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MARCH 1988
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TANDY'S NEW CD-1500 is a
mid- priced CD player that comes
with remote control as
standard. We tell you how it
performs in our review starting
page 16.
FEATURES
6 New Life for Radio-Cassette Players by Homer Davidson
12
16
65
76
81
Simple service tips to bring back the good sound
Vintage Radio: How it Began by John Hill
From spark transmitters to the Audion
Tandy's CD-1500 CD Player by Leo Simpson
Mid-priced unit has remote control
High, Low, Sink and Source by Leo Simpson
What the jargon means
The Evolution of Electric Railways by Bryan Maher
Pt.5 - Electrics in Australia
Digital Fundamentals, Pt.5 by Louis Frenzel
Counters & shift registers
DON'T PUT UP with
interruptions from extension
phones. When you pick up one
telephone, this simple device
automatically cuts the
extension phones dead.
Details page 18.
PROJECTS TO BUILD
18 Line Grabber for Telephones by Greg Swain
Pick up one phone & it cuts the others dead
26 Remote Switch For Car Burglar Alarms by John Clarke
The transmitter attaches to your keyring
40 Endless Loop Tape Player by Greg Swain
Use it as a novel doorbell
43 Technilab 301 Function Generator by David Whitby
Useful test instrument doubles as a signal tracer
56 Old-Time Crystal Radio by John Hill
Its performance will surprise you
60 Build Your Own Light Box by Leo Simpson
Low cost & easy on the eyes
PRESS THE BUTTON on a
small keyring transmitter and
this project will automatically
turn your car's burglar alarm
on and off. Construction
begins on page 26
SPECIAL COLUMNS
50 Serviceman's Log by the original TV serviceman
A baffling exercise
68 Amateur Radio by Garry Cratt
Antennas for the VHF & UHF bands
72 The Way I See It by Neville Williams
The quest for the ultimate in hifi sound is half the fun!
DEPARTMENTS
2 Publisher's Letter
3 Mailbag
4 News & Views
15 Bookshelf
38 Circuit Notebook
88 Product Showcase
94 Ask Silicon Chip
96 Market Centre
FANCY A BARKING doorbell?
This endless loop tape player
is the answer. It can also serve
as a novel pre-recorded
message system. See page 40.
MARCH 1988
1