Practical
Electronics
Volume 53. No. 6
June 2024
ISSN 2632 573X
Contents
Projects and Circuits
Wi-Fi Time Source for GPS Clocks by Tim Blythman
15
The Raspberry Pi Pico W can be used as a substitute for GPS modules in existing time
keeping designs, for when you can’t get a reliable GPS signal. It gets the time from an
internet NTP server via Wi-Fi and is accurate to a fraction of a second.
Heart Rate Sensor Module by Jim Rowe
24
This design features an Analog Devices AD8232 heart rate monitor front-end IC
which provides a low-cost way to monitor the operation of the heart via an Arduino
MCU or similar.
Loudspeaker Test Jig by Phil Prosser
28
Use your PC’s sound card to measure loudspeaker performance, inductors, capacitors
and complex impedances. With this Jig and appropriate software, measuring and
tweaking crossovers, cabinets and speakers is easy.
Setting up and using Room EQ Wizard by Phil Prosser
40
This accompanying article for the Speaker Test Jig explains how to set up and use the
freely-available Room EQ Wizard (REW) or Speaker Workshop software to help you
design and tweak loudspeakers.
Series, Features and Columns
Techno Talk by Max The Magnificent
Program that!
8
Net Work by Alan Winstanley
10
Reports on USB-type chargers, including Power Delivery (PD) rapid charging and GaN
devices. Plus, a new EV with a long-range, fast-charging solid-state battery from China.
Teach-In 2024 – Learn electronics with the ESP32 by Mike Tooley
Part 4 – Using LED displays
44
Max’s Cool Beans by Max The Magnificent
Arduino Bootcamp – Part 18
52
Audio Out by Jake Rothman
Switching in audio equipment – Part 1
58
Circuit Surgery by Ian Bell
Topics in digital signal processing – ADCs
63
Regulars and Services
Made in the UK.
Written in Britain, Australia,
the US and Ireland.
Read everywhere.
© Electron Publishing Limited 2024
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 July 2024 issue of Practical Electronics will be
published on Thursday, 6 June 2024 – see page 72.
Practical Electronics | June | 2024
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Next month! – highlights of our next issue of Practical Electronics
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