Practical
Electronics
ol me
o
July 2020
ISSN 2632 573X
Contents
Projects and Circuits
Speech Synthesiser with the Raspberry Pi Zero by Tim Blythman
Could your electronic gadgets speak to you? Yes! – and in just about any
language with a low-cost Raspberry Pi, simple hardware and some software.
14
AD584 Precision Voltage References by Jim Rowe
How to use three low-cost precision voltage reference modules based on the
AD584 IC. Each has a different version of this chip and a unique design.
22
AM/FM/CW Scanning HF/VHF RF Signal Generator – Part 2
28
by Andrew Woodfield
Ideal entry-level test instrument for anyone into radio: capable, yet low in cost
and quite easy to build. This month, we assemble it and getting it up and running.
High-current Solid-state 12V Battery Isolator by Bruce Boardman
36
Charge an auxiliary RV battery, but disconnect it once the engine shuts down, so
that the vehicle battery can t accidentally go at. t s robust, cheap and easy to build.
eries
eat res and
lis er s statement by Matt Pulzer
A message to all readers of Practical Electronics
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 August 2020 issue of Practical Electronics will be
published on Thursday, 2 July 2020 – see page 72.
Practical Electronics | July | 2020
6
Techno Talk by Mark Nelson
Silly stuff for the silly season
9
Net Work by Alan Winstanley
Online security is a never-ending quest for effectiveness and usability. This month,
Net Work looks at choosing and setting up Two-Factor Authentication.
10
Circuit Surgery by Ian Bell
LTspice sources and waveform import/export
43
Audio Out by Jake Rothman
PE Mini-organ – Part 2
48
a e it it
icromite by Phil Boyce
Part 18: Animated eyes for the Micromite Robot Buggy
51
n i by Mike Hibbett
Part 1: Introducing the PIC18 family
54
a s ool eans by Max The Magnificent
Flashing LEDs and drooling engineers – Part 5
58
Electronic Building Blocks by Julian Edgar
Modifying solar garden lights
62
Wireless for the Warrior
PE Teach-In 9
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