Net Work
Alan Winstanley
This month’s column has a practical angle, looking at broadband router choices and advice
about choosing quality mains adaptors. Aspects of DC connectors and USB charging are
discussed, and there’s a new online shopping mall to try.
A
few weeks ago, my home
network went down late one
night without warning. The
outage brought my workflow grinding
to a halt, but it also reminded me
how Internet and network access had
become an essential utility in many
households. I delved under the desk to
check the simple things first: swapping
Ethernet cables around and jiggling
them in their Ethernet ports just to
make sure everything was secure, but
to no avail.
The weakest link
I then found that my multitude of smart
lights and sockets, streaming TV sets
and smart displays, speakers, Internet radios and security cameras had
packed in as well, along with Wi-Fi,
the home area network, and network
storage and shared drives. In total,
more than two dozen devices and
gadgets that needed network access
had all stopped working.
My ISP confirmed my broadband
supply to be in order, so everything
pointed to a problem with my router.
My trusty Billion 7800N dual WAN
router is over a dozen years old and
was designed for heavy SOHO use; it’s
powered up 24x7 and had never missed
a beat, thanks partly to its roomy,
well-ventilated plastic housing which
helps with cooling. However, this
model uses a separate BT Openreach
modem which is hooked to
the telephone socket. Both
the modem’s power and ‘DSL’
LEDs were glowing, proof
positive that the broadband
was up and running (like my
ISP said), but the modem’s
‘WAN’ LED was off, a sign The TP-Link TL-MR6400 is typical of the latest Wi-Fi
routers, and it has a SIM fail-over slot to carry a SIM
that the router itself wasn’t card backup. It needs a separate modem.
working for some reason.
I found that none of the router’s port along like this until I could source a
status LEDs were illuminated either quality mains adaptor, a topic that I
but, strangely, the router’s power LED cover shortly.
was flashing very faintly. Checking the
mains adaptor with a multimeter, the The route ahead
DC output measured 12V as expected, If a router replacement is on the cards,
so I guessed there must be an internal then it’s worth trying to buy one that’s
router fault. I dreaded the thought of as futureproof as possible. I was surprised by the limited choice of routers
having to source a new one with all
the set-up, disruption and configu- now available online – I guess most customers use the hubs provided by their
ration hassles that would go with it.
That flickering power LED had raised ISP, though working-from-home and
my suspicions though, so I fetched a the semiconductor shortage had poslaptop-style variable voltage PSU set sibly affected supplies too. There were
to +12V, and I jury-rigged a DC connec- a few menacing-looking routers made
tion to the router. I switched on to see by Netgear, D-Link and TP-Link, some
what would happen – and it worked! very expensive models from Draytek
The network burst into life again. The and a handful of low-cost ones from
router’s switched-mode mains adaptor the Chinese Tenda brand. Some Wi-Fi
was obviously the culprit – measur- routers only offered 2.4GHz, not 5GHz,
ing 12V no load, I found it had some which is an essential choice for the
future, so check those specs closely.
sort of internal fault that shunted
The latest routers offer Wi-Fi 6 and
the output when under load, which
would keep power-cycling the router dual or triple bands and many now
– hence the flickering power LED. For have built-in modems. A few have
a few days my entire network limped a SIM-card ‘fail-over’ slot for a SIM
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12
Practical Electronics | September | 2023
As every PE reader knows, mains
adaptors, wall warts, power bricks,
whatever you call them, are used by
most mains-powered low-voltage devices: there are nearly 20 adaptors near
my desk alone. Hot and heavy transformer-based PSUs have been replaced
by compact, lightweight switchedmode types, and consumer products
increasingly use a 5V USB-type mains
adaptor. So many USB chargers now
litter the planet that some makers now
omit mains adaptors from their
products altogether and consumers have to provide their own.
While sourcing a new mains
adaptor for my router, I found a
huge variety of unlabelled types
on all the usual websites. I avoid
cheap unbranded ones that have
no manufacturer’s details, as
these are untraceable back to their
source, they may be non-compliant
and any UKCA or CE marks can
be considered dubious. Shoddily made adaptors can snap apart
when you pull them out of a typical British mains socket, exposing
live wires inside. One relative
unplugs everything that is not in This Zolt-branded variable voltage mains
use, even the smart meter, when adapter has a DC and 5V USB connection kit
she is not at home. A fire officer and carries the assurance of UKCA markings.
told her how he attended several
house fires a week, all caused by overheating mains adaptors and chargers.
I finally chose a multi-voltage 34W
type branded ‘Zolt’ which offers 3V
through to 12V as well as 5V and a
USB A-type port, rated up to 2A. This
UKCA-labelled adaptor seems well
made and also has an LED pilot light
and comes with nine DC plug adaptors,
including some handy USB types. It’s
happily powering my router as I write, DC connectors with bifurcated contacts –
and the multi-voltage selector makes recognisable by the slotted centre – offer
it an ideal spare to keep in stock. It is the best electrical and mechanical contact.
hard-wired as centre (tip) positive. At
bifurcated contacts (recognisable with
the time of writing, it’s available on their slotted centres) provide the best
Amazon (B08L3HD4MR).
grip and electrical connection. ConfusObviously, a matching DC jack was ingly, they are sometimes specified as
also needed for the router and users having two inner diameters – one with
are left to puzzle over several dozen their spring contacts open (ie when
combinations and styles. I saw one slack, unsprung), and another when
100W ‘universal’ power brick sold on compressed tightly shut (in situ).
eBay had nearly 30 such DC adaptors
to fit a laptop, and readers doubtless More USB gadgetry...
have handfuls of those primitive two- Numerous USB-powered accessories
pronged DC plugs kicking around are now sold online through the usual
somewhere, though never in the size sources. A 5V supply for electronic gear
that you need. In my
case I counted at least
seven combinations
of the commonest 5.0
and 5.5mm (OD) ones,
with just fractions of a
millimetre to choose
between them. Until
they invent a DC connector measuring tool,
I often end up checking the outer diameter
with digital callipers.
Getting the correct
innermost conductor
size is more problematic: some plugs are a
wobbly fit, and finding
the most reliable size
takes some trial and Charging solar floodlights from a Ryobi 18V USB adaptor
error. DC plugs with and monitor, with a custom 5V lead and DC connector.
Practical Electronics | September | 2023
13
The UKCA conformance mark is starting
to appear on electronics sold in Great
Britain. The EU’s CE mark will be
superseded in Britain from 2025.
card data plan, a backup in case the
main broadband goes down: the spec
sheet will mention ‘4G/ LTE’ somewhere. One example is the TP-Link
TL-MR6400, which costs about £75,
though higher-spec models cater for
more demanding users. These routers
need a separate modem, but for some
reason stand-alone modems seem to
be thin on the ground. One of the very
few contenders is the Draytek Vigor
166, which costs £125 from the BT
Shop. It turns out that many legacy
BT Openreach VDSL modems (like
the one screwed underneath my desk)
were originally made by Huawei, and
the Huawei Echolife HG612 (‘3B’ version) is the most desirable one. I found
several used ones on eBay costing just
a few pounds – I’ve bid on one which
I’ll keep as a spare!
A whole-home mesh router is another option for upgraders, and major
brands each have their own mesh product ranges. Amazon now owns Eero,
the pioneer of whole-home mesh; TPLink sells Deco Wi-Fi mesh; Netgear
offers Orbi; D-Link’s mesh system is
called ‘Covr’; and Tenda sells Nova.
D-Link also offers Wi-Fi 6 routers that
are mesh-ready. My Mercusys (by TPLink) mesh system is adequate for now
though, and I was relieved to patch
up my network for the price of a £12
mains adaptor – a bargain!
Power mad
This USB digital voltmeter/ammeter
displays the status of the charging rate. It
logs data on ten channels.
can be derived from a USB A-type lead
terminated with a suitable DC adaptor plug – kits of these are available
online. I use one to charge up solar
floodlights from an 18V Ryobi USB
adaptor when overcast weather is preventing the solar cells from charging
in the daytime. This home-brew 18V
USB powerbank is kept in a marine battery box to withstand wintry weather.
Sometime, I’ll modify the Ryobi adaptor to add an LED power-on pilot light,
which is a strange omission, but for
now I use a USB LED pilot light on a
spare port (see photo) as a reminder.
Many readers own a 10-20,000mAh
USB powerbank to top up their mobile
phones or tablets. I’ve found alarming
differences in the build quality of USB
leads, especially when high-current,
fast-charging PD (power delivery) devices are used with them. Some USB
connectors become very warm during
rapid charging, so I tend to keep a wary
eye on powerbanks when in use. An
inline USB digital voltmeter/ammeter
(available online for a few pounds)
allows me to monitor the charging
current and capacity. They also have
ten memories, scrolled through using
a pushbutton. I gave a similar one to
the owner of a Samsung tablet which
had a slightly wobbly USB jack, so she
could tell if it was charging properly
when she ‘jiggled’ the plug!
Last, with the holiday season in
mind, here are some useful travel tips:
if ever readers find themselves needing to charge up their mobile phone
or tablet at a public USB outlet (eg,
at an airport, shopping mall or cafe),
The PortaPow Data Blocker has no data
pins and claims to prevent ‘juice jacking’ if
a public USB charging point is used. USB
A-type and C-type dongles are available.
14
then a clever USB pass-through adaptor is available that provides power
only, with the serial data pins omitted. This claims to overcome the risk
of so-called ‘juice jacking’, where a
hacked USB outlet might try to install malware over the USB data bus.
The PortaPow Data Blocker adaptor is
available from the usual online sources for about £7 each.
When out and about, readers will be
aware of the risks of using untrusted
wireless hotspots which may eavesdrop, hijack or try to install malware
through compromised websites: using
a VPN connection to surf the web,
check mail or use apps is the safest bet.
Tee Time
It’s a fact of life that cheap electronic
devices, novelties, gadgets and myriad
household items can now be sourced
from the Far East with little more than
a mouse click. Our series Low Cost
Electronic Modules exploits the availability of these cheap imported circuit
boards that aren’t worth the time or
effort to make at home. Most readers
probably buy online from websites such
as Alibaba, AliExpress or Banggood at
one time or another, with crumpled
little polybags from China dropping
through our mailboxes a few weeks
later (hopefully).
Some Amazon and eBay sellers are
highly geared towards the express
shipping of goods that arrive directly
from China just a few days later. The
practice of ‘drop shipping’ means
that some sellers don’t even carry
any stock, but simply forward customer orders to an order fulfilment
centre or to the manufacturers themselves. Many eBay sellers are based
overseas, and their online stores often
contain a wacky selection of items of
dubious value. Even so, eBay can be
a goldmine – the other day a critical
spare part for a Panasonic razor arrived
from a small Japanese store (complete with an origami gift), delivered
by DHL in just a few days – although
one must keep an eye on the risk of incurring UK import duty and VAT, see:
https://bit.ly/pe-sep23-tax
eBay also turned up trumps with
some silicone rubber O-rings needed
for my solar floodlight’s waterproof DC
connectors, which came from China
and were another welcome little ‘find’.
Lately, a new web-based e-commerce brand has arrived in the UK
that is gunning for a big slice of the
action. Already hugely popular in the
US, the Chinese sales platform Temu
(‘Tee-Moo’) has come from nowhere
and is setting out to rival Amazon and
AliExpress as a consumer-friendly
online bazaar that sells a huge range
of mostly unbranded little gadgets,
gifts, novelties and accessories of the
sort that you probably won’t mind
gambling on buying, in the hope that
things won’t go wrong. The Temu app
is currently the most downloaded
one from Apple’s store, and Temu’s
online advertising has reached saturation level: brand recognition is the
name of the game for now, and Temu
is carving its way relentlessly into the
market with crazy loss-leading prices
and free shipping.
Temu’s web pages remind me of those
wacky eBay stores hosted by Chinese
traders. Scrolling through them makes
you tired and plenty of dark-pattern
sales techniques are on show, such as
countdown timers, roulette wheel spinners and supposed discounts. Avoid
links or vouchers containing ‘aff’ (affiliate) codes, we’re told – these are
bogus attempts by others to cash in
on your business and won’t lead to
you enjoying better prices.
Many Temu shoppers will see it
as having a bit of fun, but early reviews on Trustpilot (see https://bit.
ly/pe-sep23-tp) from UK customers
are polarised: two thirds of reviewers
were delighted, or maybe they’re just
easily pleased, while one third were
very unhappy. One user commented
that Temu scrapes up huge amounts of
personal data while others complain
of being bombarded with notifications and marketing after signing up
with Temu, the pressure to buy being
incessant. You can sign up at temu.
com if you want to try those early discounts, though one reviewer cautions
buyers to ‘probably steer clear of some
electrical items’. That likely includes
unbranded mains adaptors.
It’s here... somewhere! Using smart
meters in isolated rural properties may be
impossible, so traditional meters will still
have to be read manually.
Practical Electronics | September | 2023
Down on the farm
Regular readers will recall my recent piece about shopping online for house insurance on behalf of an elderly
lady who lives in a remote farm. This week, your scribe
was down on the farm again, this time waist high in a field
of hay, in search of the farm’s electricity meters. It turned
out that meter readings were being submitted monthly
over the phone (there’s no Internet access, remember) but
errors that had accumulated over time meant the monthly bill was out of kilter and the owner was owed a very
substantial refund. I have nothing but praise for the electricity supplier, E-On, who went to great lengths to rectify
matters after I explained and submitted accurate readings
(and emailed them a photo of the meters just to be sure).
E-On helpfully suggested that I become an authorised user
for the lady’s account, allowing me to submit readings and
print off monthly invoices via the web, something that will
be a regular job from now on. Just to remind everyone of
the continuing need for cash, the lady then likes to journey to the local post office to pay the electricity bill (and
others) over the counter using proper money.
The cost of the UK’s bungled smart meter programme is
expected to reach £13bn or more, a sum equal to nearly
a quarter of the UK’s entire annual defence budget. The
farm would be an ideal application for a smart meter,
and one was in fact ordered last year. However, the visiting engineer took one look at the field and beat a hasty
retreat, claiming that fitting one was impossible. Furthermore, the farmhouse was too far away from the electricity
meters anyway, as the maximum recommended distance
between a smart meter and an In-Home Display is just
10m. The Data Communications Company (DCC) – the
name behind Britain’s smart meter rollout – boasts that
the [smart meter] network now ‘supports almost 25 million meters in 15 million homes, and is becoming one of
the most far-reaching communications technologies in the
country’, but it seems it won’t ever reach the farmhouse nor
its meters located 50m away in a field full of hay. Thus, I
have another job for life!
From Bard to Worse
Microsoft’s Bing search engine now offers a ‘chatty’ style of
working based on ChatGPT which I find makes a pleasant
change from the usual mindless Google searches. Microsoft Windows is also expected to incorporate a humanoid
chatbot Help system in future software releases. Meantime, Google is developing Google Bard, an experimental
AI chatbot designed to write creative content and answer
questions ‘thoughtfully’. I asked Bard who Alan Winstanley
The blitzortung.org website shows near real-time progress of
thunderstorms all around the world.
was and, after thinking about it, Bard replied that ‘Alan
Winstanley is... the Online Editor of the UK’s Practical
Electronics Magazine, and has written electronics tutorials
and magazine features since the 1970s.’ Nice to be reminded. But Bard then blew it by adding that ‘Winstanley is a
regular speaker at electronics events, and is a member of
the British Electronics Association. He is also a Fellow of
the Institution of Engineering and Technology.’ Sadly, I’m
none of those things! Try it out at: https://bard.google.com
In other news, the European Space Agency (ESA) successfully launched the last mission of its Ariane 5 heavy
lifter on 5 July – ESA was keen to boast of its ‘Franco-German success’, transporting two satellites into space for
the French and German governments. Nearly 120 Ariane
5 rockets have been launched in total, and previous missions included launching LEO satellites for OneWeb as well
as the James Webb Space Telescope. ESA also previously
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Practical Electronics | September | 2023
15
Artist’s view of the configuration of
Ariane 6 using four boosters. It will
be ESA’s next heavy-lift vehicle.
used Soyuz rocket launchers until the
Ukraine invasion torpedoed all co-operation with Russia’s Roscosmos; the
same problem caused a set-back for
OneWeb’s launch schedule.
This extremely convincing deep-fake
movie impersonates UK consumer
champion Martin Lewis promoting
phony investments.
16
Now ESA’s focus is on the forthcoming Ariane 6, which will launch from
French Guiana and will use either two or
four boosters depending on the payload.
Interested readers can learn more about
Ariane 6 at: https://bit.ly/pe-sep23-esa
I’m enjoying using my Ecowitt network-enabled weather station which
displays readings and statistics from
the last 72 hours on a 7-inch TFT colour
LCD display (Net Work, July 2023). The
Ecowitt HP2551 can read data from
up to eight 868MHz (in the UK) outdoor wireless sensors, and they have
a range of 100m. I’ve had no problems
at all receiving wireless data from the
remote sensor array. I’ve now got my
sights on adding a lightning sensor,
which detects and counts lightning
strikes in the area (the website https://
map.blitzortung.org is handy for showing the progress of live thunderstorms
online). The Ecowitt range is available from Amazon, but do benchmark
prices carefully as these vary hugely
over time. I’ve added lots of screenshots showing typical displays on my
July 2023 Net Work summary blog at:
https://bit.ly/pe-sep23-blog
Next, news of the TP-Link Tapo
smart devices that I’m trying at home
(see Net Work, December 2022). One
Tapo smart bulb has already been replaced under warranty, though the
cost of return postage made it barely
worth doing. I find the Alexa skill
integration works maybe 85% of the
time, possibly due to bottlenecks in
Amazon’s cloud: sometimes a Tapo
smart bulb or socket won’t respond for
up to 10-20 seconds, if at all, leaving
me guessing what’s going to happen
next. The Tapo app is the only other
means of controlling it, always assuming I have my smartphone with me. To
be fair, Tapo is a low-cost consumer
range of smart devices, and in my experience it’s alright as far as it goes,
but personally I wouldn’t feel confident in trusting it to control anything
other than basic non-essential loads
like lighting or audio gear.
Regular web users will recognise scam adverts when they see
them, but a new and deeply worrying trend is emerging that involves
deep-fake videos of well-known presenters promoting bogus financial
services. A deep-fake movie showing Martin Lewis, the popular UK
consumer campaigner, talking about
Elon Musk’s supposed new ‘investment project’ for UK investors is
utterly convincing. Lewis is pushing hard to have scam ads like these
banned because, in his words, people
will lose money and they will ruin
lives. Maybe alert your friends and
family about them – a clip can be seen
at: https://bit.ly/pe-sep23-scam
Finally, this month, more than 1,000
LED drones were used by Sky Elements
in a Guinness world-record display
to celebrate the 4 July in Texas. The
display showcased milestone events
in American history in the night-time
skies and extracts of the colourful show
can be seen on a YouTube movie at:
https://bit.ly/pe-sep23-led
The author can be reached at:
alan<at>epemag.net
Practical Electronics | September | 2023
