Within a span of seven hours on Friday morning early, the Sun unleashed two powerful X-class solar flares, disrupting high-frequency radio communications across parts of the Pacific, Australia, and East Asia. The bursts, rated X2.4 and X2.5, coming from Active Region 4419 on the sun, are the strongest in over two months and signal heightened solar activity as the current cycle nears its peak

This rapid succession, just seven hours apart, is unusual and points to a highly unstable magnetic configuration. Such events occur when complex sunspot magnetic fields suddenly release stored energy, sending intense radiation across the solar system within minutes of eruption.

NOAA and space weather agencies are tracking the magnetically unstable region responsible for the flares. Clusters of strong flares often precede larger solar events, and if future eruptions are accompanied by coronal mass ejections aimed at Earth, they could trigger geomagnetic storms. Such storms have the potential to disrupt satellites, GPS, and power grids, prompting heightened preparedness among infrastructure operators.

Thanks to MSN.com for this summary.

Brian ZS6YZ, our National HAMNET Director tells me that he and Willem ZS6WIM attended a National Disaster Management Strategic Indaba at Emperors Palace, in Gauteng on Tuesday 14^th April 2026.. The Indaba covered an update on the Review of the Disaster Management System and planned interventions to get Disaster Management back on track.

Here in South Africa our weather patterns are becoming more severe and with devastating impact on communities. Disaster management needs to step up their efforts to reduce the impact on the communities by helping them to be better prepared. One of the ways is to provide early warning of approaching severe weather.

At the meeting, one of our colleagues from the Gauteng Provincial Disaster Management Centre presented an update on the Early Warning System that is being planned, noting that there would be a meeting soon, to continue the quest to find a solution.

An early warning system work in two ways:

Firstly, the weather services needs to know that is happening on the ground. The weather forecasters have access to weather radar systems that can provide them with an understanding of where a storm is and how severe it may be. They also have knowledge from previous storms of what to expect. However, they do not know what is happening on the ground in real time. In other countries such as the US, there is a Skywarn System where radio amateurs are trained to be storm spotters and provide real time information from the ground on the effects of the storm that is being seen on the weather radar.

Secondly, there needs to be a way for the communities who may be severely affected to be warned so that they can take the necessary precautions prior to the storm approaching them.

There are various ways that this can be done, including using the cellular broadcast facilities that are built into the GSM systems to disseminate information. The Weather Services also have Impact Based Warnings WhatsApp groups where forecasters and Disaster practitioners can exchange information. But, what happens if the cellular systems are down? What will plan B or C be?  Are there other technologies that can be deployed to assist with early warning systems? 

The other challenge is that the Government has lost a tremendous amount of knowledge, expertise and skills over the years, and they now look to volunteer organisations to assist them in filling the gaps.

This situation provides opportunities for communications specialists from HAMNET who have a varied knowledge base and who understand the inherent weaknesses of communications systems, to be able to partner with disaster practitioners to explore solutions that do not depend on commercial infrastructure.

On Saturday afternoon 18 April 2026, a small group of HAMNET Gauteng members met at the equipment container at the Brakpan airfield to discuss the use of technology in emergency communications. Brian delivered the presentation “Using Technology to provide effective HAMNET emergency communications” that was first presented at the 2026 National Technical Symposium. A discussion then took place on the importance of not only focussing on amateur radio digital modes, but on all technologies that could be used to pass information in the event of an emergency or disaster, be it wireless, microwave link, or even satellite services like Starlink. It is important that the best available technology be used, backed up by layers of alternate solutions that could be deployed should the primary solution fail or not be available.

Thank you for this summary of the communications associated with weather and the way forward, Brian.

wbng.com reports that a historic radio tower in Binghamton was used to connect with others around the world yesterday to commemorate the birthday of one of the inventors of radio.

Happening on Saturday, April 25, members of the Binghamton Amateur Radio Association (BARA) talked to amateur radio operators around the world using the historic Marconi Tower at 45 Lewis St.

The event commemorates the birth of Guglielmo Marconi, one of the inventors of radio, and is held annually on the Saturday closest to his actual birthday.

BARA operated using the tower from 9:30 a.m. to 4 p.m. local time, reaching out to stations worldwide that were operating at other historic sites related to Marconi’s life and career. This event has been happening in Broome County annually since 2017.

Binghamton’s Marconi Tower is the last of four towers, two built in Binghamton and two in Scranton, that were put up by Marconi in 1913 as part of a pioneering experiment that first demonstrated radio-communication with a fast-moving vehicle, specifically a train traveling between Scranton and Binghamton.

This is a final reminder now to you all to appoint a proxy for the Annual General Meeting taking place next week Saturday the 2^nd May. Please note that the SARL website will be offline on Wednesday the 29^th for scheduled maintenance, so, if you want to download that proxy form, do it today! Please send it back to the secretary by midnight on Wednesday. And note the SARL office will be closed all of the coming workdays this week, so you cannot direct enquiries to Admin before the AGM. Please be proactive.

This is Dave Reece ZS1DFR, wishing the attendees a useful AGM and a pleasant banquet next Saturday, and reporting for HAMNET in South Africa.

By 16 April at 03:00 UTC, Tropical Cyclone SINLAKU’s centre was located over the ocean approximately 144 km west of Alamagan Island, with maximum sustained winds of 185 km/h.

According to the Federal Emergency Management Agency (FEMA), a total of 1 080 people remain evacuated in 16 evacuation centres, 320 in the Northern Mariana Islands and 760 in Guam. Additionally, FEMA and media report power and water outages, particularly on Guam, Saipan, Rota and Tinian.

Over the next 48 hours, heavy to very heavy rainfall, strong winds and storm surges are forecast for most of the Northern Mariana Islands and Guam. A Typhoon Warning remains in effect for Rota, Tinian, Saipan, Alamagan, Pagan and Agrihan islands.

The US Coast Guard News advised mariners of outages in VHF radio communications coverage in the vicinity of Guam, Rota, Saipan and surrounding areas in the Commonwealth of the Northern Mariana Islands on Wednesday.

Mariners should anticipate reduced reception and transmission capabilities that may potentially impact distress and safety communications.

Remote fixed facility tower outages have impacted coverage around Guam, Rota, and Saipan, extending from coastal areas to 20 nautical miles offshore.

Joint Rescue Coordination Center Honolulu watch-standers issued a safety marine information broadcast and SafetyNET broadcast informing mariners of outages.

Meanwhile, Malaysia, Indonesia, Panama and Haiti are also all experiencing severe weather and flooding.

And you can take it from me that winter officially started on Friday the 17^th in the Western Cape. A powerful cold front arrived in the early morning, with lots of rain, with a large amount of cold Antarctic air behind it, resulting in snow being experienced in the Matroosberg mountains, and, according to snowreport.co.za, forecast for the peaks of Franschoek, Paarl, Worcester, De Doorns, Montagu, Ceres, Tulbagh, the Koue Bokkeveld and the Cedarberg, as well as the Swartberg mountains, for the weekend. Time for the thermal underwear indeed!

Meanwhile, the measles epidemic in children in Bangladesh is spreading, with 19161 cases hospitalized and 166 deaths reported. 22 million doses of vaccine are being distributed, and 943000 children under the age of 5 have been immunized so far. Vaccinate your children, people!

For those of you still suffering from the heat trapped inside your closed car parked somewhere, you’ll be excited to hear that a transparent radiative cooling film technology that dissipates heat directly to the outside without consuming electricity has been developed to reduce vehicle overheating during summer. The technology was validated through real-vehicle experiments conducted under diverse conditions—including different countries, seasons, and both parking and driving scenarios—and demonstrated the ability to lower cabin temperatures by up to 6.1°C and reduce cooling energy consumption by more than 20%.

The website phys.org says that Seoul National University College of Engineering announced that a research team has designed and fabricated a large-area Scalable Transparent Radiative Cooling (STRC) film applicable to vehicle windows. Through real-vehicle evaluations conducted under various climatic and driving conditions, the team demonstrated both energy-saving and carbon reduction effects.

This research was published online on February 4 in the journal Energy & Environmental Science.

Vehicles exposed to solar radiation in summer experience rapid increases in cabin temperature, resulting in substantial cooling energy consumption. Conventional automotive Low-E coatings and tinting films can partially block incoming solar radiation but fail to dissipate effectively heat already accumulated inside the vehicle, thereby limiting their cooling performance.

Radiative cooling technology, which has attracted attention as an alternative, simultaneously blocks incoming solar energy and emits internal heat to the outside, enabling passive cooling without electricity. However, most previously developed radiative cooling materials are opaque, making them unsuitable for application to vehicle windows, which are the primary entry points for heat.

To overcome this limitation, the research team developed a large-area transparent radiative cooling film with a multilayer structure that maintains over 70% visible light transmittance, reflects near-infrared solar radiation, and emits heat from the vehicle interior in the mid-infrared range. This film suppresses temperature rise inside the vehicle without consuming electrical energy and reduces the time required to reach thermal comfort, thereby minimizing energy consumption in electric vehicles.

Real-vehicle experiments conducted across different climatic regions—including Korea, the United States, and Pakistan—and under varying conditions such as summer and winter, as well as parking and driving scenarios, confirmed that vehicles equipped with the STRC film consistently maintained lower cabin temperatures under all conditions.

And in bad news for the vapers of the world, phys.org also reports that a study published in Analytical and Bioanalytical Chemistry by University of Technology Sydney (UTS) researchers showed that even short-term vaping at exposure levels below typical daily human use resulted in measurable accumulation of toxic metals in lung tissue—including lead, copper and nickel.

Lead researcher Dr. Dayanne Bordin, a lecturer in analytical chemistry, said the pre-clinical study provides the first evidence that e-cigarette aerosols include metal-containing (organometallic) species, including those associated with tin and mercury—forms that are often more bioavailable and biologically reactive than inorganic metals.

“From a risk perspective, the findings reveal under-recognized hazards associated with vaping,” she said.

“Metal emissions and their biological effects are rarely incorporated into current safety assessments or public understanding. Unlike cigarettes, which are relatively consistent products, e-cigarettes and devices are often manufactured with poor quality control involving materials and components with unknown toxicological relevance.

“The metal profiles observed are consistent with emissions from heating coils and electrical components, identifying the device itself as a critical source of exposure and highlighting important gaps in how vaping risks are evaluated.”

Dr. Bordin explains this is important because many people believe vaping carries less risk than conventional cigarettes. This perceived reduction in harm, along with misleading marketing campaigns, has contributed to the rapid uptake of e-cigarettes globally, particularly among younger demographics. In Australia, for example, e-cigarette use among young adults increased from 5.3% in 2019 to over 21% in 2023, with a similar rise in adolescents.

“Our findings challenge the assumption that e-cigarettes are safer and show how critical it is to review current vaping regulations, which should be expanded to include device-derived emissions, not just the e-liquid composition,” she said.

“Vaping can deliver toxic metals directly into the lungs, even after short-term use. This information is important for anyone considering vaping, especially young people, because these metal exposures are largely invisible and rarely discussed.”

Thank you to phys.org for this alarming report.

I hope I don’t need to remind you that increased levels of heavy metals in the body and the brain are associated with an increased risk, at an earlier age, of dementia.

This is Dave Reece ZS1DFR, having given up smoking in 1972, and thankfully never having tried vaping ever, and reporting for HAMNET in South Africa.

On Friday the 10^th, the Global Disaster Awareness Coordination System (GDACS) announced a Red Alert for Tropical Cyclone SINLAKU, travelling from South-east to North-west, and threatening the islands of Guam and the North Mariana Islands. With maximum wind speeds of 194 km/h, and as a category 3 hurricane, it was threatening 180000 people in its path. The maximum effect is expected to be felt on Monday the 13^th and Tuesday the 14^th of April, as SINLAKU first makes landfall over Guam.

In last week’s bulletin, I promised to share the other half of the report on the SASOL Marathon of 28^th March, received from Riaan Greeff ZS4PR, Divisional Director for HAMNET in the Free State. He wrote further:

”HAMNET acquired “Single Frequency Repeater” (SFR) Digital Mobile Radio (DMR) technology in the form of 3 repeaters and 20 hand radios for the race.  The principle of SFR is to make use of the 6.25kHz channels with 2 alternating timeslots and transmit AND receive simultaneously on the two RF channels at either timeslot 1(TS1) or timeslot 2 (TS2). 

“DMR is a digital radio mode utilizing Time Division Multiple Access (TDMA) modulation.  This feature allows a repeater network to be deployed systematically into areas of need fast and effectively. Only one frequency is used, so no cavity filters are needed.  The hand/portable radios are set to follow TS1 and TS2 in the two channels and seamlessly switch between simplex and repeater mode as the signal’s strength indicator is evaluated in real time.

“The Technical team set up three repeaters in a triangle around the route. This worked well. However, when all 15 radio users were active it became troublesome to decode the DMR signals.  On investigation, it was found that the two 6,25kHz TS1 and TS2 signals were creating heterodyning for the receiving radios.  The better way to set up three or more SFR units would be to deploy the repeaters in a straight line and not in a triangle/circle/looping arrangement.

“Why is this important for HAMNET? The Barberton aeroplane accident in 2025 highlighted the need to set up repeaters quickly and easily at local high sites.  A SFR is extremely portable, and an ordinary ham can set it up in 10 minutes. The handheld radios are issued to specialists on the ground to do their work. HAMNET provides the infrastructure to deploy the hand held radio capabilities with the SFR repeaters. SFR allows effective radio signal selection management and relays signals autonomously. “

Google tells me that “a Single Frequency Repeater is a digital radio device that extends communication range using only one frequency, rather than the two required by traditional repeaters. It works by using Time Division Multiple Access (TDMA) to receive a signal on one time slot and simultaneously retransmit it on the other time slot within the same 12.5kHz channel, eliminating the need for a duplexer and allowing for cost-effective coverage extension.

“The repeater receives a snatch of data in time slot 1 and immediately forwards it in time slot 2 (that is: 60-90 milliseconds later), enabling direct mode operations to extend range without needing to change frequencies, as is used in analogue communications. The timing is so fast that the listener cannot discern the very short breaks in the received signal. Effectively, the repeater is alternating between receiving and transmitting the signal every 60-90 milliseconds but on the same frequency.”

Furthermore, if the received signal from the sending station is strong enough, as monitored in the Received Signal Strength Indicator algorithm of the repeater, it will not be repeated, but allowed to pass directly. So the transmission proceeds in the least complicated manner.

Thank you, Riaan, for telling us of your experiments with this technology.

If you have ever worried about the efficiency of your car’s brakes, spare a thought for the Orion capsule astronauts, as they came in to splashdown at about 2am our time on Saturday morning. While still approaching our atmosphere, they were travelling at 11km per second, about 40000km/hour, 40 times faster than a typical passenger jet.

After smashing through the Earth’s atmosphere, travelling at more than 30 times the speed of sound, the spacecraft had to slow to a safe speed for landing.

As it crashed into the top of the atmosphere, the craft created a shockwave that saw the surrounding air reach temperatures of 10,000C or more. To keep humans inside safe, Orion’s heat shield is made of Avcoat, a mixture of silica, epoxy and resins that NASA also used for the original Apollo missions to the Moon.

After the initial shockwave, the heat shield experienced temperatures of around 2,700C as the crew module plummeted through the atmosphere on re-entry. The coating of 200 Avcoat tiles is just a few inches thick and is designed to burn away, transferring heat away from the spacecraft.

The astronauts then fell 122000 metres through Earth’s atmosphere and were completely out of communication with mission control as superheated plasma around the capsule disrupted radio signals.

During this descent, the crew experienced 3.9G’s, or nearly four times normal gravity. This means their bodies felt four times heavier than normal. Astronauts had to train to withstand these high G-forces on re-entry. As Orion slowed it started to cool and radio communications resumed.

At around 11000 metres, around the cruising altitude of a passenger plane, Orion opened its first of two sets of parachutes designed to slow it for the final landing. The main chutes opened at around 1800 metres, and at 900 metres they fully opened for a gentle landing.

After splashdown, a system of five airbags on top of the capsule inflated, turning Orion right side up if the capsule landed upside down.

Thank you to mirror.co.uk for that summary of events.

Finally, a reminder to all HAMNET members who are unable to attend the SARL Annual General meeting from the 1^st to 3^rd of May, to give your Proxy to vote to a HAMNET member near you who is attending. Download the Proxy Form at https://forms.gle/GeWRwJnT1aSzyZPw9, fill it in, and return it as instructed on the form. Thank you.

This is Dave Reece ZS1DFR, wondering if I should install a deployable parachute on the back of my little car to guarantee my ability to stop, and reporting for HAMNET in South Africa.

GDACS reports that a strong offshore earthquake of magnitude 7.8 M at a depth of 35 kilometres occurred in the northern Molucca Sea, between the islands of Sulawesi and Halmahera in Indonesia, on 1^st April at 22:48 UTC (07:48 local time). The epicentre was located 126 km west-north-west of Ternate City, on Ternate Island, North Maluku Province. A tsunami warning for a wave of about 2 metres was issued, but later retracted.

At least 18 aftershocks were recorded in the area, with magnitudes ranging from 4.4 M to 6.2 M.

USGS PAGER estimates that about 209 000 people were exposed to strong shaking and 2.1 million to moderate shaking. One fatality had been recorded by Friday the 3^rd.

In passing, on the 3^rd of April, GDACS reported on no less than 60 earthquakes of magnitude 4.5 or greater round the world in the previous 24 hours. The earth was a very unsettled place on Thursday the 2^nd!

Riaan, ZS4PR, Divisional Director for HAMNET in the Free State has sent me two reports on the SASOL Marathon of the 28^th March, at which Div 4 and Div 6 amateurs assisted. I will keep the second half of the report over to next week, but here is an interesting look at an unexpected complication of such a race. Riaan writes:

”At the 31st SASOL Marathon, the Sasolburg Radio Club’s radio caravan was deployed at the D.P. de Villiers Stadium. In this communication centre, the event communication between the field operators, the ambulance services, and the logistics manager of the Sasolburg Athletics club came together. The set-up of the APRS tracking, Single Frequency Repeater (SFR) and 2m VHF repeater with the GSM SIP phone system in the caravan took place on Friday 27^th March. 

“By the time that the estimated 3500 athletes with their families/supports had arrived, (from 4am Saturday morning), the cell phone networks (all GSM services) became overwhelmed and started collapsing in the area around the stadium between 5 and 7am.  The CPF and the ambulance services using PTT-apps and WhatsApp and Zello could not communicate to their teams.  ONLY the RF-APRS tracking on 144.800MHz, the 2m FM repeater on 145.6875MHz and the SFR network (432.525MHz) were able to send signals to the logistics team who were issued the SFR handheld radios.  APRS trackers using GSM such as APRSDROID could not report positions.

“The update of the tracking maps in the Club caravan could only happen on the computer that had pre-loaded maps for the race. ALL online/internet (server) software failed to provide live and real time tracking updates for the 2-hour window the mass runners were in the area of the stadium.

“Interestingly, this lack of GSM cell service was observed to move with the main crowd of athletes as they ran through the town.  This caused localised GSM outages to the town centre and houses as the crowds moved passed.  Amateur radio infrastructure was 100% available where the GSM services failed.”

The race appears to have flowed peacefully, says, Riaan, and all amateurs from the Sasolburg area and Gauteng South are thanked for their help.

Thanks Riaan for that news. Good to know that amateur radio could hold its head up high!

Next week I’ll mention Riaan’s description of the Single Frequency Repeaters in more detail. Fiendishly cunning!

global.chinadaily.com reports that the world’s most powerful cargo drone, built by China North Industries Group Corp, conducted its first flight on Tuesday in Zhengzhou, the capital of Henan province.

A prototype of the Norinco Luca, also known as the Changying-8, took off at 9:30 am from Zhengzhou Shangjie Airport and remained airborne for about 30 minutes before landing at the same site. According to Norinco UAS, the drone’s developer and a Beijing-based subsidiary of China North Industries Group Corp, engineers checked the model’s flight control, avionics, electronic and power systems and achieved the desired results.

In a news release, it said that the entire flight had been controlled by the aircraft’s intelligent systems and monitored by human controllers.

The Norinco Luca is 17 meters long with a wingspan of 25 meters, and has a takeoff weight of 7 metric tons.

The drone boasts a maximum payload capacity of 3.5 tons, equivalent to the total weight of 50 70kg adults. It can carry over 1,700 cotton coats or 700 disaster-relief tents in a single trip, delivering supplies over long distances. It has a maximum range of more than 3,000 kilometres, which is roughly equivalent to a nonstop direct flight from Beijing to Urumqi, the capital of the Xinjiang Uygur autonomous region.

It can take off and land on runways shorter than 500 meters and can use poor condition airports, such as those on plateaus and islands.

The aircraft is equipped with an 18-cubic-meter cargo bay that can be accessed from both the front and rear. According to its designers, the turnaround time can be as little as 15 minutes, greatly improving logistics turnover efficiency.

To ensure absolute operational safety, the Norinco Luca is fitted with two domestically-built turboprop engines and incorporates multiple safety redundancies for key systems, including the flight control, navigation and power supply systems. The aircraft also features smart health monitoring and fault self-diagnosis functions.

For those of you watching video streams from Artemis ll, close to the moon as I transmit this, high-resolution 4K footage is being live-streamed from the surface of the moon thanks to NASA’s laser-based O2O system. The cutting-edge Orion Artemis II Optical Communications system (O2O) will be used to beam 4K moon footage at up to 260 Mbps. We should also be treated to never-before-seen views of “the far side of the Moon, using Nikon digital cameras,” reports The BBC’s Sky at Night magazine.

The O2O system will also be used for fast and efficient transmission and receipt of procedures, pictures, flight plans, and more.

However, the astronauts are also using traditional radio communications to stay in contact with the ground team via NASA’s Deep Space Network (DSN). With prior mention of the potential for cloud interference to laser comms, this could be an essential backup. DSN was the key communications tech used by Voyager, the Mars rover, and Artemis I.

Losing sight of the Earth on a planned mission to the far side of the Moon will block both laser and DSN comms, notes the source report. NASA is well aware of this ‘dark window,’ which is estimated to last for 41 minutes.

And, if you aren’t that impressed by the 260 Mbps O2O laser comms terminal’s performance, NASA’s page about this laser technology highlights a Lunar Laser Communications Demonstration it has already completed that achieved 622 Mbps. Moreover, some nearer-Earth space laser comms projects have reached data speeds up to 200 Gbps.

This is Dave Reece ZS1DFR, keeping an eye on Nasa TV and YouTube channel, and reporting for HAMNET in South Africa.