Practical
Electronics
Volume 51. No. 2
February 2022
ISSN 2632 573X
Contents
Projects and Circuits
Arduino-based Adjustable Power Supply by Tim Blythman
A handy power supply with voltage and current monitoring and limiting, built as
an Arduino shield that’s convenient and easy to set up and use.
14
Battery Monitor Logger by Tim Blythman
Knowing the condition of your batteries is essential for keeping them healthy
longterm – this project can monitor and log all your battery’s vital statistics.
22
Electronic Wind Chimes by John Clarke
30
Our Electronic Wind Chimes removes your reliance on the wind, and even gives you
the possibility of playing your own tunes, enriching the experience!
Mini Digital AC Panel Meters by Jim Rowe
38
We look at low-cost meters designed to measure AC voltages and currents. Some of
them can even calculate and display power, energy consumption and frequency.
Series, Features and Columns
Techno Talk by Mark Nelson
Should we be worried?
8
Net Work by Alan Winstanley
10
The latest developments in the electricity generation sector and ideas for streaming
favourite radio and music channels – plus a practical ‘Net Workshop’ topic!
KickStart by Mike Tooley
Part 7: Plug and play with I2C
42
Flowcode Graphical Programming by Martin Whitlock
RedBoard and PICs – Part 2
47
Max’s Cool Beans by Max The Magnificent
Flashing LEDs and drooling engineers – Part 24
52
Audio Out by Jake Rothman
Analogue Vocoder – Part 4: Driver Amplifier
56
Circuit Surgery by Ian Bell
Op amp offsets – Part 1
60
Make it with Micromite by Phil Boyce
Part 33: Using CRC with iButtons and the Micromite
64
Wireless for the Warrior
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Reader services – Editorial and Advertising Departments
Editorial
Happy New Year!
Exclusive Microchip reader offer
Win a Microchip WLR089 Xplained Pro Evaluation Kit
PE Teach-In 8
Practical Electronics PCB Service
PCBs for Practical Electronics projects
Classified ads and Advertiser index
Next month! – highlights of our next issue of Practical Electronics
2
4
6
7
7
Regulars and Services
Flowcode
C
void interrupt(void)
{
if (intcon & 4)
{
clear_bit(intcon, 2);
FCM_INTERRUPT_TMR
o();
Assembly
movlw D′7′
bsf STATUS, RP0
bcf STATUS, RP1
movwf _adcon1
movlw D′192′
movwf _option_reg
Hex
:040000008A01122837
:08000800F000F00S030
EF10000
:10001000040EF2000A0
EF300BA110A122928352
86C
:2000200D928FE28073
Made in the UK.
Written in Britain, Australia,
the US and Ireland.
9
46
68
71
72
Read everywhere.
© Electron Publishing Limited 2022
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 March 2022 issue of Practical Electronics will be
published on Thursday, 3 February 2022 – see page 72.
Practical Electronics | February | 2022
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