Practical
Electronics
Editorial offices
Volume 50. No. 8
August 2021
ISSN 2632 573X
Editorial
Practical Electronics Adverts Tel
01273 777619
1 Buckingham Road
Mob 07973 518682
Brighton
Email pe<at>electronpublishing.com
East Sussex BN1 3RA
Projects, projects, projects…
We have a pleasingly eclectic collection of projects for you this
month. First up is the Ol’ Timer, an intriguing take on a digital
clock that manages to tell the time without numbers or hands.
A nice design bonus is the clever capacitive-touch technology
built into its PCB in place of push buttons. We first covered this
last month (see: ATtiny816 Breakout and Development Board
with Capacitive Touch). It’s a handy technology that could be
transferred to many other projects. Why not give it a try?
Editor
Matt Pulzer
General Manager
Louisa Pulzer
Digital subscriptions Stewart Kearn Tel 01202 880299
Online Editor
Alan Winstanley
Web Systems
Kris Thain
Publisher
Matt Pulzer
Next, for all you RF fans, we have a Low-cost, Wideband Digital
RF Power Meter that uses some cheap pre-built modules that
when assembled produce an excellent piece of instrumentation –
thoroughly recommended!
Practical Electronics
Electron Publishing Limited
1 Buckingham Road
Brighton
East Sussex BN1 3RA
Tel
01273 777619
Mob 07973 518682
Fax 01202 843233
Email pe<at>electronpublishing.com
Web www.electronpublishing.com
Advertisement offices
Print subscriptions
Practical Electronics Subscriptions
PO Box 6337
Bournemouth BH1 9EH
Tel
01202 087631
United Kingdom
Email pesubs<at>selectps.com
Technical enquiries
We regret technical enquiries cannot be answered over the
telephone. We are unable to offer any advice on the use, purchase,
re a r or od fi a o of o
er al e
e or e or ora o
or od fi a o of des s
l s ed
e a a e e a o
provide data or answer queries on articles or projects that are
ore a fi e years old
Questions about articles or projects should be sent to the editor
by email: pe<at>electronpublishing.com
Projects and circuits
All reasonable precautions are taken to ensure that the advice and
data given to readers is reliable. We cannot, however, guarantee
it and we cannot accept legal responsibility for it.
A number of projects and circuits published in Practical Electronics
employ voltages that can be lethal. You should not build, test,
modify or renovate any item of mains-powered equipment unless
you fully understand the safety aspects involved and you use an
RCD (GFCI) adaptor.
Component supplies
We do not supply electronic components or kits for building the
projects featured, these can be supplied by advertisers. We
advise readers to check that all parts are still available before
commencing any project in a back-dated issue.
Advertisements
Although the proprietors and staff of Practical Electronics take
reasonable precautions to protect the interests of readers by
e s r
as far as ra a le a ad er se e s are o a fide
the magazine and its publishers cannot give any undertakings
in respect of statements or claims made by advertisers, whether
these advertisements are printed as part of the magazine, or in
inserts. The Publishers regret that under no circumstances will
the magazine accept liability for non-receipt of goods ordered, or
for late delivery, or for faults in manufacture.
Transmitters/bugs/telephone equipment
We advise readers that certain items of radio transmitting and
telephone equipment which may be advertised in our pages
cannot be legally used in the UK. Readers should check the law
efore y a y ra s
or ele o e e
e as a fi e
o fis a o of e
e a d or
r so e
a res l fro
illegal use or ownership. The laws vary from country to country;
readers should check local laws.
Practical Electronics | August | 2021
Is there any one of us who hasn’t used at least one 78xx linear
regulator? For decades, their simplicity and reliability have made
them the go-to solution for quick and easy regulated power supply
construction. They do have one major problem though – they can
be inefficient. Now, though, that is a problem of the past thanks to
the Switchmode Replacement for 78xx Regulators; a brilliant little
design that enables you to build a drop-in replacement for 78xx
regulators with a much more efficient switcher.
PCBs back in stock!
Recently, we’ve had a couple of minor problems with PCB
deliveries that unfortunately turned into rather a long delay – so,
apologies to everyone who’s had to wait for July’s boards. We’ve
also stocked up on some older projects that had run low or even
reduced to zero. So, if you’ve been disappointed recently when
looking for a particular project’s PCB then do try again, almost
everything from the last five years is now in the shop.
One other shop reminder – don’t forget that for all your Audio Out
requirements Jake Rothman is now running the ‘Audio Out Shop’.
See page 5 for hard-to-find goodies at great prices.
EU VAT
Finally, a message for all our friends in the European Union.
From 1 July, the EU will reduce the minimum value on imports
that are liable for VAT from €22 to €0. We know why (no, it’s
nothing to do with Brexit!) – the EU has been losing billions in
VAT through under-reported ecommerce transactions, mostly
from China. Unfortunately, this may mean even single issues of
non-EU magazines (ie, PE) become liable for VAT at their point of
entry. In practice, it’s hard to believe this is anyone’s interest, but
we will have to wait and see. The (unofficial) mood among EU
post offices and shippers is that this would become an unbearable
administrative burden for a truly tiny return, but the official
position on magazines has not yet been declared. When we know
more we will tell you.
Keep well everyone
Matt Pulzer
Publisher
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