbon dioxide in the atmosphere (approximately^380 parts per million) are the highest in the last 650,000 years.
fluctuations are shorter warm-cool cycles affecting smalÌer sections of the planet (^) - some can be attributed to volcanic events. But there are no natural processes to explain why,
some 300 years ago, both a S0,
year steady cooling cycle and a
10,000-year cooling cycle were sud- denly interrupted and in just^300 years, the CO2 levels have shotup to
an unprecedented 4ooppm - ald the
rise shows no indication of slowing! It just^ so happens that at the same time (geologically^ speaking) as this rapid rise in "emissions", the
area ofland under forest decreased
dramatically (replaced^ largely by
methane-emitting rice paddies and
methane and CO2 emitting cows),
human populations went from half
a milÌion world wide to six billion
used for Digital TV in Kings Cross,
Manly East & Bouddi (NSW). Obvi-
ously these sites need SFN repeaters.
You will note that there are only three
DAB+ transmitters in Sydney at the moment for all those program streams.
They alÌ fit in a TMHz TV channeÌ.
So these repeaters can ofa
single Digital TV transmitter on each site. The Melbourne CBD, Dandenong
now and industry went fiom a few
horses to a system powered by multi-
gigawatt power supplies. Denying this sort of "coincidence"
Denial of "climate change" as a mankind-induced reality is a
denial of the foundation on which
our whole science and technology is based. Ifyou have a concern for your
childrens' welfare then go look at
whatthe fuss is about. Lookinw.vvw. ipcc.ch for the science reports and references to the hard science. Try www.climatechange.gov,au for the
Aussie view-point and some more
popular science explanations.
CliffHignett, BSc. App, CPSS,
Daw Park, SA.
Ranges and the south-eastern corner
of Port Phillip Bay require similar repeaters. As far as mobile reception goes, he
should try the "Pure Highway" which
is currently the only car radio, particu- larly if you add the magnetic antenna, True car radios are coming. Mr Kareh's antenna instaÌlation for DTV is suffering lrom impulse noise.
Sample price: USD43 78 plus S&H
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siliconchip.com.au DECEMBER 2OO
Dimmers (one^ with the IR RC option)
and they have served me well and look
decorative as well. Now as I read in
the Sunday papers the government has
decreed that I must use CFLs instead
of incandescent lamps, so would you
be willing to suggest how I can do so?
I do not need the dimming function. I need to switch the lights on or off so can the circuit be modifled to work on
CFL or will you be perhaps producing
a 2-wire CFL touch switch project with
IR RC option some time in the future? Guy Pearse,
via email.
Comment: (^) for the time being, you can still buy incandescent lamps
from lighting^ shops, some^ hardwarc
stores, some IGA supermarkets and
bargain shops. We suggest you stock
up because when present stocks run out, that we wílL be the end. AIso, it is still possible to buy 240VAC haÌ.ogen incandescents and
we also understand that you can still
buy lamps (^) for refrigerutors, ovens and microwave ovens. You should buy a stock of any that you might need (^) for
the life of your appliances.
Finally, some CFLs are dimmable so
if they are suitable for your particular
light fittings, you should buy some.
Energy sau¡ng stfateg¡es may not wofk Are people really serious about
energy saving and trying to save the
world? I have noticed that you (^) can
Active filter with
2-pole sect¡ons I just (^) purchased a kit for your Multi-Function (^) Active Filter proj ect (SrucoN Crur, (^) fuly 2009), for a meas-
urement appÌication. I identify the
fiIter circuits (^) as 4-pole low-pass and
high-pass, using series-connected
2-pole (^) sections. I (^) notice that the instructions for
setting up the filters suggest mak-
ing the (^) filter sections identical,
ie, both 2-pole sections using the
same components. Unfortunately
this doesn't quite work, since the
resulting compound filter will not have (^) the same cut-off frequency as the (^) selected value for the sections. I (^) understand that such an article is
not the place to rave on about the
placement of poles in s-space, etc
but I still think it should have been
pointed (^) out. I also notice that the latest version of the TI Filter Pro software now
covers lots of different fiÌters, not
only LP and HP. It also correctly cal-
buy master/slave power boards which
contain (^) a sensor that monitors the current running through the "master"
outlet ald automatically switches four
"slave" (^) outlets on or offbased on the status of the master.
I assume the idea is that you would
connect your (^) receiver/amplifier to
the master socket ald use its state to
culates the values for a 4-pole filter
consisting of two 2-pole sections, as
in this project.
]ohn Yelland, Milang, SA. Comment: two cascaded op amp active (^) filters with the szme com-
ponents will have the same cutoff
frequency. What^ does^ change^ is^ the
roll-off response. We did point out
that two cascaded Butterworth filters
will give what is called a Linkwitz-
Riley response. So two filters that
have a Q of 0.7071 will combine (^) for a (^) Q of 0.5. This is sometimes called a "^ Butterworth- s quare d "^ re spons e. With the TI Filter Pro, the 4-pole
response can be implemented by
setting up a custom (^) frequency and Q and^ setting^ the^ Q at^ 0.7071^ for each section. The rcsult is a Q of O.S
but the cut-off frequency remains
the same. We do know that Filter Pro covers
more types of filters than LP and
HP but we only concentrated onthe
types relevant to our project.
switch on peripheral devices such as a CD player, MP3 player, etc. Instead of many devices drawing standby power, only one device is actually
on standby while the others are ef-
fectively "switched off" at the socket. It seems a good ideabut the problem I have observed is that the "smart" power board uses more power than the
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Mailbag: continued
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Home-made booster for 3G signals
I noticed a request on page 106^ in
Ask SIucoN Crm, November 2009
(from M. P. via email) "wondering
if you guys have been able to come
up with a home-made signal booster
frepeater) for^ use^ in^ homes^ that^ do
not have the best 3G coverage", My daughter had this problem at her house near Beenleigh aokm south of Brisbane where, due to terrain shielding, reception on a Bigpond MAXON Model BP3-EXT 3G modem was marginal at best. 3G was their only alternative to dial-up
Rather than an active booster, I
made a¡r "external" antenna which
could be sat on a desk near a win-
dow facing towards the edge of the hill which blocked the radio path.
To minimise size, I used a bi-quad
design cut for B5OMHz. This feeds
the primary SMA antenna socket of
the modem via 4m of RGSBU cable. Gain is about 11d8, The improvement was spec- tacular. Performance went from
slow with frequent dropouts to top
speed with consistently high signal
strength indication. With a 353 x 90mm footprint and being just 353mm high, it is small enough to sit unobtrusively at the back of the computer desk, looking happily out the window.
Material for the backplane might
be a problem for some constructors.
I just happened to have a piece of
staldby state of^ the connected devices. On one occasion,^ I^ have^ measured [using a^ simple^ Jaycar energy meter) over 10 watts^ when^ the^ powerboard^ is connected witlout arything plugged in. The amplifler and^ CD^ player com- bined use less than this amount^ when connected on standby.
This seems to be^ a^ crazy^ situation
when you^ need to^ use^ more^ energy^ to "save" a small amount. At the Secondary College^ where I teach electronics and physics,^ the "experts" (^) have recently told us we waste too much power^ on^ lighting,^ so
1.Bmm aluminium sheet recovered
fiom some computer equipmentbut any sort of sheetmetalwould sufÊce.
The backplane is 353 x 353mm with
BBmm flanges bent forward at right
angles at^ the^ top^ and^ bottom^ to^ form^ a
shallow U-shape,^ ie, the^ bla¡k^ size^ is
532 x 353mm, allowing forbending. The antenna^ is^ bent^ from^ a^ length of 2.1mm diameter copper^ wire with quad sides B6.1mm long and
it is mounted 44mm^ in^ front^ of the
backplane using apiece^ ofhard plas-
tic tube. The^ coax^ shield^ and^ inner
conductor are soldered^ directly^ to
the biquad feed^ points^ and^ the cable
run back through^ the^ mounting^ tube. The altenna wire^ was^ formed^ by bending it around two^ 2-inch^ nails
(outside spacing B4mm) driven into
a piece of timber. Marc Fraser,
Camp Hill,^ Qld.
timer switches have been^ installed^ in
every classroom. These have been^ set
to turn the lights^ off, usually^ within
fi.ve minutes of^ the end of^ each^ lesson. If the lights go out before the^ lesson
flnishes, we turn them back^ on^ and
they might stay on 40 minutes^ into
the next lesson, even^ though^ the^ room might be empty. I think educating people^ to^ turn Iights off when they leave^ or^ even us-
ing proximity switches would^ have
been a better solution.
But there's more! The existing^ wir-
ing in most classrooms previously^ al-
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72 StLtco¡rt Cøtp siliconchip.com.au
When the Tokai Challenger, overo.ll^ winner^ of^ the^ 2oÙg^ Globql^ Green
Chøllenge (aka^ Wofld^ Solar^ Challenge)^ finished nearly^ a^ full (^) _day' ahes.d ol the (^) field, AustralÍa's Sunswìft^ IVy^ was back^ in^ f_ourth place...
and the-teqm T*^ the UnÌversÍty of^ NSW^ couldn't have^ been^ happÍer!
lTlhe (^) fapanese team^ crossed the I control finish line^ just^ north^ ol I Adelaide at 3,39pm (CDST) on
28 October after^ a^ near-faultless^ run
from the start^ in Darwin.^ With^ a^ maxi- mum vehicle^ speed of some^ 150km/h and an^ average^ just^ over tOOkm/h^ for
the journey,^ their only incident was
a flat tyre which the support team changed almost^ as^ fast^ as^ a^ Formula 1 on race day! Total elapsed run-time was a miserly 29 hours and 49 minutes.
The win by Tokai Challenger broke
the four-race winning record of the
Nuna V^ team^ from^ the^ Netherlands.
It finished in^ second place,^ at^ B,3OAM
next morning,^ with^ the^ Infinium^ team
fromthe University^ of^ Michigan^ (USA) crossing the^ line^ at^ 9AM.
Then in fourth place was the first of
the Aussie teams,^ tle^ Sunswift IVy,^ at
L4 Stuco¡rr Cmp
3.08pm. Fifth^ was another^ American
team, "Eleanor"^ from^ the^ MIT,^ and
sixthplace, at9,10amnext day,^ was^ the Aurora 101 from the^ Melbourne-based ,\urora Vehicle Association, ,\ lot of pre-race^ hype had the^ Brit-
ish expecting to^ do^ very^ well in their
Cambridge University^ "Endeavour"
but unfortunately they^ came^ in^ 14th
place, having covered only^ 1616km^ of
the 302fkm course.
However, they^ fared^ much^ better
than the Swiss team's^ "Swisspirit",
which didn't^ even make^ the start and
the Canadian's "Eclipse"^ which^ trav-
elled less than 100km. Another^ team
expected to do very^ well^ but^ withdrew
after only 380km was^ the^ Belgian team's "Umicar Inspire".
Sunswift IVy Having attended the^ Sunswift
IVy press launch at^ Dee^ Why^ beach
a couple of weeks before the^ race
commencement on October 25,^ we
followed the team's progress^ with
interest, via live updates on^ the web.
That site was fortunate because^ the mainstream media focussed^ almost en-
tirely on the first three placed^ vehicles
after the Belgians withdrew,^ virtually
ignoring the Australian contingent. The total IVy project^ cost^ was esti- mated to be (^) $28o,ooo (^) - a^ signiflcant proportion of which^ was^ in^ solar^ cells
- but^ if^ the amount^ of ftee^ time^ given by UNSW student and faculty^ was factored in the cost would^ likely^ be
several orders of magnitude^ greater.
Total project time was^18 months. The IVy (so^ calledbecause itwas^ the
fourth UNSW solar "car"^ to bear the
name) actually came first in^ its^ class,
those with silicon-based sola¡^ cells.
vvww. s i I i c o n c h^ ip. co^ m.^ a^ u
The racers whichfinished above^ ithad
state-of-the-art cells^ which^ offered^ up to 30% effrciency^ (versus^ IYy's^ 22%). Incidentally, Tokai Challenger's^ so-
lar cells were made of rare metals with
an output of 1.BkW These^ cells^ are
usually used for powering^ satellites. This year,^ the rules were^ changed
somewhat including^ a^ maximum^ of
6 square metres^ of^ solar cells^ - IVy packed in 5.998 square metres! The Tokai's 2'1.76 soh cells, supplied^ by
Sharp Japan, measured 77 x^ 39mm.
Another change was that^ tlre^ driver
had to maintain a^ seated^ position^ (in
the past,^ most were recumbent).
Sharing the knowledge While the entrants in^ the^ World
Solar Challenge are deadly^ serious
about winning and use^ every^ trick
in the book to try to gain a miniscule
vLlww. s i I i co n c h ip.^ co m. a u
advantage for their vehicle, one ofthe
features of the race is the camaraderie between teams and the sharing of
knowledge and technical develop-
ments.
Indeed, on the Sunswift website,
the team have placed a considerable amount of their computer software
and hardware, with a piomise of more
to come, for other/new teams to use.
Different divisions The Global Green Challenge com-
prises two categories, with more than
one division in each catering for clif- ferent types of vehicle and/or teams: The World Solar Challenge (^) - for
purely solar-powered vehicles (and
there are different divisions in that) open to teams lrom universities, tech- nical institutes, private entrepreneurs and past participants, and
The Eco Challenge (^) - open to^ all
manufactures and producers of low
emission, diesel, hybrid, electric, hydrogen and alternative fuel supply vehicles.
There were many "factorY"^ teams
entered in the Eco Challenge but^ one
outstanding entrant, in^ the^ Produc- tion Class 2-Seat Electric^ Vehicle,
was a Tesla Roadster (the^ only one^ in
Australial, driven by Simon Hackett,
owner of Internode (an^ ISP). On the fourth day of the^ race,
Hackett set a world distance record^ of
501Lru (313^ urilesl on a^ single^ charge
of the Tesla's lithium-ionbattery pack.
References:
www.sunswift.com./ivy www./www. internode. on.net /news/ 2009n0í.55.php (^) 9C
by ROSS TESTER
DECEMBER 2OO9 15
Taken from a large coil of wire around the Pest Free, (^) this is the signal radiated by the unit when the blue LED is flashing. This scope grab is taken at a sweep speed of 5Oms/div (quite^ slow).
www. s i I i con ch i p.^ co m. au
This (^) is the same signal radiated by the Pest Free but taken at a
sweep speed of sOOms/div (very^ slow - it takes 10 seconds for
the trace to sweep across the screen).
NOT mean the NSW Office of Energy has checked the claims or even checked
to see if it works - it simply means it's
passed safety checks. (We agree: it is well made). But you have to get approval for toasters and 3-pin plugs too!
Since there is a cÌaim that the Pest
Free modifies the magnetic field in your home, we decided to see if we could measure that. To do so, we rigged up a loop of 4-wire alarm cable around our large office. The four wires were con-
nected in series so that we effectively
had a 4-turn coil around the room. This was connected to al oscilloscope and we then monitored the voltage induced
into that coil by the magnetic fields in
the room, The results are shown in the ac- companying oscilloscope screen grabs.
These show the fleld with and without
the Pest Free active, ie, when its LED was flashing and not. As you can see,
::i::' Agllg¡t^ Tsdrmlogis¡
Hmmmm. It "modulates the existing electro magnetic field of your^ wiring. University tested
vlr, *" found a tiny spike on the
mains wiring
(see (^) scope grabs) but we got a larger spike from fluorescent lights, computers, etc.
the measured inducedvoltages are quite
low and mainly consist of pulse noise
coincident with the zero-voltage cross- ings of the 50Hz mains sinewave. This pulse noise would no doubt be caused by all the switchmode power supplies in our office in computers, printers and so on. Some of it would undoubtedly also come from the fluorescent lighting in our building. Anyway, we were able to see the effect on the induced voltage waveform when Pest Free was active. Each time the blue
LED flashed, there was a coincident
impulse superimposed on the waveform every 640 miÌliseconds, ie, about five
pulses in tlree seconds, But does this
R SEP'18 16:0912 2mg :ü. Asllsf^ Tscùnologis¡
amountto amajor disruption of^ the am- bient magnetic field? Clearly, the effect is extremely slight, Either^ cockroaches, rats and mice are extremely sensitive to electromagnetic fields (^) funlikely) or^ Pest FreeII doesn't work. We should also note that the act of turning on all the fluorescent lights
in tlre office generated a much^ bigger
"disruption of electromagnetic flelds"
than Pest FreeII. That is^ what you^ would expect, since each fluorescent light fit-
ting has a substantial electromagnet in
the form ofthe ballast inductor. We seriously doubt whether mice, rats or cockroaches are affected in anyway
by the modest electromagnetic flelds
FH SEP 18 16:10:30 2009
"Approval No CS6455N"? That does
Pe3î^Free'II
Pest Free simply plugs into any house hold power point.^ When switched (^) on it
modulates the existing electro
nragnetic field of your w¡ring. University
tested for mice and rats. Testimonials from Australia and overseas confirrr Pest
Free affected the normal behaviour of
mice, (^) rats and cockroaches.
',r; ,c.r';sI0^ hazardous (^) chpmi
DECEMBER 2OO9 17
in household wiring, electrical appli-
ances or any other electrical equip- ment (^) - otherwise you would think
they wouldn't infest anybuilding with
eiectrical wiring, In fact, as far as we can teÌÌ after searching for information on the sub-
ject, there is no evidence that cock-
roaches are affected by magnetic fields in any way. Interestingly, cockroaches are sensi- tive to high voltage electrostatic fieÌds and they will avoid such fields, Their
antennae detect the fields. If their an-
tennae are cut off, they are in no way
affected. Mind you, if you stand within
a very high voltage electrostatic field,
.i::: AgilentTsctrclogiss
Pretty blue LED: every time it flashed (at about 640ms rate) a very short duration impulse appears on the mains. We wonder what is so special about this rate (^) - and if this was the "proven frequency" which repelled mice, rats and cockies, Proven by whom?
your hair will stand on end. You will probably find this unpleasant, just like cock- roaches apparently do! If you want evidence that cockroaches are not affected by magnetic fields, you only have to consider their be-
haviour inside the cases of
microwave ovens,^ ie, inside the (^) case, not inside the oven itself. When a microwave oven is on, both its large transformer and the magnetron
will generate significant magnetic fields
but there is no evidence that^ the cock- ies make any effort to^ decamp^ - they love the warmth^ generated^ by the^ fact that a microwave is^ always^ on^ standby and they are probably^ attracted^ by^ the
grease and food deposits inside the
cabinet. As our Serviceman often tells, many a microwave oven has^ been disabled^ by cockroaches inside^ the cabinet^ but un- less they have the misfortune to come into (^) contact with high voltages they are not harmed at all. What about the
FBI OCT 16 13:52:57 2009
fields on rats and mice? Again, we
could find no evidence along these lines. In fact, some years ago NASA appar- entÌy did some experiments on levitat- ing mice in the intense fields generated by superconducting magnets but after a short period of exposure, the mice car- ried on as if everything was normal. We
wonder if they liked levitatingl
Finally, we measured the power
consumption of the device. The fact
that it gets warm indicates that it uses
significant power, perhaps as much
as 10 watts continuously. In fact, we
measured the power consumption at close to 7 watts, the figure claimed by the manufacturer. fust so^ you know, since^ it^ is^ intended
to be on all the time, over a year that
will cost you (^) $9.57, based on Sydney's Energy,A.ustralia domestic electricity
tariff of 15.6 cents/kilowatt-hour. You
might think that just under ten dollars per annum is a low price to pay to be free of cockroaches, rats & mice. It would be (^) - if it worked. Based on what it appears to do (^) [or not do), we have serious doubts.
Internal examination
Having pussy-footed around with
the "bÌack box" approach, we decided to take a more investigative approach,
by breaking the thing open! We duly
squeezed it judiciously in a vice until
it cracked (^) - the case, that is. We were
then abÌe to bare it to the world. And
This scope grab shows the background low frequency
electromagnetic signal from a large inductive loop in
our office, The groups of spikes at^ 10ms^ intervals^ are switching hash from computer power supplies.
18 Sil,tcotrt Catp
this is what it contains.
effect of magnetic^ At^ one end^ it^ has a^ coil^ wound^ on
::::: Agil8rtTecùnologisE FBI^ ocf^16 I^ 4:41:3'l^2009
The same background signal but with the added spikes^ from^ the Pest Free device at intervals ofabout 640ms, The Pest Free^ spikes are still relatively low in amplitude and quite^ small compared to those produced when switching on the office lights,
w vLlw. s i I i co n c h i p.^ c o m.^ a u
