December 1990
THIS DC-DC CONVERTER
provides split supply rails of up
to ±50Vfrom a +12V supply so
that you can run a high power
audio amplifier in your car.
Details page 24
FEATURES
4 Understanding PC Memory by Brian Richards
How to make the best use of the options
14 The Great Green CD Pen Controversy by Leo Simpson
We've done the tests to bring you the facts
98 The Story Of Electrical Energy, Pt.6 by Bryan Maher
Rebuilding old alternators to better than new
PROJECTS TO BUILD
24 DC-DC Converter For Car Amplifiers by John Clarke
Can be built to give supply rails from ±35V to ±50V
CAN YOU MAKE the big escape
by getting safely through the
tunnel? This clever game will test
your skill. Turn to page 38.
38 The Big Escape by Darren Yates
Can you escape from the remote prison camp?
54 Wiper Pulser For Rear Windows by John Clarke
Pulses the wiper on at the press of a button
70 Versatile 4-Digit Combination Lock by Gary Ioppolo
Easy-to-build circuit uses DIP switches for programming
SPECIAL COLUMNS
48 Serviceman's Log by the TV Serviceman
It sounds like Donald Duck
66 Vintage Radio by John Hill
Old radio books & magazines
82 Computer Bits by Jennifer Bonnitcha
Talk to the world: modem mysteries revealed
104 Amateur Radio by Garry Cratt
A 5W power amplifier for the 6-metre FM transmitter
RECENTLY, THERE HA VE been
claims that applying green dye to
the edges of compact discs can
improve their sound quality.
We've done the tests to bring you
the facts. See page 14.
110 Remote Control by Bob Young
Radio control receivers using amplitude modulation
DEPARTMENTS
3 Publisher's Letter
7 Mailbag
65 Subscription Page
80 Circuit Notebook
86 Product Showcase
93 Bookshelf
2
SILICON CHIP
96 Back Issues
Ask Silicon Chip
Index To Volume 3
Market Centre
Advertising Index
114
116
118
120
HERE'S A 4-DIGIT LOCK that
will prove useful in many
security applications. It's easy to
build & is programmed by setting
four on-bo~rd DIP switches.
Details page 70.