SARL NEWS - SUNDAY – 17 AUGUST 2008
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 transmitted every Sunday at 08:15 CAT in Afrikaans and at 08:30 CAT in English. To listen to a webstream, visit www.sarl.org.za, click on ARMI and follow the links for details. PLEASE NOTE! For audio via Echolink, connect to ZS0JPL-R.
You can download this and previous bulletins from www.sarl.org.za and 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 28,325, 14,235, 10,130, 7,066 and 3,695 MHz SSB, as well as 51,400, 438,825 and 1 296 MHz FM in the Pretoria area. (Other newsreaders please change to suit).
SILENT KEY
It is with regret that we have to announce that the key of Willie, ZS6BZ, became silent recently, further particulars are unknown. We extend our condolences to his relatives and friends.
(PAUSE)
In the news today:
TROPO DUCTING CONTACT BETWEEN ZS2GK AND FR5DN ON 2 METRES SHOWS THAT PERSEVERANCE PAYS OFF
PLT STANDARDS - SOUTH AFRICA REJECTS CALL FOR RELAXATION
SARL MEMBERSHIP RENEWAL DOING WELL
WHEN IS ET CALLING HOME?
SPREAD SPECTRUM - LEARN MORE ABOUT IT AT THE RTA
You are listening to ZS6SRL. Stay tuned for more detail on these and other important and interesting news items.
TROPO DUCTING CONTACT BETWEEN ZS2GK AND FR5DN ON 2 METRES SHOWS THAT PERSEVERANCE PAYS OFF
Glenn Kraut, ZS2GK, in Mqandulin, a village in the Eastern Cape, made an historic contact with FR5DN on Reunion on 2 metres over a distance of 2 875 km.
On Tuesday 12 August at 10:40 local time ZS2GK heard the Reunion beacon at signal strength 1. He phoned Phil, FR5DN, on Reunion who said that he was racing home from work and would be there in 30 mins. He was unfortunately held up in heavy traffic. By the time he arrived home the band had dropped out.
On Wednesday evening ZS2GK went to bed at about 22:30 local time leaving the rig on and antennas pointing towards Reunion. He woke up at 02:15 and heard a beacon. The signal was very weak and he went back to bed. Scarcely one hour later he heard a stronger beacon signal. It was perfect copy on the CW reader.
Glenn called Phil on his cellphone, switched the linear and pre-amp on and logged a SSB QSO and FM QSO on 144,200 and 144,400 at 03:39 CAT with signal reports of 5/6 both ways. "We spoke for about 20 minutes. I also tried to access the Reunion repeater without any luck", he told SARL news. "There was no QSB on the SSB signal but a bit of fade into the noise on FM." Listen to the QSO on www.sarl.org.za.
Glenn uses 4 x EX6OB 2 m, 9 element antennas built by ZS6OB on an H Frame at 2 m above the roof. Power used was 400 W on SSB and 200 W FM giving an ERP of about 28 100 W on SSB. On the receive side he uses a GasFet pre-amplifier, a perquisite for all serious VHF work
VHF and UHF radio waves can propagate over the horizon when the lower atmosphere of the earth bends, scatters, and/or reflects the electromagnetic fields. These effects are collectively known as Tropospheric propagation, or tropo for short.
The most well-known form of tropo is called bending. Air reduces radio-wave propagation speed compared with the speed in a vacuum. The greater the air density, the more the air slows the waves, and thus the greater is the index of refraction. The density and index of refraction are highest near the surface, and steadily decrease with altitude. This produces a tendency for radio waves at very-high frequencies to be refracted toward the surface. A wave beamed horizontally can follow the curvature of the earth for hundreds of kilometres.
A less common, but often dramatic, form of tropo is called ducting. This occurs when there is a defined, horizontal boundary between air masses having different densities. When a cool air mass is overlain by a warm air mass, as is the case along and near warm fronts and cold fronts, radio waves at VHF and UHF are reflected at the boundary if they strike it at a near-grazing angle from beneath (within the cooler air mass). Because radio waves are also reflected from the earth's surface, the result can be efficient propagation for hundreds or, in some cases, upwards of 1 600 km, as the waves alternately bounce off the frontal boundary and the surface.
According to Mike Bosch, ZS2FM, it is difficult to confirm whether it was tropo ducting or Sporadic E. Whichever the case, it is a great achievement. Well-done ZS2GK and FR5DN.
PLT STANDARDS - SOUTH AFRICA REJECTS CALL FOR RELAXATION
As reported last week, the SABS TC73 Electromagnetic Compatibility Committee met on Wednesday and discussed, amongst other, relaxation of PLT interference standards.
There has been a flurry of international activity to convince CISPR not to accept reduced standards when it meets later this Year. The SARL heeded the IARU request to lobby the local CSIPR representative to support the IARU's call to protect the HF frequency spectrum by setting standards that adequately defend the spectrum against harmful interference. The SABS TC73 committee accepted the SARL representative's proposal not to support the 18 dB relaxation unanimously with two abstentions. The South African CISPR delegate will table South African opposition to the relaxation proposal when CISPR meets in October.
The proposed hearing to discuss objections lodged against the proposed interim PLT regulations will still go ahead. There are some administrative issues to be finalised before ICASA can set a date.
SARL MEMBERSHIP RENEWAL DOING WELL
On Friday morning the SARL membership renewals for the 2008/2009 financial year stood at 1 034. Thanks to all who renewed promptly. There are still 2 and a half weeks left to benefit from the discounted rate of R305. If you have not already renewed do it now. Help us to get past the 1 1OO mark by next Friday.
All renewable or new subscriptions received before 31 August 2008 enjoy a discount. You only pay R305 and not the new fee of R320 which will be applicable from 1 September. Senior members pay only R184 if they remit by 31 August. After that date it will cost R200. For payment details contact Vee Antal on 011 675-2393.
All fully paid up members receive a 2008/2009 membership certificate. If you are not a member yet, join the SARL now and increase the power of our voice with the authorities.
WHEN IS ET CALLING HOME?
Join the INTECNET this evening (Sunday 17 August) at 19:30 when Paul Shuch, President of the SETILeague will be discussing the Search for Extra Terrestrial Intelligence.
The Search for Extra Terrestrial Intelligence is a scientific based activity that you can participate in by turning antennas skywards and search for that elusive signal that may have been sent by intelligence a long time ago.
Paul Shuch is an interesting speaker and promises participants in the Intecnet an interesting Sunday evening.
The Intecnet will also be broadcast by Radio Today in Gauteng on 1 485 kHz and channel 169 on DSTV audio bouquet.
SPREAD SPECTRUM - LEARN MORE ABOUT IT AT THE RTA
One of the many interesting presentations on the RTA programme is about spread spectrum. The journey from the Mathematic Theory of communications in 1948, by Claude Shannon, until today's Orthogonal Frequency Division Modulation Techniques has been a revolutionary journey. It has exceeded all previous communication developments, even those of the Spark transmitter and Radar. With noise levels increasing Amateur Radio will have to explore other modes. Spread Spectrum Techniques on both HF and VHF and UHF is one of the options.
The presentation by John Willescroft, ZS6EF, explains in every day language how spread spectrum works and the technical reasons why it will be the only way we will communicate in the future. His presentation includes some interesting practical examples.
The RTA - Radio Technology in Action is presented by the SARL at the National Amateur Radio centre at Radiokop on 13 September 2008 from 08:30 - 16:0.. Visit www.sarl.org.za for more details.
CONTEST NEWS
SARL HF CONTEST - PLEASE SEND IN YOUR LOGS
The SARL HF SSB contest was well supported and a large number of logs have been received. If you have not yet mailed your log, you still have until Monday to do so. All logs with 20 or more contacts will go into the lucky draw for the 2008 ARRL handbook.
CLUB NEWS
SANDTON ARC TO SPONSOR A NEW FUN AWARD
Sandton ARC is proud to announce that we will be sponsoring a new award as from 1st August 2008. The award is called ZS WAGS - Worked all South African Grid Squares - "Chasing Maidens".
Before you get the wrong impression, the "Maidens" referred to are Maidenhead grid locators!
South Africa is completely contained within 83 "grid squares," although some of these contain a very small piece of land.
The aim of this award is to make contact with a station located in each of the 83 grid squares.
Two awards are offered, the Hunter’s Award and the Activator's Award.
The Hunter's Award may be claimed from 25 grid squares upwards, eg: you can apply for ZS WAGS 25, ZS WAGS 50, ZS WAGS 60, and so on up to the magic number of 83.
To encourage amateurs to travel to the more remote or inaccessible grids, the Activator's Award can be claimed by an amateur who makes a minimum of 10 contacts from one of these less-amateur-populated grids.
The system is based on honesty and trust, and proof of contacts is not required. In addition, there is no cut-off starting date, so you may go back through your existing logbook to find all contacts, which qualify.
For more information go to the web site at www.zs6stn.org.za/zswags/, send an email to zswags@gmail.com to receive a copy of the rules, or call Peter, ZS6PHD, at 083 445 4634.
PRETORIA AMATEUR RADIO CLUB COMMITTEE
The Pretoria Amateur Radio Club held their AGM on 9 August 2008 and the following members were elected to the club’s committee:
Johan de Bruyn, ZS6JHB, Chairman;
Alméro du Pisani, ZS6LDP;
Craig Symington, ZS6RH;
Richard Peer, ZS6UK;
Graham Reid, ZR6GJR;
Doréén de Bruyn, ZR6DDB.
The remaining functions will be assigned at the next committee meeting. We thank the outgoing committee for their efforts and wish the new committee all the best for their new term of office.
PROPAGATION REPORT
Hannes Coetzee, ZS6BZP reports that the expected solar activity will be very low. The geomagnetic field is expected to be mostly at active to unsettled levels untill 20 August after which it will reach quiet levels till 3 September.
The expected Effective Sun Spot number for the coming week will be less than 5. DX conditions will generally be good to the North and poor in the general North-Westerly directions.
20 m will provide best opportunities for DX. There is a possibility of weak 20 m openings towards India from about 16:00 CAT. There is the possibility of weak 40 and 80 m openings to New Zealand at 20:00. Otherwise contacts with Australia and New Zealand will be very challenging. From 16:00 there may be 20 m openings towards Europe. Contacts with the USA are going to be very challenging.
10 MHz is looking promising late afternoon and after dark for the CW and digital enthusiasts.
Local conditions are going to be good on 40 m during the day time. 80 m may perform well during the mornings and late afternoons over the shorter distances, e.g. between ZS5 and ZS6. 30 m may perform well during the middle of the day between ZS6 and ZS1.
80 m is the frequency of choice in the evenings. With summer approaching it is now an excellent time to make those 80 m contacts for your WAZS before the thunderstorms and static start again . 160 m will also perform well during the evenings.
Remember that this is only a prediction and that HF always has the capability to surprise you, but you will never know unless you switch your rig on, listen and also call CQ.
Please visit www.spaceweather.co.za for further information.
DIARY OF EVENTS
17 August – INTECNET, that is tonight at 19:30;
30 August – East Rand Radio Club AGM;
31 August – Last day for subs at discount rates;
13 September – Radio Technolgy in Action at the National Amateur Radio Centre;
03 October – Young Ladies meet SA starts;
08 October – Set up a school station for Space Week activity.
SARL News invites clubs and individuals to submit news stories of interest to radio amateurs and shortwave listeners. Submit news stories if possible in both English and Afrikaans to www.sarl.org.za/newsinbox.asp not later than the Thursday preceding the bulletin date.
The SARL also invites you to listen to the programme Amateur Radio Mirror International, on the air every Sunday morning at 10:00 CAT on 145,750 MHz in the Pretoria area with relays on 7 082, 7 205 and 17 590 kHz. For the webstream and Echolink by ZS6FCS visit www.sarl.org.za, click on ARMI and follow the links. A repeat transmission can be heard Mondays at 21:00 CAT on 3 215 kHz. Sentech sponsors the ARMI transmissions on the non-amateur frequencies.
Today's South African Radio League news bulletin was compiled by George, ZS6NE.
Thank you for listening. 73.
