Practical
Electronics
Volume 55. No. 07
July 2026
ISSN 2632 573X
Contents
Projects and Circuits
RP2350B Development Board by Geoff Graham & Peter Mather
4
Think of this as the Raspberry Pi Pico 2’s bigger sibling – more pins, more I/O, more
speed, more storage and more memory. It’s perfect for breadboarding, too. Like the
Picos, it can be purchased pre-assembled.
USB Solar Charging by Julian Edgar
20
This simple electronic project allows you to charge and power all your USB devices
from a low-cost solar system. It’s inexpensive to put together, and once you’ve built it,
charging your devices won’t cost a cent!
The SmartProbe by Andrew Levido
23
The SmartProbe is an extremely handy little device for making voltage and continuity
measurements. It won’t replace your multimeter, but it is designed to be the first piece
of test equipment you reach for when debugging or repairing a circuit.
Series, Features and Columns
Audio Out by Jake Rothman
10
All-pass filters, part four – new PCBs & symmetricisers. We start by describing an
updated all-pass filter board plus two polarity inversion switches that can be used with
it. We then go into a detailed history of symmetricisers used for radio broadcasting.
Circuit Surgery by Ian Bell
34
Measuring circuit frequency response using a PC sound card, part 10: differential
amplifiers and line drivers. We continue looking at differential line drivers and also
consider differential receivers, including practical implementations of both.
Techno Talk by Max the Magnificent
42
Tracks and tribulations – a ramble through the evolution of PCB layout, from tape and
scalpels to overcaffeinated autorouters and today’s AI-powered tools.
Mains Earthing Systems by Brandon Speedie
44
The Earth is an integral part of our power system. It can be used to improve electrical
safety, reduce energy losses or save on the cost of a dedicated conductor. Here, we
look at the different Earthing systems used worldwide and how they work.
Max’s Cool Beans by Max The Magnificent
48
Weird & Wonderful Arduino Projects, part 19: marble mayhem and tilting tomfoolery.
We add an accelerometer to our Retro Games Console so we can play by tipping it.
This IMU can also measure the rate of rotation and even magnetic orientation.
Teach-In 12.9: the World of Wireless by Mike Tooley
56
RF sources and oscilators: this month, we take a deep dive into RF sources,
explaining how to get the best out of a variety of phase-locked loop (PLL) signal
and marker/generator modules, plus direct digital synthesis (DDS) chips.
The benefits of PCB inspection reports by Steve Mansfield-Devine (PCBWay) 66
However much you test your product designs, there will always be factors outside your
control that affect your final product. One of the most important of these is the quality
of the PCBs you receive from your chosen fabrication house.
Power Electronics, part four by Andrew Levido
69
AC-to-DC conversion using rectifiers – rectifier-type AC-DC converters predate the
DC-DC converters we have been studying so far, by many decades. This month, we
will look into these deceptively simple circuits.
The Fox Report by Barry Fox
Balcony solar is popular in Germany and it will soon be coming to the UK.
Made in Australia & the UK.
Written in Britain, Australia,
the USA and Ireland.
Read everywhere.
© Silicon Chip Publications Pty Ltd 2026
Copyright in all drawings, photographs, articles, technical
designs, software and intellectual property published in
Practical Electronics is fully protected, and reproduction
or imitation in whole or in part are expressly forbidden.
The August 2026 issue of Practical Electronics will be
published on Tuesday, 7th of July, 2026 (see p84).
Practical Electronics | July | 2026
78
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