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SILICON
SILIC
CHIP
www.siliconchip.com.au
Editor Emeritus
Leo Simpson, B.Bus., FAICD
Publisher/Editor
Nicholas Vinen
Technical Editor
John Clarke, B.E.(Elec.)
Technical Staff
Jim Rowe, B.A., B.Sc
Bao Smith, B.Sc
Tim Blythman, B.E., B.Sc
Technical Contributor
Duraid Madina, B.Sc, M.Sc, PhD
Art Director & Production Manager
Ross Tester
Reader Services
Ann Morris
Advertising Enquiries
Glyn Smith
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glyn<at>siliconchip.com.au
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David Maddison B.App.Sc. (Hons 1),
PhD, Grad.Dip.Entr.Innov.
Geoff Graham
Associate Professor Graham Parslow
Ian Batty M.Ed.
Cartoonist
Brendan Akhurst
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Editorial Viewpoint
Beware of dodgy and counterfeit
electronics
It’s bad enough that we are bombarded with so many
scam e-mails, phone calls and letters these days. But
you also need to be on the lookout for dodgy products.
Sometimes we order products from suppliers that
we haven’t dealt with before, either because we can’t
find them elsewhere or when there are delivery delays
with our usual suppliers, only to receive either counterfeits or poorly-designed clones. Often, we pay the
same for these dodgy parts as we would for the genuine articles.
For example, we purchased some batches of 74HC595 logic chips for our
LED Christmas Tree kits (which were resoundingly popular). We ordered
batches from different suppliers in case some of them were delayed, as we
needed to get them in customers’ hands well before Christmas, giving them
time to build the trees.
Many of the chips we received were fine. But a couple of batches were
faulty. And I don’t just mean one or two chips; out of hundreds of chips,
none of them worked. The dud chips came from at least two different suppliers but they all had the same date code etched in the top, along with a
Texas Instruments logo. That certainly doesn’t guarantee they were actually
made by TI, though!
Their quality assurance (QA) process would have picked up a failed batch
of chips and they would have been discarded. So either these chips were
pilfered from the rubbish tip and sold to us, or they were counterfeits, brazenly etched with the TI logo.
Why someone would bother producing fake chips that are so cheap is a
mystery to me.
Luckily, after complaints from customers over the first batch, we wised up
and tested all the chips we received. And we were able to replace most of
the first batch before they had been used. But it was still a huge hassle and
we didn’t get our money back from all the suppliers either.
So you really need to watch out for this sort of thing when you are buying
electronic components from online marketplaces. Stick with the big-name
suppliers where you can. You’ll get what you pay for and if you do have a
problem, you can ask for a refund.
You should also be aware that some of the “El Cheapo Modules” that we
write about suffer from shady practices. When a module becomes very popular, clones are produced in large quantities and they are sold as if they are
the genuine article. In many cases, the clones work fine but in others, they
have design flaws or are poorly made.
The CP2102-based USB/serial modules are a good example. Some of the
clones don’t seem to have genuine CP2102 chips on them, as there is no etching on the top of the package. They work but the “3V3” output voltage is not
correct, due to a PCB design flaw.
There are also plenty of clones of the popular BMP180 temperature/humidity module. Some have a mounting hole that’s way too large but otherwise seem to work OK.
It’s amazing what people will do to make a couple of dollars. You need to
be vigilant when ordering from online marketplaces to make sure that you
get what you pay for. Unfortunately, that’s the flip side of the coin of these
handy little electronics modules being so cheap.
And don’t get me started on the wildly optimistic mAh ratings of so many
18650 Li-ion cells, jumpstarter packs, and the impossibly high lumen ratings
of some high-powered LEDs...
Nicholas Vinen
Derby Street, Silverwater, NSW 2148.
2
Silicon Chip
Australia’s electronics magazine
siliconchip.com.au
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