Not Logged in

Hamnet




HAMNET News
Hamnet Projects and Events
Hamnet Emergency Frequencies
Emergency communication by amateur radio stations.
Hamnet Rules & Organization
Policy statement on membership of Hamnet
Hamnet Application Form
Minutes of last Hamnet meeting [PDF]
The HAMNET Manual
PDF format, right click and "save target as"
Hamnet Message Form
Minutes of last Teleconference


HAMNET SARL EMERGENCY COMMUNICATIONS DIVISION 


HAMNET AMATEUR RADIO EMERGENCY COMMUNICATIONS NETWORK 

IN HAMNET's Amateur Radio Report........a week of much activity - read more...........

Scroll down for more

 

 

 

 

WHEN ALL FAILS AMATEUR RADIO SUCCEEDS 

Something has gone terribly wrong. Normal ways of doing things are not working. The fastest way to turn an emergency into a full disaster is to lose communications.

Radio Amateurs understand emergencies. For over 70 years they have provided emergency communications for organisations. When normal ways of communication fail or get overloaded Radio Amateurs will be there.  

HAMNET, the National Emergency Communications division of the South African Radio League (SARL), provides communications for emergencies and can mobilise experienced communicators who with their own radio equipment will back up official channels or take over when all else fails.

 

The SARL represents all Radio Amateurs in South Africa at all levels of Government and through the IARU at the International Telecommunications Union. Radio Amateurs or "Hams" use two-way radio communication to make contact with other radio amateurs all over the world. They are even able to use satellites and on occasion speak with astronauts. Radio Hams can do this from home or while mobile in cars, boats or on foot.

Radio Hams have a full range of communication modes at their disposal. These include plain voice, Morse code, numerous digital computer modes and even graphical modes like television. A licensed radio amateur is able to join in experiments using all these modes.

.

 

-------------------------------------------------------------------------------------------------------------------

 

HAMNET CALL-SIGNS, MEETINGS AND BULLETIN SCHEDULES

Headquarters Report 

SUNDAYS - during the AMATEUR RADIO TODAY transmission, starting at 10h00 South African Standard Time (SAST), on HF and on many VHF and UHF repeaters around the country. (Current bulletin posted below)

Western Cape ZS1DZ or ZS1DCC

On the 1st Wednesday evening of the month, HAMNET's Western Cape monthly meeting is held at 19h30 SAST at Tygerberg Hospital's Provincial Emergency Management Centre.  

The radio bulletin is transmitted at 19h30 SAST on a Wednesday evening, on the local 145.750MHz repeater, with relays on to 1860 or 3760kHz LSB, 144.300MHz USB, and Echolink, via ZS1DCC-R, on the 2nd and consecutive Wednesdays of each month.

Eastern Cape ZS2PE or ZS2BRC

There is a weekly net on 52.950MHz at 20h00 SAST on a Wednesday evening, and local HAMNET news is included in the PEARS bulletin on Sunday morning at 08h45 SAST on the 145.700Mhz repeater, with a relay on to 7098kHz LSB.

Northern Cape ZS3NC

Free State ZS4DCC

KwaZulu Natal ZS5DCC or ZS84SIG

Quarterly meetings are held on the 2nd Saturday afternoon of the month, at 12h30 for 13h00 SAST, either at Ethekwini Disaster Managment Centre or the 84th Signals Unit in Durban. The next 2 dates are 10/9 and 10/12. 

On Sunday mornings at 07h00 SAST, on 145.625MHz, there is a bulletin, also relayed on to 3760 and 7110kHz, and you can listen on Echolink via ZS5PMB-R.

There is a formal radio bulletin at 19h30 SAST once a month on a Wednesday evening,on the 145.625MHz Highway repeater, and informal nets at the same time, and on the same frequency, every other Wednesday evening.

Gauteng South ZS6

Monthly meetings are held on the first Thursday of the month at 19h00 SAST at the East Rand Branch clubhouse. On all other Thursday evenings, a social gathering is held at the same venue to chat or maintain equipment. 

Gauteng North ZS6PTA

Limpopo ZS6

Mpumalanga ZS6

Northern Western Province ZS6 

  

 

------------------------------------------------------------------------------------------------------------ 

HAMNET REPORT 17th NOVEMBER 2019  

The weather in the KwaZulu Natal Midlands has been a strong topic of conversation this week after a tornado ripped through the New Hanover areas of Thokozani and Mpolweni on Tuesday. Cooperative Governance and Traditional Affairs (Cogta) spokesperson, Lennox Mabaso, said several homes and public infrastructure were damaged, and scores of people were hurt.

Cogta MEC Sipho Hlomuka, said preliminary reports received by the department indicate that a number of people who sustained injuries in the incident are receiving medical attention from surrounding hospitals. 

"A number of homes have collapsed, countless trees have been uprooted and the electricity supply in the area has been interrupted. Our teams are working hard to provide support to the affected communities,” said Hlomuka.

He said there are fears of missing people and possible deaths, and urged residents to be vigilant as the risk of heavy rains and severe thunderstorms continue to pose a serious danger to the province.

And on Wednesday, another tornado tried to touch down in the midlands, while heavy rains saturated large parts of central and coastal KZN. Low-lying areas quickly filled up, and gardens and roads were underwater by Wednesday evening.

Further forecasts of very heavy rain for Thursday and Friday fortunately didn’t materialize, as clouds and humidity were driven off the coast by late Thursday, resulting in a cloudless Friday.

The synoptic charts are starting to show the usual Spring and Summer low pressure trough, laying diagonally across the country, from Northern Namibia and Botswana, down to Eastern and Southern KZN, with high pressure cells off the Western and Eastern coasts of our country keeping all cold fronts firmly South of the country.

It would appear that the rainy season in the South West of the country is over, while the unpredictable summer storms start to make their presence felt in North Eastern areas. We trust that there will be enough rainfall to provide the farmers with good harvests.

Alex Schwarz, VE7DXW, has theorized for some time now that his RF-Seismograph, initially aimed at indicating band openings, seemed also to act as a real seismograph of sorts, with effects of earthquakes affecting HF noise levels and actually briefly enhancing HF propagation. Schwarz has some support from Professor Kosuke Heki of Hokkaido University in Japan, who has been researching whether changes occur in the ionosphere as a result of an earthquake.

The work of both citizen scientist Schwarz and space geodesy expert Heki caught the attention of Hackaday, the online publication with a stated goal of promoting "the free and open exchange of ideas and information." A November 12 Hackaday article, "HF Propagation and Earthquakes", outlines the observations of both men. According to the article, Heki "knew that changes in the ionosphere can affect GPS and GNSS receivers on the ground, and with Japan's vast network of receivers to keep track of the smallest of movements of the Earth's crust, he was able to spot an anomalous build-up of electrons directly above the devastating 2011 Tohoku-Oki earthquake, that preceded the earthquake by 40 minutes."

Heki's theory is along these lines: Chemical bonds in the rock -- specifically peroxy bonds between two oxygen atoms -- are broken by microfractures, leaving one side of the peroxy bond with excess electrons and the other with a positive hole. "These holes tend to migrate from high stress to unstressed areas of the rock, which leads them to eventually reach the surface, leaving it with a net positive charge," the Hackaday piece says. "As stress in the rock below increases, the number of positive holes reaching the surface rapidly multiplies, drawing electrons from the atmosphere to balance the charge. The moving charges generate an enormous electromagnetic field that can reach all the way up to the ionosphere, creating just the kind of anomalies that Professor Heki observed."

 

This week, Schwarz reported that the US Geological Survey recorded nine "significant earthquakes" on November 11, eight of which also were recorded by his RF-Seismograph. According to Schwarz, several small quakes early in the morning "opened the 40-meter band slightly, but the precursor of the quake [in Neiafu, Tonga] created a disturbance starting 4 hours prior to the quake and a total radio blackout between 03h30 UTC and 05h50 UTC. The quakes in late morning did not have a great effect on the local propagation. The one from Vanuatu created 80-meter propagation for 10 minutes only. At 23h40 UTC, another quake from Indonesia opened the 30-meter band again," Schwarz said.

The Hackaday article concludes, "Clearly, the RF-Seismograph is not yet ready to claim to have a solid predictive ability for earthquakes. For that matter, Dr. Heki's space-based observations aren't ready to stake that claim either. But it certainly looks like ionospheric changes can be correlated to earthquakes, both in time and space..."

And lest you think the earth’s mantle is a settled place, may I report that 46 earthquakes around the globe, with a magnitude of more than 4.5 on the Richter scale, were reported in Friday’s global disaster news! Our planet is indeed restless.

The ARRL Letter notes that December 11 marks the 98th anniversary of the success of ARRL's Transatlantic Tests in 1921, organized to see if low-power amateur radio stations could be heard across the Atlantic using shortwave frequencies (i.e., above 200 meters). On that day, a message transmitted by a group of Radio Club of America members at 1BCG in Greenwich, Connecticut, was copied by Paul Godley, 2ZE, in Scotland.

While the first two-way contact would not take place until 1923, the 1921 transatlantic success marked the beginning of what would become routine communication between US radio amateurs and those in other parts of the world -- the birth of DX.

To commemorate this amateur radio milestone, Maxim Memorial Station W1AW will be on the air through the day on December 11 with volunteer operators. The goal is to encourage contacts between radio amateurs in the US and Europe while showcasing the significance of the transmissions that pioneered global communication and laid the groundwork for technology widely used today.

The event will run from 13h00 until 00h00 UTC. Some details are still being worked out, but operation will focus on 40 and 20 meters SSB.

 

This is Dave Reece ZS1DFR reporting for HAMNET in   South Africa.

 


Copyright © 1997-2019    South African Radio League
This page last modified: 6/7/2016