Practical
Electronics Contents
Projects and Circuits
2× 12V Battery Balancerby Nicholas Vinen 14
This compact device keeps series connected batteries balanced and safe.
Deluxe Frequency Switchby John Clarke 20
Switch devices on/off based on frequency from most sensor signals up to 10kHz.
Using Cheap Asian Electronic Modules – Part 16 by Jim Rowe 26
Learn to use a programmable frequency module based on the ADF4351 IC that
produces sinewaves from 35MHz to 4.4GHz with crystal accuracy
USB Port Protectorby Nicholas Vinen 31
Don’t let one small ‘oops’ fry your PC – protect it with this essential device!
MIDI Ultimate Synthesiser – Part 4 by Paul Cooper 36
This month, we add the circuits for the synth’s modulation sources, which can be
used to modify the characteristics of the sound being produced.Series, Features and Columns
The Fox Reportby Barry Fox 8
The future of TV
Techno Talkby Mark Nelson 10
How’s your soldering?
Net Work by Alan Winstanley 12
Embracing LED lights... 5G and microsatellites will transform our digital world
Teach-In 2019 – Powering Electronics by Mike Tooley 44
Part 6: Voltage multipliers
Audio Out by Jake Rothman (article) and Mike Grindle (PCB and circuit) 51
Backing Baxandall – Part 2
Circuit Surgery by Ian Bell 54
Comparator circuit design
PIC n’ MIX by Mike Hibbett 58
Small, cheap and powerful – Part 1
Max’s Cool Beans by Max The Magnifi cent 61
The glorious Maxfi eld-Farr 4-bit HRRG Computer
Make it with Micromite by Phil Boyce 64
Part 4: Digital inputs and outputs
Electronic Building Blocks by Julian Edgar 76
Multi-pulserRegulars and Services
Subscribe to Practical Electronics and save money 4
Practical Electronics back issues CD-ROM – great 15-year deal! 6
Reader services – Editorial and Advertising Departments 7
Editorial 7
Phew!
Exclusive Microchip reader offer 19
Win an AVR-IoT WG Development Board
Teach-In bundle – what a bargain! 25
Practical Electronics – get your back issues here! 43
Practical Electronics CD-ROMS for electronics 70
A superb range of CD-ROMs for hobbyists, students and engineers
Direct Book Service 73
Build your library of carefully chosen technical books
Teach-In 8 77
Practical Electronics PCB Service 78
PCBs for Practical Electronic projects
Advertiser index 79
Next month! – highlights of our next issue of Practical Electronics 80Volume 48. No. 5
May 2019
ISSN 0262 3617© Electron Publishing Limited 2019
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 June 2019 issue of Practical Electronics will be
published on Thursday, 2 May 2019 – see page 80.