Practical
Electronics
Volume 49. No. 2
February 2020
ISSN 2632 573X
Contents
Projects and Circuits
Audio DSP – Part 2 by Phil Prosser (design) and Nicholas Vinen (words)
In this second instalment we finish describing the circuit and present the parts
list and board assembly instructions.
15
Motion-Triggered 12V Switch by Nicholas Vinen
ant to communicate with a micro connected to mains or a high- oltage supply
Risky Not ust to the de ice but to you as well ere’s the safe way to do it.
26
USB Keyboard and Mouse Adaptor for Micros by Tim Blythman
This pro ect makes it simple to connect a SB keyboard or mouse to any micro
It’s small easy to build and it won’t break the bank
31
Using Cheap Asian Electronic Modules – Part 21 by Jim Rowe
Learn to use the D Player Mini a low-cost digital audio player module.
38
Colour Maximite Computer – Part 4 by Phil Boyce
Maximite graphics capabilities demo programs and hardware control.
42
The Fox Report by Barry Fox
ood: could be better
8
Techno Talk by Mark Nelson
Not one but two
10
Series, Features and Columns
Net Work by Alan Winstanley
12
The launch of our new online shop means a significant upgrade from our pre ious
irtual store and lays the foundation for a whole new web presence for P .
Circuit Surgery by Ian Bell
Logic le els – Part 2
47
Practically Speaking by Mike Hibbett
PCB digital microscope
52
Using Stepper Motors by Paul Cooper
Bipolar stepper motor dri er modules
54
a s ool eans by Max The Magnificent
The wanters the wishers and the makers
59
Audio Out by Jake Rothman
P Mini-monitor crosso er for
62
a ecor dri ers – Part 1
Make it with Micromite by Phil Boyce
Part 13: Controlling R B L Ds and building a Mood Light
66
Electronic Building Blocks by Julian Edgar
Re-purposing an old camera battery
76
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appy New ear
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Next month! – highlights of our next issue of Practical Electronics
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Regulars and Services
Made in the UK.
Written in Britain, Australia,
the US and Ireland.
Read everywhere.
© Electron Publishing Limited 2020
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 2020 issue of Practical Electronics will be
published on Thursday, 6 February 2020 – see page 80.
Practical Electronics | February | 2020
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Stepper motor image on cover and contents page courtesy of Pololu Robotics & Electronics, pololu.com
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