This is only a preview of the April 1995 issue of Silicon Chip. You can view 29 of the 96 pages in the full issue, including the advertisments. For full access, purchase the issue for $10.00 or subscribe for access to the latest issues. Articles in this series:
Items relevant to "Build An FM Radio Trainer; Pt.1":
Items relevant to "A Photographic Timer For Darkrooms":
Items relevant to "Balanced Microphone Preamplifier & Line Mixer":
Items relevant to "50W/Channel Stereo Amplifier; Pt.2":
Articles in this series:
Articles in this series:
Articles in this series:
|
Publisher & Editor-in-Chief
Leo Simpson, B.Bus.
Editor
Greg Swain, B.Sc.(Hons.)
Technical Staff
John Clarke, B.E.(Elec.)
Robert Flynn
Reader Services
Ann Jenkinson
Advertising Enquiries
Leo Simpson
Phone (02) 979 5644
Regular Contributors
Brendan Akhurst
Garry Cratt, VK2YBX
Marque Crozman, VK2ZLZ
Julian Edgar, Dip.T.(Sec.), B.Ed
John Hill
Jim Lawler, MTETIA
Philip Watson, MIREE, VK2ZPW
Jim Yalden, VK2YGY
Bob Young
Photography
Stuart Bryce
SILICON CHIP is published 12 times
a year by Silicon Chip Publications
Pty Ltd. A.C.N. 003 205 490. All
material copyright ©. No part of
this publication may be reproduced
without the written consent of the
publisher.
Printing: Macquarie Print, Dubbo,
NSW.
Distribution: Network Distribution
Company.
Subscription rates: $49 per year
in Australia. For overseas rates, see
the subscription page in this issue.
Editorial & advertising offices:
Unit 34, 1-3 Jubilee Avenue, Warrie
wood, NSW 2102. Postal address:
PO Box 139, Collaroy Beach, NSW
2097. Phone (02) 979 5644. Fax
(02) 979 6503.
PUBLISHER'S LETTER
The Gordon Dam
must not be emptied
It could only happen in a rich democracy: this recent proposal that the Gordon
Dam in Tasmania should be emptied
so that the original Lake Pedder can be
restored. To put it bluntly, this is environmentalism gone crazy. I well remember
writing an editorial in the June 1982
issue of “Electronics Australia” opposing
the then proposed Gordon River dam
scheme. This seemed to be a completely
unnecessary scheme and one which was
eventually stopped by the Federal Government in 1984. However, the Gordon
Dam which flooded the original Lake Pedder is a much larger scheme which
was completed in 1976. It was described in detail in the February 1991 issue
of SILICON CHIP, as part of the popular series entitled “The Story of Electrical
Energy” by Bryan Maher. At present, it has an installed generating capacity of
432 megawatts and is the major component of Tasmania’s electricity supply.
Now I don’t really think that the dam will be emptied but, in today’s topsy
turvy world, you never know what crazy scheme might succeed. So let’s look at
the proposal objectively. Sure, the original Lake Pedder was a pleasant enough
lake although the only aspect that made it unusual was the salmon pink sand
beach which showed when the water level was down – when the water level
was high, the beach was not visible. Offsetting the subtle colour of the sand
was the dirty brown colour of the water, a result of tannin leached from the nut
grass which is prevalent in the catchment region. Actually, the water looks like
a cola drink. Very few people ever saw the original lake since it was accessible
only to trekkers or by plane (which had to land on the beach).
Today, we have a much larger body of (still brown) water which is visited
by tens of thousands of tourists a year. If it were to be emptied, it would be a
financial and environmental disaster. Not only would Tasmania lose a substantial
portion of its electricity generating capacity but all the tourist dollars produced
by this major attraction would vanish.
And how would all the vegetation in the area now covered by water (260,000
square kilometres) be restored? Would the dam wall with its 280,000 tonnes of
steel and concrete be demolished and disposed off? What about the two other
dams in the scheme which also raise the water level? And what about the very
expensive generating plant? Would that be scrapped? And how would Australia
then stand in its attempts to reduce carbon dioxide emissions in the years to
come, if hydroelectricity has to be replaced by fossil fuels? How would Tasmania
cope for water and electricity in the next drought?
These questions and many others have very unsatisfactory answers. Or very
expensive answers. Really, the whole proposal is crazy and should be dismissed
out of hand. Australia may be a rich democracy but we aren’t that rich and nor,
I hope, are we that silly!
Leo Simpson
ISSN 1030-2662
WARNING!
SILICON CHIP magazine regularly describes projects which employ a mains power supply or produce high voltage. All such projects should
be considered dangerous or even lethal if not used safely. Readers are warned that high voltage wiring should be carried out according to the
instructions in the articles. When working on these projects use extreme care to ensure that you do not accidentally come into contact with
mains AC voltages or high voltage DC. If you are not confident about working with projects employing mains voltages or other high voltages,
you are advised not to attempt work on them. Silicon Chip Publications Pty Ltd disclaims any liability for damages should anyone be killed
or injured while working on a project or circuit described in any issue of SILICON CHIP magazine. Devices or circuits described in SILICON
CHIP may be covered by patents. SILICON CHIP disclaims any liability for the infringement of such patents by the manufacturing or selling of
any such equipment. SILICON CHIP also disclaims any liability for projects which are used in such a way as to infringe relevant government
regulations and by-laws.
Advertisers are warned that they are responsible for the content of all advertisements and that they must conform to the Trade Practices Act
1974 or as subsequently amended and to any governmental regulations which are applicable.
2 Silicon Chip
|