8 Silicon chip Australia’s electronics magazine siliconchip.com.au
It is a total nightmare trying to get anything out of these
people. You can only chat with them online via their web-
site, but I find the interface very awkward to use. I have
spent some three hours over a month and have gotten no-
where with them. I requested they email me so we could
communicate properly, but they refused.
I’ve had occasional problems with Amazon and PayPal
before, but I was always able to pick up the phone and
talk to someone for a satisfactory resolution. So, I won’t
be buying on AliExpress in future.
Ron Cooper,
Collaroy, NSW.
Response: we have had mostly good luck with AliExpress,
but as you say, when things do go wrong, it can be a real
nightmare. There have been a few times that we have re-
ceived counterfeit, defective or incorrect goods and have
been unable to get a refund. In some cases, we have got-
ten a partial refund, but that hardly seems fair when we
did not receive the items that we ordered.
But it’s a bit difficult to recommend that readers avoid
the site for these reasons because they have a great range
of products at very low prices and even if you allow for
say 5% of your purchases to ‘go wrong’, you’re still get-
ting a pretty good deal overall.
Having said that, it’s still very frustrating when their dis-
pute resolution process finds in favour of shonky sellers.
You need to keep in mind the usual slogan when it comes
to purchasing goods: “caveat emptor” – buyer beware!Solar bilge pump ‘gotcha’
I thought your answer in Ask Silicon chip, March 2019
(page 102) about matching a solar panel to a bilge pump
was good, but there is ‘gotcha’ which never shows up in
testing.
Imagine that the float switch closes in the night. The sun
rises exceptionally slowly, and there is no ‘kick’ or switch-
on impulse for the motor. When the panel is well illumi-
nated, the panel short circuit current continues flowing
through the same commutator segments, but the armature
never rotates. It could burn the motor out.
The Alternative Technology Association used to sell a
kit for this particular application which is now available
from LEDsales (siliconchip.com.au/link/aapu).
You can see the circuit on that website, with a good ex-
planation of how it operates. It is called a “Solar pump-
ing maximiser”. They have kits for various pump currents
in 12V and 24V versions. I have no connection with the
vendor other than as a satisfied customer.
Finally, Brendan Akhurst deserves a pay rise. He is on
my wavelength, and I have enjoyed the banter about Joe
Lucas – Poms learned to drink their beer warm because
Lucas made the fridges!
Richard Elliott,
Majors Creek, NSW.The times, they are a-changin’
Regarding your April editorial, as a lad, I attended a
school in the 1950s. Every second Tuesday had a session
of Army Cadets or Community Service. My Community
Service group was one which took in “trade in” radios
from retailers, refurbished them (mainly by replacing the
electros) before they were distributed to pensioners who
couldn’t afford one.In my case, I was messing about with old black & white
TVs, playing with the HT and zapping my brother or the
plants in the garden, much to my parents’ dismay.
I have been involved in electronics for over 40 years
now and have seen the changes in the standards to which
goods are manufactured. Some poorly made and, in my
opinion, dangerous equipment has come in from overseas.
This equipment somehow makes its way onto our shores
and ends up installed into peoples’ homes, just waiting
for some unsuspecting person to be killed due to the rel-
evant government body not doing its job and halting the
import of this junk.
The articles and projects published in Silicon chip and
its predecessors (EA, ETI, AEM etc) have always been well
thought-out with regards to electrical safety.
What is of even more concern is the lack of backup for
000 emergency calls with the NBN roll-out. It’s typical
government stupidity; I am sure there will be many more
deaths from people not being able to call the fire brigade,
police or ambulances in emergencies.
Anon.
Some sellers on AliExpress are unscrupulous
There is no magazine in the world like Silicon chip.
Keep up your great work. I notice that you occasionally
refer readers to products sold via AliExpress. I have been
buying bits and pieces from AliExpress for about 12 months
with no problems. But in January I was sent goods not as
I requested. On checking my credit card statement after
they arrived, I found a second charge of a similar amount
taken by them on the same day but with no reference.
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