Well, the death toll after Myanmar’s double earthquake last week stood at 3145 on Friday, but there are another 4000 or so souls unaccounted for, so this is not the end of the tragedy. Assistance has been slow in coming to Myanmar, and the rubble of many buildings has not yet been removed, so sadly the numbers are going to rise. Rescue teams continue to struggle to clear debris as the chances of finding any more injured but living victims decrease.
Riaan Greeff, ZS4PR, Regional Director for HAMNET in the Free States reports that The 30th SASOL Marathon scheduled and planned for 29th March 2025 was a huge success for both the Sasolburg Athletics club and the Sasolburg Radio club.
The Sasolburg Athletics club called for the radio support from the Sasolburg radio club. The marathon event is a large event and leads to qualifying times towards the Comrades every year. And as happens every year, the seriousness of the call escalates to HAMNET being approached.
23 radio amateurs from three provinces went to Sasolburg on 28 and 29 March.
Gideon ZS4GJA was leading the logistical planning of this event, but due to a severe infection after a recent knee operation, had to withdraw medically and be booked in to a local hospital for an emergency procedure to address his leg.
Riaan, ZS4PR, HAMNET Director Free State, then took the reins to ensure the volunteers are catered for and the arrangement Gideon had in place could be adopted.
Brian, ZS6YZ, the newly appointed National Director HAMNET, an active HAMNET leader for several years, also attended the race. Family works together, and his daughter Anja ZS6SJC was also present. Like father like daughter…
The Gauteng and Limpopo members drove though on Friday afternoon and by Saturday morning 4am everyone was in attendance, ready to be deployed to strategic points all over Sasolburg.
Leon, ZS6LMG and Linda ZS6LML took responsibility to lead the athletes, and after the event, remarked that lead athletes are way more taxing than leading cyclists. It was a first for this experienced couple.
Ruan ZS6RFC and his wife Ilze-Mari ZS6IMF took the lead for the 10km group.
The route was manned by several HAMNET members, focused on reporting the condition of athletes, summoning ambulance services, and giving feedback to the JOC, manned by Riaan ZS4PR, Jaco ZS6JCO and Wim ZS6WIM. Inter-provincial people sitting in the same JOC does allow for excellent experiential learning.
Talking of learning and training, Pro-Ethnos, a fire brigade first responder training team lead by Jurie ZS6RIT from the West Rand was also called to use this event as a training opportunity. Riaan instructed and allowed the young ladies Maryka ZS6MVS, Duemarie Swart and Nia Nel with their K9, Noala, to practice their communication skills by placing them in one of the more challenging areas in Sasolburg. They had to relay their messages to a central person, who then relayed the messages to the JOC. It was the first time they tried to work radio this way, and fared well, with many lessons learned.
By 13:00 the event was over, and the last athletes safe and accounted for.
Dolf Binneman, Chairman of the Sasol Marathon and Sasolburg Athletics club complemented the HAMNET team of radio amateurs for their professional and effective support they provided. All his water-points and safety staff gave him positive feedback where HAMNET was involved to assist.
The Sasolburg and Vaal area have excellent radio repeater infrastructure in place. UHF DMR and 2m FM repeaters were used as the main communication channels, and APRS via the digital packet repeater network provided real time tracking of the ham activities, the ambulances and the back marker vehicles.
Riaan thanks his team for a job well done, and I thank Riaan for the fine report.
Writing on camras.nl, a group of radio amateurs report that, on 22 March 2025, they used the Dwingeloo Radio Telescope successfully to bounce a radio signal off the surface of Venus. At the time, Venus was in its closest approach to Earth at about 42.000.000 km. Such a conjunction happens when Venus is between the Sun and the Earth, and happens approximately every 580 days.
‘Earth-Venus-Earth’ (EVE) bounces were extensively performed in the 60’s and 70’s to make radar images of Venus. More recently, in 2012, the Arecibo telescope in combination with the Green Bank telescope made a very detailed map of Venus. The first and, until now, only amateur EVE was achieved in 2009 by AMSAT-DL from the 20m Radio telescope at the Bochum Observatory (Sternwarte Bochum).
The Dwingeloo telescope was commanded to transmit a 278 second long tone at a frequency of 1299.5 MHz. Since the light travel time to Venus and back was about 280 seconds, they could receive the reflection of their own signal afterwards. They repeated this cycle four times.
While Dwingeloo received its own echo, the Stockert radio telescope, operated by Astropeiler Stockert e.V., also successfully received Venus’ echo of Dwingeloo’s signals. The receptions in Stockert were stronger than those received in Dwingeloo, since the Stockert receiving chain is a bit more sensitive.
The data analysis consists of correcting the received data for both the expected Doppler shift and the rate of change of this Doppler shift due to the rotations and relative motions of Earth and Venus. After channelizing the received signal in 1 Hz frequency bins, the echo of the transmitted signal should fall exactly in the predicted bin.
The preliminary analysis already shows a 5.4 sigma detection for Dwingeloo-Venus-Dwingeloo, an 8.5 sigma detection for Dwingeloo-Venus-Stockert, and a 9.2 sigma detection when combining the signals of Dwingeloo and Stockert.
They were planning to send complex modulated signals to perform more analysis on the correlations between transmitted and received signals. Unfortunately the transmitter, mounted in Dwingeloo’s focus box for the occasion, started failing after four successful transmissions. They therefore postponed the other experiments to the next Venus conjunction in October 2026.
In the preparation for this experiment, they collaborated with the Deep Space Exploration Society, who were also preparing an EVE experiment of their own, and the Open Research Institute. During the day of the experiment, they had a lot of help from present CAMRAS volunteers. A big thanks also goes to the volunteers of Astropeiler e.V. for observing with the Stockert telescope.
And thank you to camras.nl for that report.
This is Dave Reece ZS1DFR, wondering whether Venus is full of little pits from having radio signals bounced off her continuously, and reporting for HAMNET in South Africa.