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All the facilities available on this website are free and available to
all D.A.R.C.club members and non-members alike. We welcome
your
comments and suggestions.
Allways Refresh this page by pressing "Ctrl-F5" to ensure you see the
latest updates.
Solar X-rays: Geomagnetic
Field:
From: n3kl.org (10 min updates)
Click on the above pictures and visit www.spaceweather.com
and www.spaceweather.co.za
for more info on space weather and how it affects us. VHF Aurora: 144 MHz E-Skip in Europe:
144 MHz E-Skip in North America:
From GoodDX.net
SA-AMSAT Space symposium 2010
Durban 17 April 2010 www.saamsat.org.za
University of KwaZulu-Natal
School of Electronic, Electrical and Computer Engineering
Howard College Campus,
King George V avenue Glenwood Durban
08:00 Registration 09:00 Space Symposium 16:30 SA AMSAT Annual General Meeting
Programme Highlights
Opening Address
Professor Fambirai Takawira Telkom Professor of Digital Communications / Dean of Engineering
Keynote address
Dr Phil Mjwara, Director General Department of Science and Technology
Lessons learnt from SumbandilaSat (Oscar-67) commissioning, what can go wrong and how to recover.
K. F Mathapo SunSpace & Information Systems (Ltd)
The String Vibrator Experiment (SVE), an Experimental Payload on SumbandilaSat
Mark Gordon Eskom
VLF Experiment on SumbandilaSat
Andrew Collier, Department of Physics, University of KwaZulu-Natal
The Durban University of Technology Indlebe Radio Telescope
Stuart Macpherson Durban University of Technology
A new generation of South African student satellites
D.F. Visser, French South African Institute of Technology Cape Peninsula University of Technology
AfriSpace: Thinking local. Acting orbital
S. Bradford Inggs, Founder of AfriSpace
Lalea - a around the world balloon project
John Willescroft ZS6EF
Building an SA AMSAT CubeSat
Hans van de Groenendaal ZS6AKV
Open forum chaired by David Long ZS5FR
SA AMSAT President
Get full programme here
Watch this space for attendance Prizes
FEES
Early bird bookings before 9 April 2010
SA AMSAT and SARL members R 70.00
Non members R130.00
After 9 April 2010
SA AMSAT and SARL members R 100.00
Non members R 170.00
Students and Learners
The Department of Science and Technology is sponsoring 25 students to
attend free charge. Student card/proof of being a learner must be
provided. Attach a copy to the registration form
Register now. Early birds who register before 9 April get a discount. Click here to get form
CAN WE GET ANOTHER SATELLITE PAYLOAD FOR AMATEUR RADIO?
SA AMSAT will be making
proposals to DST. We need your imput. We are planning to hold a
teleconference of interested amateurs in the next few weeks to
discuss the type of payload. A linear transponfer 2m up and 70 cm down
would be of great benefit to promote amateur radio in Africa. Send us
an email if you would like to participate: saamsat AT intekom coza
If you are not already a member of SA AMSAT, join now. membership is only R60.00 per year and subs are now due.
There is a thread on this subject on the SARL Forums and the subject can be discussed on the DARC Facebook page. Get your thinking caps on and let's be prepared with some well thought out ideas.
There have been requests for the club CD again recently.
If you would like to order one for delivery at the next Meeting or
Swap-Shop contact Dave ZS5LPT and have your call put on a disk. SMS
Dave on 083 736 6935 or email via the club email.
The club CD has nearly
all of the software you would require for working digital
modes,
antennae design and much more. In total there is 700MB of Software on
the CD. The cost of the CD is a R 10.00 donation to the club.
All proceeds from the
sales are donated to the club.
Your GPS can be use for more than just APRS. Get
the whole family involved in a little adventure. There are hundreds of
little
treasure hunts around Durban
just waiting to be found. Log on to www.geocaching.com
and register to see what’s available. Every little wildlife
reserve has a cache
to find and there are about 100 in a 30km radius of Durban
with more being added each week. You log your progress on the website
and you
are encouraged to start a little cache of your own. Geocaching is not
just
local, it’s worldwide. We have discovered so many beautiful
areas around Durban
that we would never have seen if it was not for Geocaching. The way it
works is
you register and then get access to the database and downloadable
waypoints.
You take something with you to replace what you take out of the cache
so that
there is always something for the next person to find. Some people are
happy to
just log the cache. Pack a picnic and make it a day to remember. Geocaching is
not Amateur Radio related but if you run APRS while you are hunting a
new
Amateur activity could appear.
Radio depends on propagation and in order to use the all the
information available you need to have a basic understanding of how it
all works.
In the earth’s atmosphere, particularly a region extending
from a
height of about 50 km to over 500 km, molecules are ionised by
radiation from the Sun to produce an ionised gas. This region is called
the ionosphere. Ionisation is the process in which electrons, which are
negatively charged, are removed from (or attached to) neutral atoms or
molecules to form positively (or negatively) charged ions and free
electrons. It is the ions that give their name to the ionosphere, but
it is the much lighter and more freely moving electrons which are
important in terms of high frequency (HF: 3 to 30 MHz) radio
propagation. Generally, the greater the number of electrons, the higher
the frequencies that can be used.
During the day there may be four regions present called the D region,
50 to 90 km, E region, 90 to 140 km, F1 region, 140 to 210 km and F2
region, over 210 km. During the day, sporadic E is sometimes observed
in the E region, and at certain times during the solar cycle the F1
region may not be distinct from the F2 region but merge to form an F
region. At night the D, E and F1 regions become very much depleted of
free electrons, leaving only the F2 region available for
communications; however it is not uncommon for sporadic E to occur at
night. Only the E, F1, sporadic E when present, and F2 regions refract
HF waves. The D region is important though, because while it does not
refract HF radio waves, it does absorb or attenuate them.
The F2 region is the most important region for high frequency radio
propagation because it is present 24 hours of the day; its high
altitude allows the longest communication paths, it usually refracts
the highest frequencies in the HF range. The lifetime of electrons is
greatest in the F2 region which is one reason why it is present at
night. Because the F1 region is not always present and often merges
with the F2 region, it is not normally considered when examining
possible modes of propagation.
If you would like to read more follow the Introduction to HF
Propogation in PDF format on the IPS Space and
Radio web site.
Sunday
Bulletins Every
Sunday morning following the S.A.R.L. Bulletin (Afrikaans 08H15 and
English 08H30), the Durban Amateur Radio Club presents a bulletin of
news and information (at 08H45) to keep members and interested
listeners up to date. 145.650Mhz duplex is the prime
frequency with a relay on 7.058MHhz in the 40m band. This bulletin is
re-broadcast every Sunday evening at 18H00 only on 145.650Mhz, Thanks
to OM Jimmy ZR5Z. and is followed by an evening of interesting
conversation.
Ham
Magazine
Ham Magazine follows the DARC bulletin at approximately 09H00. Ham
magazine is an interactive program run so as to include you, as an
active participant not just a listener. Take advantage of the program
and participate. The lineup also consists of the following
inserts.