Practical
Electronics
Volume 49. No. 6
June 2020
ISSN 2632 573X
Contents
Projects and Circuits
AM/FM/CW Scanning HF/VHF RF Signal Generator – Part 1
by Andrew Woodfield
This low-cost, easy-to-build and user-friendly RF signal generator covers from
100kHz–50MHz and 70–120MHz, and is usable up to 150MHz.
14
Low-cost 3.5-inch touchscreen for the Arduino or Micromite by Tim Blythman
We’ve had many projects using 320 × 240 pixel, 2.8-inch colour touchscreens.
Now we’ve found larger, higher-resolution displays that only cost a little more.
22
Ultra-low-distortion Preamplifier with Tone Controls – Part 3 by John Clarke
This high-performance Audio Selector expands the number of inputs to the Ultralow-distortion Preamplifier, or ‘upgrade’ just about any piece of audio equipment.
32
Series, Features and Columns
Publisher’s statement by Matt Pulzer
A message to all readers of Practical Electronics
6
Techno Talk by Mark Nelson
Beyond back-of-the-envelope design
9
Net Work by Alan Winstanley
10
In an era of lockdown and social distancing the Internet is more important than ever.
We look at apps, security and some pleasingly welcome diversions.
Circuit Surgery by Ian Bell
Class-D, G and H amplifiers
40
Practically Speaking by Mike Hibbett
Introduction to surface-mount technology – Part 2
44
Make it with Micromite by Phil Boyce
Part 17: Building the Micromite Robot Buggy
48
Audio Out by Jake Rothman
PE Mini-organ – Part 1
54
Max’s Cool Beans by Max The Magnificent
Home working and flashing LEDs
58
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 July 2020 issue of Practical Electronics will be
published on Thursday, 4 June 2020 – see page 72.
Practical Electronics | June | 2020
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Next month! – highlights of our next issue of Practical Electronics
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