Practical
Electronics
Volume 49. No. 12
December 2020
ISSN 2632 573X
Contents
Projects and Circuits
Clever Controller for a Dumb Battery Charger by John Clarke
Most cheap battery chargers are pretty dumb! Upgrade them with this clever
controller for ooded lead acid,
or even i e 4 rechargeable batteries.
16
LFSR Random Number Generator by Tim Blythman
28
sing a handful of logic s you can digitally generate a pseudo random number
sequence. handy circuit to have it even or s ith our
hristmas ree.
High-Power 45V/8A Variable Linear Supply – Part 3 by Tim Blythman
34
o it s time to finish off your supply s case, mount the components inside, attach
the front panel controls, ire it up and perform the final calibration/testing.
Series, Features and Columns
The Fox Report by Barry Fox
mart meters for hose benefit
8
Techno Talk by Mark Nelson
riumph or travesty
10
Net Work by Alan Winstanley
he rise of the most lucrative of all electronic products the car. rom o e to
must have purchase, the electric car is a revolution happening right no .
12
Building a Hi-Fi amp on the cheap by Julian Edgar
sing a salvaged amplifier is a great starting point for assembling lo
41
Audio Out by Jake Rothman
heremin udio mplifier
art
46
Make it with Micromite by Phil Boyce
art
nalogue inputs and servos
50
Circuit Surgery by Ian Bell
icro ap
simulator
54
a s ool eans by Max The Magnificent
lashing
s and drooling engineers
art
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 January 2021 issue of Practical Electronics will be
published on Thursday, 3 December 2020 – see page 72.
Practical Electronics | December | 2020
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