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April 18 — World Amateur Radio Day
· HF · admin

In only two more weeks we will celebrate the WARD, the World Amateur Radio Day. At April 18 in 1925 the International Amateur Radio Union was formed in Paris. Just two years later, at the International Radiotelegraph Conference, Amateur Radio gained on shortwave the allocations still recognized today — 160, 80, 40, 20, and 10 meters. Since its founding, the IARU has worked tirelessly to defend and expand the frequency allocations for Amateur Radio. Today, Amateur Radio is more popular than ever, with more than 3,000,000 licensed operators! 

World Amateur Radio Day is the day when IARU Member-Societies can show their capabilities to the public and enjoy global friendship with other Amateurs worldwide. For 2021 the IARU Administrative Council has chosen “Amateur Radio: Home but Never Alone” as the theme for World Amateur Radio Day, Sunday, 18 April 2021. Faced with a pandemic that is forcing the adoption of extreme physical isolation to reduce the spread of the virus, the worldwide amateur radio community has responded positively to overcome the resulting social isolation. In the days and weeks following the onset of the pandemic radio amateurs reached out spontaneously to one another via the airwaves at the local, national, and global levels. On-the-air activity was at an unprecedented level throughout 2020, with record-breaking numbers of entries in the major contests.

More information at https://​www​.iaru​.org/​o​n​-​t​h​e​-​a​i​r​/​w​o​r​l​d​-​a​m​a​t​e​u​r​-​r​a​d​i​o​-​d​ay/.

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CW World Heritage Working Group
· General Conference, HF · admin

The IARU Region 1 Virtual General Conference in October 2020 approved the formation of a CW World Heritage Working Group as per proposal NS20_C4_09. More than twenty member societies agreed to their continued support regarding this working group.

Meanwhile an initial virtual meeting took place and attendants agreed to use Groups​.io as a platform for further elaborating the subject. This group acts as gathering discussions and experiences on the “a CW World Heritage” topic. Coordinator of this group is Egbert Hertsen, ON4CAS.

It is the aim of this working group to continue the initiative within IARU Region 1 to get Morse code on different national lists of intangible cultural heritage.

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Q & A: How far you can turn the dial when transmitting in SSB voice mode?
· HF, Spectrum · admin

Time and again the question arises as to how far you can turn the tuning knob when transmitting in SSB voice mode. Up to the edge of the band range? Using the 60 m band as an example, we will discuss the question here.

According to WRC-15, the range from 5351.5 to 5366.5 kHz, also called the “5 MHz band”, is allocated to the amateur radio service on a secondary basis. So, for example, are radio amateurs allowed to transmit on 5366.0 kHz within the WRC-15 60 m band in USB? [1]

The so-called “dial frequency” indicates only the frequency of the carrier suppressed in SSB. However, the modulation range for USB extends up to 3.0 kHz higher. That means 5366.0 kHz + 3 kHz = up to 5369.0 kHz. This means that a large part of the signal is outside the range assigned to the amateur radio service (see diagram, right signal, in red)! And: parts of the modulation spectrum cover the section intended for “narrow band weak signal modes”, such as WSPR. And thus leads to interference.

Therefore, the band plan indicates in the “notes”, that in the case of the 60 m band in USB, the highest “dial frequency” to be set is 5363 kHz (diagram, left signal, in green). Here the whole range of the modulation spectrum is below 5366.0 kHz. And thus both within the band and outside the “weak signal narrow band mode” range.

The same applies to the 20 m band: The highest frequency to be set in USB would be 14,347.0 kHz — i.e. 3 kHz below the upper band limit.

[1] Note: Individual countries have allocated a larger frequency range to the amateur radio service due to Radio Regulations Article 4.

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5 MHz Band in South Africa
· HF, News · admin

South Africa’s SARL has asked the communications regulator ICASA to allow radio amateurs a 100 kHz wide allocation in the 5 MHz (60m) band with 400 watts output. In terms of the outcome of the WRC-15, ICASA published on 25 May 2018 in the National Radio Frequency Plan an allocation of 100 kHz of spectrum to South African Radio Amateurs. There are two separate footnotes in the plan, splitting access to the 60m band into three segments.

In footnote 5.133B there is an allocation of 5351.5 to 5366.5 kHz with a power limit of only 15 W EIRP. This is the most common allocation in countries where 60 metres is permitted. In footnote NP 0, ICASA has allocated a full 100 kHz: “The 5350 — 5450 kHz segment and the channel 5 290 kHz are allocated on a secondary basis to radio amateurs under Article 4.4 of the ITU regulations.” ICASA has however not yet updated Annexure I of the Frequency Spectrum Regulations which stipulates power limits and modulation types. However, in the SARL’s motivation to have 100 kHz of 5 MHz spectrum allocated, the SARL requested a power limit of 26 dBW (400 Watts PEP) for ZS and ZR licence holders and 20 dBW (100 watt PEP) for ZU licence holders. These power limits are common in South Africa for all bands that are allocated on a secondary basis. On bands where amateur radio has a primary allocation, the power limit for ZS and ZR licensees is 30 dBW. The current situation is that these power limits for secondary allocations apply on 5 MHz except for the segment 5351.5 to 5366.5 kHz where only 15 Watt EIRP is permitted.

Source: SARL/SARN

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Petrinja Earthquake
· Emergency Comms, HF · Greg, G0DUB

An earthquake today at 12:19 UTC has caused severe damage in Petrinja in Croatia. The town is about 50 kilometres from the capital Zagreb. The neighbouring country Slovenia has shut down the Krsko nuclear power plant as a precaution. The earthquake reached a magnitude of 6.4, the epicentre was 46 kilometres southeast of the capital Zagreb, the Seismological Centre for the European Mediterranean reported on Tuesday. Initial reports spoke of major damage. The town of Petrinja, which has about 25,000 inhabitants, was affected. Roofs, facades and entire buildings collapsed, it said.

All services engaged in the earthquake-affected area are reported to be organised and have their own communications.

This earthquake is one of many in recent days and the national society HRS is asking members to be close to their radios and a net is formed on 3.675MHz as well as DMR and repeaters in case any assistance is needed. 

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