APRIL 1990
FEATURES
6 Servicing Your Microwave Oven by Leo Simpson
Simple jobs that you can do yourself
68 Taking The BASF CD Challenge by Leo Simpson
WITH THIS LOW COST field
strength meter, you can adjust
antennas to resonance & align
transmitters for maximum
output. Construction starts on
page 20.
Can chrome tape sound as good as compact disc?
83 High Density Data Storage from Philips
A promising new technique
PROJECTS TO BUILD
20 Relative Field Strength Meter by Ralph Holland
Lets you adjust antennas and align transmitters
28 Build A VOX With Delayed Audio by Darren Yates
Don't chop off the first syllable
46 Dual Tracking
:!: 50V Power Supply by Greg Swain
New switchmode design delivers up to 1.7 A
72 16-Channel Mixing Desk, Pt.3 by John
LOOKING FOR A dual trucking
power supply that can really
deliver the goods? This design
can provide up to ± 50V DC at
currents up to 1.7A. Details
page 46.
Clarke
Assembling the PC boards
SPECIAL COLUMNS
16 Vintage Radio by John Hill
Finding receivers from the 1920s
36 Computer Bits by Jennifer Bonnitcha
Mass storage devices -
bigger than Ben Hur
60 Serviceman's Log by the TV serviceman
It's an ill wind ... , as they say
88 Remote Control by Bob Young
Model aircraft aerodynamics
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r:;.,,.: ,:,r-.-, t \ •~5-~
IT'S AN ILL WIND that blows
nobody any good, us they say.
The serviceman was very busy
this month and it wus ull due to
wind! - see page 60.
94 Amateur Radio by Garry Cratt
Active CW filter for weak signal reception
DEPARTMENTS
2 Publisher's Letter
4 Mailbag
40 Circuit Notebook
66 Back Issues
97 Product Showcase
100 Ask Silicon Chip
101 Notes & Errata
102 Subscription Page
103 Market Centre
MOST VOICE OPERATED relay
circuits chop off the first syllable
of speech but not this unit. It
features an in-built audio delay
so that all the speech signal
passes through. See page 28.
APRIL 1990
1