SARL NEWS – SUNDAY 19 DECEMBER 2010
You are listening to ZS6SRL, the official radio station of the South African Radio League, the national body for amateur radio in South Africa, with a news bulletin every Sunday at 08:15 CAT in Afrikaans and at 08:30 CAT in English. To listen to a web stream, visit www.sarl.org.za, click on 'ARMI' and follow the links. PLEASE NOTE: for audio via Echolink, connect to ZS0JPL-R.
You can download this bulletin and previous ones from www.sarl.org.za and also subscribe to receive future bulletins by e-mail.
Your newsreader this morning is (name), (call sign), on 145,725 and 7,066 MHz from Pretoria, with relays on 7,066 and 3,695 MHz SSB. (Other news readers change as applicable).
SILENT KEY
It is with regret that it has to be announced that the key of Vernon Short, ZS1KS, became silent on Sunday morning, 12 December. Vernon had a long bout with Alzheimer’s disease and other problems. Our sincere sympathy with his wife Jessie, children, stepchildren, other relatives and friends
(PAUSE)
In the news today:
MONITORING SPACE WEATHER NOW A SERIOUS BUSINESS
MORE ABOUT LICENCE FEES
100 mW SIGNAL ON 8,970 kHz HEARD OVER 2 873 km
You are listening to ZS6SRL. Stay tuned for more details on these and other important and interesting news items.
MONITORING SPACE WEATHER NOW A SERIOUS BUSINESS
For Lee-Anne McKinnell, ZS2LAW, acting Managing Director of HMO, the launch of the Space Weather Centre at the Hermanus Magnetic Observatory is a four year dream come true. "It started with our application to be internationally recognised as the space weather warning centre for Africa. Although there are space weather scientists in other parts of our continent we are the only space weather warning centre", she told SARL News.
Delivering the opening address on 10 December 2010, the Minister of Science and Technology said that the launch of the Space Weather Centre speaks directly to South Africa's space science and technology 'grand challenge'. "This Centre will contribute essential information for global space science and technology, as well as forecasts and predictions to protect our growing and future satellite industry. More specifically, it will provide a service to the Earth observation, communications, navigation, defense and engineering sectors."
The Space Weather Centre will contribute towards other grand challenges, such as the Energy Security grand challenge, through its potential to develop a skills base and stimulate interest and desire among young people to take part in science and technology.
This project will position our country as a leader in Space Weather for the African continent, allowing for the development of projects that will create parallel initiatives between different African countries, and provide us with a leading focus area for joint collaborations.
“There is already a possible Space Weather satellite collaboration between India, Brazil and South Africa, which will proceed in the context of the IBSA Space Weather satellite", the Minister said.
"We are working closely with African Space weather scientists who will contribute data to us and in return we will provide space weather information which will assist them with their research," Lee-Anne McKinnell said. "The data that we will produce from their input and what comes out of our centre will help us with global space weather conditions. The other 12 regional warning centres come together to present data covering their area and we are working to do that for Africa”.
MORE ABOUT LICENCE FEES
ICASA is aligning its licence period with its financial year which runs from April to March. Radio Amateurs will receive an account for R6,75 which will cover January to March. During March an account for the period 1 April 2011 to 31 March 2012 will be mailed. Please pay the right amount on the account and wait for the account to arrive. Repeater and beacon accounts will be treated like wise and the amount charged will cover January - March 2011.
2011 CONTEST MANUAL NOW AVAILABLE ON THE WEB
The 2011 SARL contest manual is now available on the web. To download the manual, which is in PDF format, go to the contest section of the web or click on the link on SARL TODAY on the home page. The manual previously known as the blue book has been completely revised and upgraded and is a must have for anyone planning to participate in contests. It is yet another free service for radio amateurs from the SARL.
EMERGING TECHNOLOGY
100 mW SIGNAL ON 8,970 kHz HEARD OVER 2 873 km
The very low frequency transmissions by DK7FC on 8,970 kHz have been received at a distance of 2 873 km by 4X1RF in Haifa, Israel. Reception at these super low frequencies within the human audio hearing range requires ground rod antennas, low noise preamps and sophisticated decoding software. None the less, the fact that DK7FC's 100 milliwatt of effective radiated power was copied and recorded by 4X1RF at this great a distance indicates that transatlantic amateur VLF reception may indeed be possible in the very near future.
According to DL6QA in a tutorial published by the DARC, the very low frequency part of the radio frequency spectrum (VLF, 3 to 30 kHz) is characterized by a low attenuation rate, high phase and frequency stability, and high signal to noise ratio. Therefore, VLF radio propagation is used for many practical applications, e.g. frequency standardisation, clock synchronization, radio navigation beacons and reliable long-distance radio communications.
VLF waves can also penetrate water to a depth of roughly more or less 10 m to 40 m, depending on the VLF frequency employed, on the salinity of the water as well as on the temperature of the water. VLF is also used for very long-distance radio communications with submerged submarines near the surface.
Commercial VLF radio stations mainly apply very high power transmitters ranging from 5 kW to 500 kW or more. Due to the excellent ground propagation properties of VLF when transmitted vertically polarized and the very long wave length, all transmitters operate with very high antenna towers. Ground wave propagation is effected by the ground conductivity and the dielectric constant of the terrain. At 10 kHz the depth of penetration of VLF radio energy into the ground can be between 2,5 m to 150 m. The ground conductivity and the dielectric constant depends on the surface over which the ground wave propagates ( e.g. sea water - fresh water - dry, sandy flat coastal land - marshy, forested flat land - mountainous hills up to 1 000 m - cities - etc.).
Because of the low bandwidth available in the VLF band from 10 kHz to 30 kHz it is not possible to transmit audio signals, therefore most messaging is done with alphanumeric data at very low bit rates.
There is a large group in Europe studying VLF. Is anyone interested in starting a group in South Africa? Hannes Coetzee, ZS6BPZ, recently put out a call for amateurs to join him in experimenting on 137 kHz, a VLF band soon to be available to South Africans. Drop a line with your contact details to armi@sarl.org.za with VLF in the subject line.
HF PROPAGATION
Sorry but we have no update today, but we believe that there will be no drastic change from the conditions prevailing at present. However, go and have a look at www.spaceweather.co.za for the latest information.
DIARY OF EVENTS
31 December – Closing date for submission of logs for the PEARS HF QSO Party to contest@pears.ham-radio-op.net;
31 December – Closing date for submission of details for membership of the SA AMSAT satelliet team to saamsat@intekom.co.za;
20 January 2011 – Closing date for submission for application for the May 2011 RAE bursaries; visit www.amateurradio.org.za for application forms;
20 January - Closing date for submission of proposals and synopsis of papers for 2011 SA AMSAT Space Symposium to saamsat@intekom.co.za;
30 January 2011 - Closing date for phase 1 of the construction competition.
SARL News invites clubs and individuals to submit terms of interest to radio amateurs and shortwave listeners. Submit news items - if possible - in both English and Afrikaans to www.sarl.org.za/newsinbox.asp, not later than the Thursday preceding the bulletin.
The SARL also invites you to listen to Amateur Radio Mirror International every Sunday morning at 10:00 CAT on 145,750 MHz in the Pretoria area, with relays on 7 082, 7 205 and 17 560 kHz. There is also a podcast by ZS6RO. For a web stream and Echolink by ZS6FCS, visit www.sarl.org.za , click on 'ARMI' and follow the links. A repeat transmission can be heard on Mondays at 22:05 CAT on 3 215 kHz. Sentech sponsors the ARMI transmissions on the non-amateur frequencies.
Halt, don’t switch off, here follows the last item in today’s bulletin, and it comes from DFennis, ZS4BS, the President of the SARL:
“The year 2010 is drawing to a close and many SARL members are on holiday and spending quality time with their families and loved ones. We think back over the year and remember many highlights in the SARL calendar and also at club level. We must also pause and think of those of our friends who became silent keys during this year.
What does 2011 hold in for us? Early in the new year, the new radio regulations will be promulgated, in April the SARL National Convention will be held in the Vaal Triangle and in August, the SARL will host the 22nd triennial General Conference of Region 1 of the International Amateur Radio Union, the first such conference on the African continent.
On behalf of the Council of the SARL, I would like to wish you and your family an very Blessed Christmas and may 2011 be filled with good health and success. To our Jewish radio amateurs, I wish you Happy Hannaukah and to everybody I wish happy holidays”.
This from Dennis, ZS4BS, but to you also many thanks and best wishes to you and your family from all of us.
You have listened to a bulletin of the South African Radio League, compiled by George, ZS6NE.
Thank you for listening, 73.
/EX
