Practical
Electronics
Volume 51. No. 4
April 2022
ISSN 2632 573X
Contents
Projects and Circuits
64-key MIDI Matrix – Part 1 by Tim Blythman
This simple project turns an Arduino into an 8x8-key MIDI matrix. You can
customise it via software and program it to act as a MIDI pass-through.
16
Digital FX Unit – Part 1 by John Clarke
This packed effects box will produce unique sounds from an electric guitar, bass,
violin or icro hone rea
or ithin the e ects loo o an a lifier or i er.
26
High-current Battery Balancer – Part 1 by Duraid Madina
Proper balancing is critical for long battery life, especially for lithium-based types.
nli e any other designs this one is e ficient ith little heat or aste.
38
Techno Talk by Mark Nelson
Go eco, get ethical!
8
The Fox Report by Barry Fox
Right to repair, Windows 11 and 1 Gig broadband
10
Net Work by Alan Winstanley
A round-up of trends emerging in image scanners and the fast-changing world
of space and satellite technology.
12
Circuit Surgery by Ian Bell
The LM35 temperature sensor
46
Flowcode Graphical Programming by Martin Whitlock
Part 3: LCD temperature monitor
49
Audio Out by Jake Rothman
Analogue Vocoder – Part 6: Universal Audio PSU
56
a s Cool eans y ax The agnificent
Flashing LEDs and drooling engineers – Part 26
62
Make it with Micromite by Phil Boyce
Part 35: Mini-Project: iButton-controlled Electronic Door Lock
66
Wireless for the Warrior
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2
4
7
7
Series, Features and Columns
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
14
15
55
70
72
Made in the UK.
Written in Britain, Australia,
the US and Ireland.
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 May 2022 issue of Practical Electronics will be
published on Thursday, 7 April 2022 – see page 72.
Practical Electronics | April | 2022
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