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VHF+ UHF+ MICROWAVE NEWS - FOCUS ON VHF with ZS6YZ 25 September 2022 

VHF, UHF and Microwave Record Table the latest table of records is available from the VHF SA Record page. Click here to get a copy. Compiled and updated by Paul, ZS6NK - Send your record claim to zssixnk@gmail.com


 

Focus on VHF and Above 2 October 2022

 Audio version

This past week there has been some great 6m openings to Europe, mostly FT8, but Pine ZS6OB also reported working 36 SSB and 1 CW station, which means that the opening was very strong. 

Kobus ZS3JPY posted an image one of the WhatsApp groups of the 6m activity between Southern Africa and Europe on Friday 30 September. It was busy. 

 

Well done to all the guys that made contacts. 

On the Wednesday evening meeting on Google Meet there were again some interesting discussions, mostly amateur radio related, but no long distant or strange reception reports have been reported. What I found interesting was that there was good tropo conditions forecast along the West coast on Wednesday and when I enquired, Kobus ZS3JPY, informed me that the weather had suddenly turned cold and with that there was no prospects for any tropoducting. 

Later in the week there was a decode received of a signal and almost immediately it was rubbished as a false decode. This forum is the place to discuss those interesting signals and decodes that you come across and try to understand how and why it was decoded. Come and join the interesting discussions. 

The next meeting will be this coming Wednesday at 20:00 on Google Meet 

VHF/UHF Long Distance Coordination Meeting

Google Meet link: https://meet.google.com/wzd-pqoa-uav 

Anyone is welcome to join in. 

Looking ahead at the Hepburn Charts there may be some good tropo conditions along the West and South Coasts on the country this afternoon around 1200 UTC. 

Hepburn_Chart_South Africa_1200UTC2Oct2022.png

 

There are also good conditions forecast across the South Atlantic on Tuesday 4 October with the possibility of making that elusive contact between the West Coast of South Africa and the East Coast of Brazil.

 

Hepburn_Chart_South Atlantic_0000UTC4Oct2022.png

 

WRC-23 agenda item 9.1b which is about the studies around the coexistence of the Amateur Services and Amateur Satellite Services and the RNSS Services on the 23 cm band is on going. Here is the latest report from Barry Lewis G4SJH, the IARU lead on this agenda item. 

“During the period 7 – 13 September 2022, the IARU once again participated in the preparatory work for WRC-23 agenda item 9.1b in ITU-R Working Party 4C (WP4C). The IARU summary report on the WP4C meeting can be found on the IARU R1 website. 

Updated studies were provided by France and new studies were contributed by the Russian Federation (GLONASS), China (COMPASS) and Japan. 

The IARU provided a contribution providing information agreed in WP5A highlighting the low duration of “busy times” for amateur activities in the 23 cm band. This information was adopted into the draft report. Whilst the studies confirm the potential for interference to occur into co-frequency RNSS receivers in almost the entire band, all the studies have assumed only static scenarios without any consideration of the geographic distribution and density of amateur transmitters or the temporal aspects of amateur or RNSS operations. Some studies take account of antenna patterns, but many results and conclusions focus only on worst case main beam consideration. The IARU Region 1 has published a commentary document on these aspects on the IARU Region 1 website. 

As a result of these studies and the regulatory status of the amateur service allocation, our ability to operate in certain parts of the band and at the power levels allowed today is likely to be constrained if regulators want to protect the RNSS receivers. This discussion will continue in the development of the Guidance Recommendation in ITU-R WP5A. 

WP4C plenary agreed to elevate the document to Draft New Report status and passed it to Study Group 4 (SG4) for adoption. Therefore drafting work is complete. 

Study Group 4 met on September 23rd and adopted the report for publication. IARU is totally engaged in the discussion that will continue in WP5A to ensure that the amateur services can continue to develop in this band and allow all the amateur applications in use today to continue.” 

More information and the submissions mentioned here can be found on the IARU Region 1 website at https://www.iaru-r1.org/ 

On Friday evening I responded to an urgent query from the IARU VHF Committee Chair Dick Harms PA2DW concerning the exact 23 cm spectrum that is allocated in the different countries within IARU Region 1. 

In last week’s SARL news there was a request to provide input on the proposed Next Generation Radio Frequency Spectrum Policy. There was a meeting on Thursday evening to discuss the comments so far and it is absolutely sad to see that there is no interest from the amateur community. 

The only inputs were from the folk who are already up to their eyeballs in the muck and putting in many hours promoting the hobby, and fighting for the recognition that our hobby so desperately needs, and to protect the frequency allocations that we are privileged to currently use. I use the word privilege, because frequency spectrum is a scarce asset and is commercially very valuable and we have no right to use any of it. We are privileged that we have the allocations available to us and we need to protect them as much as we can. They can be taken away with the stroke of a pen.

Should we loose a frequency allocation then there will be many moaners on their social media soap boxes saying that the SARL should have done more, but when we ask for assistance then no one is forth coming. Remember we, you and I, are the South African Radio League. It is not some organisation up there that has paid staff to do all the work. 

In the interest of the future of our hobby it is important that we, the greater amateur community, start taking serious notice of the threats to our bands and that we assist when requested to ensure that we can enjoy our hobby into the future. 

That is all the VHF and above news that we have for this week. 

What interesting project have you been working on or what exciting contact have you made on the VHF and above bands? 

Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za

 Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.

Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ.


Focus on VHF and Above 25 September 2022 

Audio version

 


I want to start this morning by giving an update on the 23 cm issue that is on the agenda for WRC-23.

 As the WRC-23 approaches studies regarding AI9.1b (23cm and RNSS) are working towards conclusions. However the IARU is not content that all the operational aspects of the amateur service usage of the 1240-1300 MHz band are being properlyconsidered. 

Having been deeply involved in the regulatory work described below it is the opinion of the IARU that for many national authorities the 23cm band WRC23 agenda item 9.1b topic has a very low priority. Many are taking a “generic” stance stating their support for studies without considering the detail of the work or how it is moving forward. This is exactly how I experienced the issue being dealt with at the ATU APM23-3 meeting that I monitored. Therefore the IARU requests that Member Societies urgently put this issue on the agenda with their national authorities to discuss the views laid out below. 

The IARU view is that the potential for widespread or persistent interference to the radio-navigation satellite service (RNSS) from amateur service transmitters is over-stated. However, recognising the regulatory situation, the IARU and the amateur community are ready to accommodate any technical or operational measures deemed necessary on the amateur services so long as they are proportionate, reasonable and evidence based. 

The IARU believes that a careful compromise needs to be found in the outcome of the work and the execution of WRC-23 agenda item 9.1b, that properly takes account of the low likelihood of interference events occurring whilst allowing both the amateur services and the RNSS to develop in the band.

The IARU stresses the opportunity that the higher frequency amateur service bands enable for technical skills development for researching and experiencing radio propagation effects. The 1240 - 1300 MHz band is important for the amateur radio service, being the lowest allocation for radio amateurs on which typical microwave propagation can be experienced. Access to these frequencies is facilitated by commercially available equipment and provides a ‘bridge’ building motivation to become involved in more specialized higher frequency microwave and millimetre wave operations providing the self-training which is at the heart of amateur radio. 

I think one of the most remarkable contacts this week was the contact on Tuesday 13 September when Tom ZS1TA managed to work both LU3EQ and LU4DPO via the RS-44 satellite. What is remarkable is that the satellite was no more that 5 degrees above the horizon on both sides of the Atlantic Ocean. Tom did it again from one of his favourite spots along Chapman’s Peak drive on the western seaboard of the Cape Peninsula. Well done Tom. 

On the Wednesday evening meeting on Google Meet there were again some interesting discussions, mostly amateur radio related, but no long distant or strange reception reports have been reported. 

This forum is the place to discuss those interesting signals and decodes that you come across and make them known to a wider audience. Come and join the interesting discussions.

 The next meeting will be this coming Wednesday at 20:00 on Google Meet

 VHF/UHF Long Distance Coordination Meeting

Google Meet link: https://meet.google.com/wzd-pqoa-uav 

Anyone is welcome to join in.

 Last week I mentioned that I have lodged a complaint with ICASA regarding interference on the 70cm band where there is a signal around 433.880 MHz that blots out all remote controls working on the license free portion of the band. I am please to say that ICASA has responded with a form that I needed to complete and they are scheduled to do an on-site visit towards the end of the month. They are very busy clearing a backlog of complaints that were lodged the previous month. 

This week there has again been tropoducting along the West Coast with reports of both the Cape Town beacon and the Rosh Pinah beacon being received. 

Looking at the WhatsApp groups it seems like loadshedding had quite an influence on whether or not contacts could be made during some good propagation conditions on 6m as well on Friday. Likewise on Saturday morning there was a lot of coordination taking place on WhatsApp during the VHF / UHF digital contest taking place this weekend. 

Going forward we definitely need to make plans to keep the radios on the air during loadshedding and for an extended time as well. 

Here in Pretoria, even the City of Tshwane Emergency Services Department has realised that they need to make alternate plans and are in discussions with HAMNET regarding the use of amateur radio when all else fails. As you have heard in the HAMNET bulletin, the Western Cape HAMNET members are already involved in exercises. 

Get those digital modes under the belt. Not FT4 or FT8. JS8Call, Winlink and possibly the new VarAC as well and not only on HF, we need to look at VHF as well when it comes to digital modes. We never know when our button will be pushed and we will need to deploy amateurs into the field to provide emergency communications. 

That is all the VHF and above news that we have for this week.

 What interesting project have you been working on or what exciting contact have you made on the VHF and above bands? 

Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za 

Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.

Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ.


Focus on VHF and Above 18 September 2022

 Audio version

I want to start this morning by giving an update on the 23 cm issue that is on the agenda for WRC-23. 

As the WRC-23 approaches studies regarding AI9.1b (23cm and RNSS) are working towards conclusions. However the IARU is not content that all the operational aspects of the amateur service usage of the 1240-1300 MHz band are being properly considered.

 Having been deeply involved in the regulatory work described below it is the opinion of the IARU that for many national authorities the 23cm band WRC23 agenda item 9.1b topic has a very low priority. Many are taking a “generic” stance stating their support for studies without considering the detail of the work or how it is moving forward. This is exactly how I experienced the issue being dealt with at the ATU APM23-3 meeting that I monitored. Therefore the IARU requests that Member Societies urgently put this issue on the agenda with their national authorities to discuss the views laid out below. 

The IARU view is that the potential for widespread or persistent interference to the radio-navigation satellite service (RNSS) from amateur service transmitters is over-stated. However, recognising the regulatory situation, the IARU and the amateur community are ready to accommodate any technical or operational measures deemed necessary on the amateur services so long as they are proportionate, reasonable and evidence based. 

The IARU believes that a careful compromise needs to be found in the outcome of the work and the execution of WRC-23 agenda item 9.1b, that properly takes account of the low likelihood of interference events occurring whilst allowing both the amateur services and the RNSS to develop in the band. 

The IARU stresses the opportunity that the higher frequency amateur service bands enable for technical skills development for researching and experiencing radio propagation effects. The 1240 - 1300 MHz band is important for the amateur radio service, being the lowest allocation for radio amateurs on which typical microwave propagation can be experienced. Access to these frequencies is facilitated by commercially available equipment and provides a ‘bridge’ building motivation to become involved in more specialized higher frequency microwave and millimetre wave operations providing the self-training which is at the heart of amateur radio. 

I think one of the most remarkable contacts this week was the contact on Tuesday 13 September when Tom ZS1TA managed to work both LU3EQ and LU4DPO via the RS-44 satellite. What is remarkable is that the satellite was no more that 5 degrees above the horizon on both sides of the Atlantic Ocean. Tom did it again from one of his favourite spots along Chapman’s Peak drive on the western seaboard of the Cape Peninsula.

Well done Tom 

On the Wednesday evening meeting on Google Meet there were again some interesting discussions, mostly amateur radio related, but no long distant or strange reception reports have been reported. 

This forum is the place to discuss those interesting signals and decodes that you come across and make them known to a wider audience. Come and join the interesting discussions. 

The next meeting will be this coming Wednesday at 20:00 on Google Meet 

VHF/UHF Long Distance Coordination Meeting

Google Meet link: https://meet.google.com/wzd-pqoa-uav 

Anyone is welcome to join in. 

Last week I mentioned that I have lodged a complaint with ICASA regarding interference on the 70cm band where there is a signal around 433.880 MHz that blots out all remote controls working on the license free portion of the band. I am please to say that ICASA has responded with a form that I needed to complete and they are scheduled to do an on-site visit towards the end of the month. They are very busy clearing a backlog of complaints that were lodged the previous month. 

This week there has again been tropoducting along the West Coast with reports of both the Cape Town beacon and the Rosh Pinah beacon being received. 

Looking at the WhatsApp groups it seems like loadshedding had quite an influence on whether or not contacts could be made during some good propagation conditions on 6m as well on Friday. Likewise on Saturday morning there was a lot of coordination taking place on WhatsApp during the VHF / UHF digital contest taking place this weekend.

 Going forward we definitely need to make plans to keep the radios on the air during loadshedding and for an extended time as well. 

Here in Pretoria, even the City of Tshwane Emergency Services Department has realised that they need to make alternate plans and are in discussions with HAMNET regarding the use of amateur radio when all else fails. As you have heard in the HAMNET bulletin, the Western Cape HAMNET members are already involved in exercises. 

Get those digital modes under the belt. Not FT4 or FT8. JS8Call, Winlink and possibly the new VarAC as well and not only on HF, we need to look at VHF as well when it comes to digital modes. We never know when our button will be pushed and we will need to deploy amateurs into the field to provide emergency communications. 

That is all the VHF and above news that we have for this week. 

What interesting project have you been working on or what exciting contact have you made on the VHF and above bands?

 Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za 

Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.

Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ.


Focus on VHF and Above 11 September 2022

 Audio Version

Well I think the highlight for me this week was the fantastic AMSAT SA Space Symposium that was held on Saturday. 

I have mentioned so many times that one needs to attend these symposiums as there is always an opportunity to learn something new. Some of you may say, but it is a Satellite Symposium. What does it have to do with VHF and Above? 

Well my answer to that is everything! 

The guys playing in the Satellite space use VHF and above frequencies for their uplink and downlink frequencies. I have previously spoken about that fact that we need to get more activity going on the microwave bands. 

The satellite guys are the guys playing in the microwave bands beyond 23 cm. QO-100 uses 2.4 GHz for the uplink and 10 GHz for the downlink. 

Not only did Hannes ZS6BZP again provide an excellent presentation on how you can build your own low cost QO-100 station, but Anton ZR6AIC spoke about how to build a 70 cm to 10 GHz transponder with off the shelf components.

Yes, that is still satellites, but working at those frequencies and building your own QO-100 ground station gives you the requisite knowledge and skills to understand that whether you send a signal up to the bird or via a terrestrial path is no different. The same equipment can be used, the only difference is where you point your antennas. 

This is exactly the kind of ingenuity that is required to get up into the microwave bands and it is affordable, and opens a whole new world above 23 cm. You do not build YAGI antennas at these frequencies. Well you can, but if you have built a 23 cm YAGI then you will know how critical the measurements are, so you now move over to a dish along with helix antennas and or feed horns if you go up to 10 GHz. Here in the Gauteng area we have plenty of high spots where we can set up kit and try and see how far we can work on the microwave frequencies. 

Great presentations Hannes ZS6BZP, Anton ZR6AIC, Tom ZR6TG, Hennie ZS6ALN and the two guest speakers from the US, Burns Fisher WB1FJ and Adam Farson VA7OJ/AB4OJ. 

For the sake of repeating myself. Do not miss out on these Symposiums. There is a wealth of information that is shared that is relevant to Amateur Radio whether you are a Satellite or a VHF and above enthusiast. We all use the same frequencies and we need to get active on them by any means. 

This week at the Wednesday evening Google Meet meeting Kobus ZS3JPY, Andre V51LZ, Danie ZR6AGB, Cor ZS6CR and myself who were online and again had some very interesting conversions. 

This forum is the place to discuss those interesting signals and decodes that you come across and make them known to a wider audience. Come and join the interesting discussions.

The next meeting will be this coming Wednesday at 20:00 on Google Meet 

VHF/UHF Long Distance Coordination Meeting

Google Meet link: https://meet.google.com/wzd-pqoa-uav 

Anyone is welcome to join in. 

This week there has again been tropoducting along the West Coast with reports of both the Cape Town beacon and the Rosh Pinah beacon being received. 

That is all the VHF and above news that we have for this week. 

What interesting project have you been working on or what exciting contact have you made on the VHF and above bands? 

Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za

 Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.


Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ.


Focus on VHF and Above 4 September 2022

 Audio version

This past week there has again been some tropoducting along the West Coast, with Chris ZS1FC reporting that he had heard the V51VHF beacon located at Rosh Pinah on Thursday. There have also been other reports of the beacon further up the coast, by Attie ZS3AD and Kobus ZS3JPY.

 

Looking ahead to the later part of next week more tropoducting is predicted along the West Coast of South Africa and Namibia.

Hepburn_Chart_South_Africa_1800UTC7Sep022.png

 

There are also some very intense conditions being predicted further off the coast that may have the effect of attenuating radio signals rather than enhancing them. It will be interesting to see the AIS plots for next week.

 

Hepburn_Chart_South_Atlantic_1800UTC7Sep022.png 

I have spent most of the past week monitoring the 3rd African Preparatory Meeting (APM23-3 )  of the African Telecommunications Union (ATU). There is not yet an African common position regarding Agenda Item 9.1.b as the studies are still ongoing and everyone is waiting to see what the recommendations will be for the ongoing sharing of the 23 cm band between the Radio Navigation Satellite Service who are the primary users of the band and the Amateur and Amateur Satellite Service who are the secondary users.

On Wednesday evening I also had a quick Zoom meeting with Barry Lewis G4SJH, the Chair of IARU Region 1 Spectrum and Regulatory Liaison Committee (SLRC) and we were given a heads up to keep an eye on the Scientific community and especially those entities playing with space weather sensors. Space weather sensors use an extremely broad range of frequencies, the introduction of protection requirements could potentially impact virtually all existing radio services, which includes bands of frequencies that have been allocated to the Amateur Radio Service. 

Another comment that Barry made was that there are too few volunteers to assist with reading through all the documents presented at the regional WRC Preparatory Meetings. The APM23-3 meeting alone had over 120 documents that were presented.

Did you know that the IARU has a spectrum monitoring system?

The role of the IARU Monitoring System (IARUMS) is to monitor the amateur bands to search and identify transmissions sent by intruders which is important because the amount of all kinds of intruders is rapidly growing! 

A number of national Monitoring Coordinators and volunteers have been watching our bands for many years. But more needs to be done to raise awareness of societies and countries where there are no national monitoring teams. Also, existing groups can still help by sharing detailed information worldwide with others. Monitoring is Teamwork! 

While the team includes amateurs in all three regions, Region 1 has been leading the team in recent years. They have also had some successes with interferers. More information can be found at https://www.iaru-r1.org/about-us/committees-and-working-groups/iarums/ 

The South African IARUMS coordinator is James Archibald ZS6NS. 

It is important that we amateurs monitor our bands and if we find intruders or strange activity on our bands that we gather as much information as possible including recordings and screen captures. We must not just ignore interference. Local interferers should be reported to the Regional office of ICASA closest to you. 

A complete list of ICASA Regional Managers can be found on the SARL website http://www.sarl.org.za/public/licences/licences.asp

 We request that you also copy artoday@sarl.org.za to allow the SARL to monitor how wide spread the problem is.  

This week at the Wednesday evening Google Meet meeting it was only Kobus ZS3JPY and myself who were online and believe it or not, spoke for nearly an hour on various topics. 

This forum is the place to discuss those interesting signals and decodes that you come across and make them known to a wider audience. Come and join the interesting discussions.

The next meeting will be this coming Wednesday at 20:00 on Google Meet 

VHF/UHF Long Distance Coordination Meeting

Google Meet link: https://meet.google.com/wzd-pqoa-uav 

Anyone is welcome to join in. 

That is all the VHF and above news that we have for this week.

 What interesting project have you been working on or what exciting contact have you made on the VHF and above bands? 

Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za

 Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.

Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ.


Focus on VHF and Above 28 August 2022

 Audio Version

This week at the Wednesday evening Google Meet meeting, Andre V51LZ, Kobus ZS3JPY and myself were online and we again had some interesting discussions around the tropoducting along the West Coast from 22 to 24 August. On Monday evening 22 August with the West Coast net there were some good contacts on 145.500 MHz FM, although the conditions were changing quite a lot. And then as Kobus puts it the fun started, Garry ZD7GWM let Kobus know that he was hearing the West Coast, but unfortunately they could not hear him.

Here is a recording made by Kobus ZS3JPY of Garry on 145.500 MHz FM. You will hear that the signal is reasonably distorted as well.

ZD7GWM_ZS3JPY_20220822.mp3

On the digital modes signals were enormous between Andre V51LZ in Oranjemund and Kobus ZS3JPY in Kleinsee. +14 to +19 dB on FT8 as reported by Andre. Andre also managed a FT8 contact with Sybrand ZS1SJ in Gordon’s Bay. Well done guys. 

V51LZ_FT8.jpg 

Kobus told me that on a previous occasion the FT8 signals were as much as 30 dB between himself and Andre. That is incredible. 

On both Sunday 21 and Monday 22 August Garry ZD7GWM on St Helena also received the FT8 signals from Kobus ZS3JPY and Andre V51LZ, but again no one received Garry. 

ZD7GWM_FT8_20220821.jpeg

 

The AIS station north of Andre in Oranjemund also showed some exceptional reports of shipping covering an area of over 38000 km2. 

AIS_Station_Kerbehuk.jpeg 

What was interesting is the variability of the tropoducting conditions and looking at the AIS data there seems to be a large variance in the ships being received between the various stations monitoring AIS data. What is also interesting is that certain stations appear to have better performance in certain directions which is strange as they all use vertical omnidirectional antennas. The location of the station and the height above sea level also plays a major role.

Thank you Andre and Kobus for the information that you sent me. 

This forum is the place to discuss those interesting signals and decodes that you come across and make them known to a wider audience. Come and join the interesting discussions. 

The next meeting will be this coming Wednesday at 20:00 on Google Meet 

VHF/UHF Long Distance Coordination Meeting

Google Meet link: https://meet.google.com/wzd-pqoa-uav 

Anyone is welcome to join in. 

This coming week the 3rd African Preparatory Meeting (APM23-3 ) leading up to the World Radio Conference in 2023 of the African Telecommunications Union (ATU) will take place from 29 August to 2 September. As you all know there are some very important items on the agenda for WRC-23 that affect our hobby, especially in the VHF and above bands. The APM23-3 meeting is a hybrid meeting taking place in Lusaka, Zambia, and Brian ZS6YZ will be attending the meeting virtually to monitor the proceedings and provide feedback to the IARU concerning any possible positions that the African Member States may take regarding the items of importance to Amateur Radio. The IARU only has monitor status at these meetings and all issues and representations needs to be made through the Telecommunications bodies, regulators and forums of the individual member states. While we have good representation in South Africa, the representation in the rest of Africa is poor. 

That is all the VHF and above news that we have for this week.

What interesting project have you been working on or what exciting contact have you made on the VHF and above bands?

 Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za 

Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.

Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ


Focus on VHF and Above 21 August 2022

 Audio Version

I have previously spoken about the ICOM SHF Project – Super High Frequency Band Challenge. The prototype was showcased at the Dayton Hamvention in Ohio, USA in May 2022. This project has now been given a product number and it has an option to go to 10 GHz as well.

ICOM announced the new IC-905 VHF/UHF/Microwave transceiver at the Tokyo Ham Fair which is taking place this weekend 20-21 August.

 

ICOM_IC905.jpg 

This multi-mode transceiver covers the 144, 430, 1240, 2400 and 5600 MHz bands and has an optional module CX-10G for the 10 GHz band.

In addition it provides support for ATV operation as well.

The ICOM promotional video was released at 01:10 UTC on Saturday, 20 August.Watch (English Subtitles) Icom New Product Introduction Video on Youtube 

https://youtu.be/kzGQWmTKNzc

More information can be found on the Icom UK website
https://icomuk.co.uk/Icom-IC-905-VHF-UHF-SHF-Transceiver-Announced-at-Tokyo-Hamfair-2022/2/3250/ 
and pre-release information can be found at https://icomuk.co.uk/files/icom/PDF/newsFile/IC-905_leaflet_at_Ham_Fair_2022.pdf 

Or just search for “youtube icom ic-905” in your favourite web browser to get more information. 

This certainly looks like it will be a very nice multi-mode radio for amateurs  to get active on the VHF and above bands. 

This week Kobus ZS3JPY, Andre V51LZ, Cor ZS6CR, Danie ZR6AGB and myself were on Google Meet on Wednesday and there were again  interesting discussions around unexpected signals being received and decoded. An example this week was the reception of LoRa433 signals received from the Fossasat satellites. In this case the signal was received by four amateur stations from a satellite that was around 8 100 km away and below the horizon for South Africa. How is it possible? 

Fossasat_decodes.jpeg 

Other discussions were about so called false decodes in the digital modes and whether or not they are actually false decodes or actually genuine signals received due to some unexpected propagation phenomenon. Cor also discussed that there were settings that one could do to minimise the possibility of false decodes. He had found a lot of discussions regarding this in the EME forums. 

Time was also spent discussing on interesting AIS decode that was being received over 4000 km away in Sicily from an AIS beacon in the Gulf of Guinea at 0° S and 0°E. Andre V51LZ was going to see if he could find more information about this beacon. 

AIS_Decode.jpeg 

The AIS system is an automatic tracking system that uses transceivers on ships broadcasting in the 160 MHz marine band and is intended, primarily, for maritime safety to allow ships to view marine traffic in their area and to be seen by that traffic. There are systems that make use of VHF and Satellite to pass their information back to receiving stations. What is interesting is that firstly the antennas on the ships and base stations on land are all vertically polarised and secondly AIS data is also plotted on the dxmaps.com website by amateurs to give indications of tropoducting opportunities. Every ship in the sea that has a VHF AIS system is a potential beacon that can be used to get an indication of tropo conditions along the coast. 


This is also the intention of the SARL Beacon project where we are trying to get beacons up and running at various locations around the country that are automatically monitored and that can be used to better understand VHF propagation inland as well. We actually have too few members working on the project and an enormous task is on the shoulders of a few amateurs.

The consensus amongst the Wednesday evening group is that these strange occurrences and decodes should not just be discounted and needs to be studied to try and understand the WHY and HOW it is possible that these signals are received. It makes one realise that there is a lot more happening in the upper atmosphere than we think and that we actually know very little about propagation in the VHF and above bands. 

This forum is the place to discuss those interesting signals and decodes that you come across and make them known to a wider audience. Come and join the interesting discussions. 

The next meeting will be this coming Wednesday at 20:00 on Google Meet

 

VHF/UHF Long Distance Coordination

Wednesday, 13 July · 20:00 – 21:00

Google Meet joining info

Video call link: https://meet.google.com/wzd-pqoa-uav

 

Anyone is welcome to join in. 

This past week, Johan V51JH has again been pointing his antenna towards Cape Town transmitting a FT8 signal. I am not aware on any reception reports. 

Kobus ZS3JPY also gave me the heads up that there may be good tropoducting along the coast this coming week with conditions peaking on Tuesday afternoon.

 

Hepburn_Chart 1800UTC23August2022.jpeg 

That is all the VHF and above news that we have for this week.

What interesting project have you been working on or what exciting contact have you made on the VHF and above bands? 

Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za 

Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.

Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ.


Focus on VHF and Above 14 August 2022

 Audio Version

Last week I mentioned the contact that Janre ZS6SI made from Kranskop in Limpopo. Janre has also made a 44 km CW contact with Michael ZS6MSW on 2m. This time he was here in Pretoria. As Janre says on a WhatsApp post “ 2m CW and SSB is blowing my mind. This was 44 km over the mountains on 5 W”.  Well done Janre. 

Yes, one must not under estimate the distances that can be achieved with VHF and UHF especially if one uses modes, other than just FM. 

Venturing higher into the microwave bands a very nice contact has been made in Europe on 10 GHz between the Canary Islands and Portugal. 

Miguel CT1BYM says on the website of the Portuguese Broadcasters Network REP “In the evening of 30 of July, the QSO was done between EB8BRZ at grid IL28ha and CT1BYM at grid IM57pc. This was my first ever QSO done at 10 GHz between EA8 and CT, using tropospheric propagation with a distance around 1187 km. It was also a first for Cecilio, EB8BRZ.

A beacon was installed on my balcony, direction EA8, with 2W and a 10dBi horn, transmitting CW and Opera. The beacon runs 24×7, helping identifying the possible QSO window. Beacon runs at 10368.825MHz and is  TCXO disciplined.

 

10GHz_Beacon.png

 

The beacon signal was received at EB8BRZ at 19:34 UTC, so we decided to go to SSB immediately.

At Cecilio EB8BRZ, the working conditions were a 60 cm Procom prime focus dish, 2W, and an IC-705 for IF.

 

144MHz_IF.png

 

60cm_Procom_prime_focus_dish.png

 

At CT1BYM QTH, the working conditions were a 60 cm offset Kathrein dish, 3W, GPSDO and an IC-910H with OCXO.

 

60cm_offset_Kathrein_dish.png

 

At 8:06 UTC signals peaked at 9+10dB, excellent conditions! We will test a lot more things next days, including monitoring the Opera mode from the beacon, tracking tropo conditions.”

I’m assuming the time should have been 20:06 UTC and not 8:06.
 

Thank you Miguel CT1BYM for this report. 

This week Kobus ZS3JPY, Attie ZS3AD, Andre V51LZ, Tom ZS1TA and myself were on the Wednesday VHF/UHF Long Distance Coordination meeting. We had some very interesting discussions around tropoducting and some of the interesting observations regarding the AIS signals received from the various AIS monitoring stations and how the height above sea level affected the direction and range of the signals detected by the different receivers. 

The next meeting will be this coming Wednesday at 20:00 on Google Meet.VHF/UHF Long Distance Coordination

Wednesday, 13 July · 20:00 – 21:00

Google Meet joining info

Video call link: https://meet.google.com/wzd-pqoa-uav

 Anyone is welcome to join in. 

This past week, Johan V51JH has been pointing his antenna towards Cape Town transmitting a FT8 signal. 

I found the following on Southgate Amateur Radio News about the new revamped ARRL Laboratory. 

ARRL has unveiled its new Radio Laboratory, W1HQ. In a new YouTube video, Jherica Goodgame, KI5HTA, a summer intern at ARRL Headquarters, tours viewers through the station.

"The ARRL Radio Lab is an innovative test space designed to reshape the way we imagine and build a ham radio shack," said Goodgame. The station is intended to inspire members to build, organize, and equip their own stations in innovative ways. "From a decluttered workspace and a digital user interface, to being able to remote into the equipment from anywhere, W1HQ is a step towards the future of amateur radio stations," Goodgame added.

The station includes a new tower and antennas atop the main administrative building at ARRL Headquarters in Newington, Connecticut. Inside the station, three operating positions provide an interface to rack-mounted and computer-controlled transceivers, amplifiers, antenna switches, and rotators.

Goodgame explained that the Radio Lab will also support equipment testing and QST Product Review. "An extension of product reviews in the future will be to take that piece of gear that we're testing, put it on this test bench, and see how it integrates with a station that's already under full automation and control," she said.

The video is published on ARRL's YouTube channel at https://youtu.be/68BJxGHg74Y.
 

Wow, what a state of the art radio room. My radio room has a long way to go. 

That is all the VHF and above news that we have for this week.

What interesting project have you been working on or what exciting contact have you made on the VHF and above bands? 

Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za

 

Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.

Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ.


Focus on VHF and Above 7 August 2022

 Audio Version

It is really nice to see the younger radio amateurs experiencing the hobby and especially the VHF and above bands. Janre ZS6SI a relatively new amateur has been playing on VHF and UHF for a short while with a modest set up of a Yaesu FT817 and an AMSAT SA dual band Yagi. On Saturday morning Janre climbed Kranskop near his home town of Modimolle or Nylstroom for the guys who are not familiar with Modimolle and made some nice 2m and 70cm contacts.

 

Kranskop.jpeg

Kranskop is in grid KG45gg. Here is a 70cm contact Janre made with Koos ZS6KSG at KG33wu, a distance of just over 170 km.

 

Janre ZS6SI Kranskop

 

 ZS6SI_ZS6KSG_70cm Contact.mp4

 

 Earlier in the week when Janre was testing his set up from Groenkloof in Pretoria where he lives while studying at the University of Pretoria and made his first SSB contacts with John ZS6JGL and Carl ZS6CBQ he made the comment “Die VHF gogga het sopas gebyt” Well done Janre, great to see the enthusiasm for VHF and above amongst the younger amateurs and it just shows what can be done with a QRP radio and a good antenna on the VHF and above bands.

This week only Kobus ZS3JPY and myself were on the Wednesday VHF/UHF Long Distance Coordination meeting. Loadshedding seemed to have made it difficult for some of the guys who are usually in the discussions. 

The next meeting will be this coming Wednesday at 20:00 on Google Meet 

VHF/UHF Long Distance Coordination

Wednesday, 13 July · 20:00 – 21:00

Google Meet joining info

Video call link: https://meet.google.com/wzd-pqoa-uav 

Anyone is welcome to join in. 

Johan V51JH still has his horizontal antenna pointed towards Krugersdorp and transmitting a FT8 signal. No signals have been heard lately in either Gauteng or Secunda, but that does not mean that it will not happen.

Carl ZS6CBQ posted an interesting Hepburn chart for Thursday morning 0600 UTC.

 

ZS6CBQ_Hepburn_Chart_.0600UTC220804.jpeg 

 

The chart shows a patch of tropoducting situated over an area north of Kuruman in the Northern Cape. These types of atmospheric anomalies needs to be investigated further and exploited where possible. 

Looking ahead Kobus ZS3JPY posted a Hepburn chart of the South Atlantic for Monday evening 1800 UTC showing some possibly good tropoducting between the West Coast of South Africa and Namibia and the East Coast of Brazil.

 

 

Hepburn_Chart_South_Atlantic_1800UTC_220808.jpeg

 

 

Kobus says this is the best forecast that has been seen since 2016.

Hepburn_Chart_South_Atlantic_2100UTC_161005.jpeg
 

Thanks for that heads up Kobus. I am sure that there will be many antennas pointing across the South Atlantic this coming week. 

That is all the VHF and above news that we have for this week.
Apologies for another short program. 

What interesting project have you been working on or what exciting contact have you made on the VHF and above bands? 

Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za 

Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.

Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ.


Focus on VHF and Above 31 July 2022

 Audio version

Johan V51JH is back from holiday and has his station transmitting throughout the day on 50W and in the evenings when he is at home he increases the power to 600W. There have been a number of amateurs listening out for the signals and exploring Aircraft Scatter to better understand how signals can be reflected off the passing aircraft.

While no reception reports have been received this past week, there continues to be some interesting discussions around long distance communications on the Wednesday meetings and it also dominated part of the VHF Work Group meeting on Thursday as well. 

The next meeting will be this coming Wednesday at 20:00 on Google Meet VHF/UHF Long Distance Coordination

Wednesday, 13 July · 20:00 – 21:00

Google Meet joining info

Video call link: https://meet.google.com/wzd-pqoa-uav 

Anyone is welcome to join in. 

Some feedback from VHF Work Group meeting held on Thursday which primarily focus on the SARL Beacon project. The MoU for the Karoo beacon site has been signed and will be returned to us shortly. The land owner has  asked that we continue in the mean time with the project. A target date for installation of the Karoo beacon has been set for the end of February 2023. Once Len ZS3LEN goes back to site then he will draw up a site plan that the working group will use for planning the improvements such as fencing and additional solar resources that needs to be installed. Cor ZS6CR has made good progress with the documentation for the telemetry and control of the beacon and has already got a basic system that he is testing. Work is progressing on looking at what antennas should be used for the Karoo Beacon.
The work group will also be placing some priority on getting the QRP-Labs U3S beacons on the air. All three beacons are fully operational and just require amplifiers to be built for them. The plan is to place one of the beacons on the Bethlehem test site as well.
 

Cor ZS6CR sent me some information that surfaced at a recent Club meeting in Secunda that a certain home-automation-ready PIR motion sensor operating on 433 MHz may be interfering across the 70cm band.

Club members will investigate the extent of this interference and provide feedback. 

There is a 433 MHz license free segment in the middle of the amateur 70 cm band, but we should not see interference from devices operating in this license free segment. With the growth of IoT or Internet of Things there are a lot of devices operating on 433 MHz like remote control power sockets, PIR, door sensors and much more so one can expect that some devices may generate spurious signals outside of the license free segment.

Are there any other amateurs who have or has experienced interference from devices operating in this 433 MHz license free band? Please let us know at vhfnews@sarl.org.za so that notes can be compared and more information can be gathered in order to report the problem to ICASA for further investigation. 


This past week a number of amateurs have been making contact with the ISS. The downlink frequency is 145.800 MHz and the uplink frequency is 145.200 MHz. You can get information about the passes using software like Gpredict that runs on most platforms. Gpredict can be downloaded from http://gpredict.oz9aec.net/  

Gpredict.jpeg 

Bernie ZS4TX will be conducting a 2M EME DXpedition to Angola from 12-16 August 2022. Bernie will be using the callsign D2TX. Bernie says on the D2TX page on QRZ.com that the expedition includes a 10 day ~6000km road trip crossing the Namibia, Botswana and Angola borders. As far as can be determined, this will be the first time that D2 is active on 2M EME or EME on any band. Bernie also mentions that he will also be on HF [CW] 40M and up, 100W only. Good luck Bernie, safe travels and hopefully there will be many EME contacts for D2TX. 

That is all the VHF and above news that we have for this week.
Apologies for a rather short program. There has been relatively little activity on the VHF and above bands that has come to my attention. 

What interesting project have you been working on or what exciting contact have you made on the VHF and above bands? 

Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za 

Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.

Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ.


Focus on VHF and Above 24 July 2022

 Audio version

The Wednesday evening VHF/UHF Long Distance Coordination meeting continues to bring up some very interesting discussions around the topic.

On Sunday last week Carl ZS6CBQ sent me a lengthy WhatsApp message about discussions that he and Dick ZS6BUN had about the decode that Cor ZS6CR picked up on 8 July at 14:08 UTC. They feel that it was Aircraft Scatter that resulted in the decode. This was discussed at length on the group discussion held on Wednesday evening as well, and it is definitely something to explore further.

Carl says “I went and looked on Flight Radar history and at that time Flight DAL200 from Atlanta was exactly in place over Botswana flying at 12 000 meters.   Last Friday 15 July I was watching on Flight Radar and was surprised to see that different flights cross over this spot more or less at the same time at different heights. There were 4 planes, 3 big Airbus 380's, the one from Atlanta DAL200, ETH846 to Addis Ababa, SAA 2968 and a smaller 737 to Windhoek.

 

Flight _Radar_15_July_2022.jpeg

 

Carl says that he and Cor ZS6CR were monitoring 144.174 MHz at that time but did not get any decodes but unfortunately Johan V51JH had switched off on his side.

 

Carl goes on to say “this spot is just south west of Gabarone where overseas flights from America to Johannesburg and Cape town to Europe crosses at the same time on Friday afternoons. I watched again on 15 July but it was not the same. It seems that more flights are coming in on Fridays. Then you also have the afternoon flights of SAA to Windhoek and Walvisbay.

This spot will only effect Div 6 stations in Gauteng and a section of east of Gauteng. There is not a another spot where aircraft paths cross like this. All the flights between Cape Town and Johannesburg are in straight lines North and South.

On Friday afternoon 22 July flight DAL200 was late and flying more north, but it's path was crossed by the Cape to Addis Ababa flight ETH846 and it was more north than normal as well. So the planes are most of the time exactly at the same spot every week, but it can change.”

 

While writing this weeks program on Saturday at around 10:00 UTC there were again three flights crossing at that same point. 

Flight_Radar_Screenshot_from _2022-07-23_11-56-53.png


Concerning the modes to use with Aircraft Scatter, Carl says “I found that FT4 is a faster and better mode to use on longer distances with Aircraft Scatter, and would suggest the following:

 

1. That we use FT4 mode.

2. Station from V51 TX 2nd and Stations from Div 6 TX 1st.

 

We can try more Aircraft Scatter between all the provinces during peak flight hours in the mornings, evenings and weekends, and I suggest Div's 1,2,3 and V51 TX 2nd with Div's 4,5,6  TX 1st all on FT4.”

 

Carl says that inland lots of QSO's can be made with Aircraft Scatter and that he uses it often between Krugersdorp and Bethlehem, Krugersdorp and Bloemfontein as well as Krugersdorp and the Northern Cape. Carl recommends that to be able to use Aircraft Scatter to our advantage we need to use FLIGHTRADAR24 which is an Android App and can be used via a web browser as well https://www.flightradar24.com/.

 

Thanks Carl for these interesting insights regarding aircraft scatter.

 

Let us talk a little about the history of Aircraft Scatter.

The first radio-based detection of aircraft was accomplished by L. A. Hyland of the U.S. Naval Research Laboratory in June 1930 using a 33 MHz CW signal. The detection was accidental, as Hyland was working on ground-based direction finding equipment at a military airport and astutely noted that the received direction-finding signal increased when aircraft passed through the direction-finding beam.

 

The history of amateur use of Aircraft Scatter goes back at least to 1967. In August 1967 Henry Root, W1QNG, wrote a two-page article for the Technical Correspondence section of QST discussing the theory of Aircraft Scatter, with the title “Using Aircraft Reflections in V.H.F. Communications”.

 

When an aircraft crosses the path of a radio signal, the aircraft will cause the signal to scatter in all directions. Backscatter is primarily what is used in radar systems that track aircraft in the sky. Here transmitter and receiver are normally co-located. The signal will also be reflected in the forward direction and be received by another station in a different location. This is known as bi-static radar. It stands to reason that the amount of signal reflected is very small and there are equations available that can be used to calculate the path losses and expected level of the received signal. There is also some magic that happens when the aircraft flies directly in the path between the two stations. This magic manifests itself as signal enhancement, sometimes as much as 20 to 30 dB or more. As a result of this, Aircraft Scatter propagation is sometimes referred to as Aircraft Enhancement.

 

There are a number of factors that affect the possible contact via Aircraft Scatter. The speed at which the aircraft is flying. Whether the aircraft flies in the path between the two stations or crosses the path. The size of the aircraft also affects the amount of signal that is scattered and of course the number of aircraft in the sky.

 

Aircraft Scatter is more popular in areas where the airspace is busy as in Europe or the US. Here is Southern Africa there are considerably less aircraft in the sky, although there are times when the airways are busy for instance in the early morning or late afternoon with aircraft landing and taking off from OR Tambo or Lanseria airports.

 

There is a wealth of information available as well as software that can assist you to explore this interesting VHF and above mode. Take a look at the website of Roger, W3SZ at  http://www.nitehawk.com/w3sz/AircraftScatter.htm.

 

You can also find AirScout software written by Frank, DL2ALF. You can also find a host of articles on aircraft enhancement on the website of David, VK3HZ at http://www.vk3hz.net/ae.htm.

 

Tom ZS1TA also gave feedback about discussions he has been having with the clever guys out there as he puts it, regarding the short bursts of FT8 tones that he has been receiving from the station of Johan V51JH. Tom says that the consensus is that it may well be Meteor Scatter that resulted in the bursts of FT8 tones that he received. There are continuously meteors entering the earth’s atmosphere and burning up, not only when the well known meteor shower events take place. Tom also says that he had good Meteor Scatter activity throughout the day as documented in the recent article in Radio ZS when he was in Paternoster.
This is true and I have spoken about the Snowtel network in the US that uses Meteor Scatter to transmit accumulated snow levels from monitoring stations in the mountainous regions back to a receiving station. It is something Nigel ZS6RN and myself have also discussed at length in the past.

 

The next meeting will be this coming Wednesday at 20:00 on Google Meet

 

VHF/UHF Long Distance Coordination

Wednesday, 13 July · 20:00 – 21:00

Google Meet joining info

Video call link: https://meet.google.com/wzd-pqoa-uav 

Anyone is welcome to join in. 

This is a fascinating hobby of ours and there is so much that we can discover and learn more about and these Wednesday evening discussions  are fantastic for exchanging ideas and experiences. Thank you for everyone who has joined and shared their ideas and experiences so far. There are a number of us who eagerly listen and learn and look forward to the next week’s discussion. 

What interesting project have you been working on or what exciting contact have you made on the VHF and above bands? 

Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za 

Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.

Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ.


 

Focus on VHF and Above 17 July 2022

 Audio version 

On Wednesday evening a small group of VHF enthusiasts met to discuss and share some ideas regarding 2m propagation experimentation. We had a fruitful discussion and went away with some ideas on a way forward for now. We also decided to review the different digital modes and see which would perhaps be better suited for VHF propagation testing. Johan V51JH will also be away on a much deserved break and will be back at his QTH in Swakopmund again in the last week of July and then he will again be running his station continuously for propagation testing. The group also decided to establish another WhatsApp group specific for 2 m propagation experimentation to allow for quick communications amongst the group.

 

The next meeting will be this coming Wednesday at 20:00 on Google Meet

 

VHF/UHF Long Distance Coordination

Wednesday, 13 July · 20:00 – 21:00

Google Meet joining info

Video call link: https://meet.google.com/wzd-pqoa-uav

 Anyone is welcome to join in.

Tom ZS1TA sent an email on Friday morning detailing his experience monitoring the signal that Johan Z51JH has been transmitting this past week with his antenna pointed towards Cape Town. 

Tom says “Was able to monitor Johan’s FT8 transmission for virtually 12 hours straight yesterday, Thursday. The load shedding schedule was once at 6am and again at 10pm, allowing most of the day uninterrupted. 

No decodes were recorded, however as during the day before I periodically received short pieces of the FT8 tone. Mostly about half a second and absolutely clear in the speaker. The tone was pure and without distortion. 

I do not believe these were MS reflections due to their clarity and no evidence of Doppler or frequency shift. They were always on Johan’s frequency and in the second period as he transmitted.There was no tropo-ducting evidence on Thursday and no AIS activity recorded so assume it was some sort of direct propagation.” 

Tom also sent some photos of the short bursts of FT8 tones that he received.

 

Tom mentioned that it takes some work for try and receive these tones especially competing with local QRM that he experiences at his QTH in Cape Town. 

This is what makes propagation experiments so interesting and yes, it is time consuming, but being able to coax the signal out of the noise is what makes it great. Again, it takes RF to be transmitted and listeners to know where and what is being transmitted to patiently look for that signal. 

I have found a very good RSGB presentation on VHF Propagation. This video is a good introduction for the new amateurs who want to start exploring the world above 30 MHz. 

https://www.youtube.com/watch?v=5Yo4IFn6AAY 

In fact the RSGB has a whole range of excellent videos on their YouTube channel if you use the search term VHF once you are on their YouTube channel. They are well worth watching. 

https ://www.youtube.com/user/TheRSGB/search?query=vhf 

What interesting project have you been working on or what exciting contact have you made on the VHF and above bands? 

Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za

 

Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.

Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ.


Focus on VHF and Above 10 July 2022

 Audio version

On Friday afternoon Cor ZS6CR posted a photo of a FT8 decode that his system received from the station of Johan V51JH in Swakopmund on the VHF UHF SHF Amateur Radio Whats App group.

 

 

 

 

 

 

Johan had left his radio calling CQ on 50 W when he left for work in the morning. Another interesting fact is that Johan’s 2m Yagi antenna is pointing to Cape Town as he has a problem with his rotator. Cor had his 2m Yagi pointing in the direction of Carl ZS6CBQ as they had made contact on Wednesday evening on 2m. Cor had also left his radio monitoring the frequency on FT8. Johan V51JH is in approximately the same direction and at a distance of 1545 km from Cor’s QTH.

 The big question?

The big question is why and how Cor was able to receive this signal. As Cor said to me on Saturday morning during a telephone call that his phone did not stop ringing the previous night with guys looking for more details to try and understand the why and how. One view which seems to be the most plausible is that it may have been Sporadic-E propagation. We know for sure that it is not tropo or tropoducting as the conditions are not right at the moment even though there was tropoducting along the West Coast on Friday evening and it most probably was not Meteor Scatter either. 

We will never really know the how or why here, but what is important is that we realise that if there is no one transmitting and no one receiving on a given frequency then the likely hood of a contact will not exist. This stresses again the importance of the SARL beacon project that is currently on the go.

It will still be a while before the beacon will go live in the Karoo, but in the mean time there are other ways to test long distance propagation, but it requires RF to be transmitted 24/7 on the one side and dedicated monitoring 24/7 on the other side. We have all the tools available to us, we just need to use them.

So how do we go about with a coordinated effort to achieve this? 

After discussions between Cor and myself on Saturday morning we decided to throw it out to the greater VHF/UHF group out there. We have dedicated VHF/UHF enthusiasts across the both South Africa and Namibia from Swakopmund, down the West Coast to Cape Town, along the South and East Coast as well as internally in divisions 4 and 6. The suggestion is to come together weekly on an evening and exchange ideas how this can be achieved. Our suggestion is that those interested in exploring these long distance communications possibilities get together on Google Meet on a Wednesday evening at 20:00 SAST. Who ever is interested and available is free to join the group discussion. 

The first meeting will be this coming Wednesday at 20:00 on Google Meet. 

VHF/UHF Long Distance Coordination

Wednesday, 13 July · 20:00 – 21:00

Google Meet joining info


Video call link: https://meet.google.com/wzd-pqoa-uav

 

We will meet every Wednesday at the same time on the same link and hopefully over time more folk will join the discussion which will lead to more coordinated RF in the air and more coordinated monitoring for these RF signals. See you on Wednesday at 20:00 on https://meet.google.com/wzd-pqoa-uav

I found another podcast by Onno VK6FLAB that caught my attention and also provides some very interesting information about the Amateur Radio Digital Communications Foundation. 

Listen to Onno VK6FLAB - If you had money, what would your amateur adventure look like?  

VK6FLAB_If_you_had_money.mp3

What interesting project have you been working on or what exciting contact have you made on the VHF and above bands? 

Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za

Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.

Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ.


Focus on VHF and Above 26 June 2022

Audio Version  

I have mentioned the issue between the RNSS and amateur radio on 23cm recently, but I want to provide some more feedback as this is important to us amateurs as the 23 cm band is one of the busiest bands where a lot of new activity is taking place on, especially in Europe. 

The C5 committee met on Thursday 23 June 2022 for a hybrid meeting. Approximately half of the delegates were present in Friedrichshafen while the other half of the group were present via Zoom.

Brian Jacobs ZS6YZ attended the meeting on behalf of the SARL. 

The meeting kicked off at 09:00 and the first topic on the agenda was Spectrum Matters with most of the morning dedicated to feedback and discussions on the WRC23 agenda item 9.1.b which is about the coexistence between the Radio Navigation Satellite Services (RNSS) who are primary users and the Amateur and Amateur Satellite Services who are secondary users on the band. 

Barry Lewis G4SJH, who is the IARU global lead on this agenda item gave a presentation and feedback regarding the work done and the studies undertaken so far. 

The greatest challenge is that both the RNSS services and the Amateur services are co-frequency across the whole band. 

 

Zooming into the band we see the following picture showing the IARU band plans superimposed on the RNSS systems.

Challenges that exist for the amateur services are the following:

·       Amateur operations are co-frequency almost everywhere in the band.

·       Amateur station operators do not know where or when an RNSS user is active.

·       An RNSS user will most likely be unaware that interference is occurring.

·       New “High Accuracy” services under development with commercial ambitions.

·       Widespread deployment of RNSS receivers.

·       As secondary users, amateurs may not cause interference to primary users.

·       There are two highly publicised incidences of interference. 

Two technical studies have been conducted.

One study made use of propagation model predictions to estimate the distance over which harmful interference could be caused to an RNSS receiver.

The other study made measurement programmes to assess the impact of various amateur radio application emissions on the RNSS receivers.

The results of these two studies are in the process of being documented and studied along with the two documented cases of interference that happened in Germany where an ATV signal was received by a GALILEO control centre and in Italy (Varese) where a FM repeater interfered with receivers in the European Commission Joint Research Centre in Ispra.

A couple of points to bear in mind.

1. The removal of the amateur allocation is out of the scope of resolution  for WRC23 as the resolutions clearly states

resolves to invite the ITU Radiocommunication Sector

1. to perform a detailed review of the different systems and applications used in the amateur service and amateur-satellite service allocations in the frequency band 1 240-1 300 MHz;

2. taking into account the results of the above review, to study possible technical and operational measures to ensure the protection of RNSS (space-to-Earth) receivers from the amateur and amateur-satellite services in the frequency band 1 240-1 300 MHz, without considering the removal of these amateur and amateur-satellite service allocations,” 

2. There will be constraints to parts of the band for amateurs as the studies have shown that there are two elements that minimise the risk of interference: 

  1. Frequency separation. The further the amateur transmission is from the centre of the RNSS band the lower the risk of interference.
  2. Power level restrictions. The lower the power of an amateur transmission the lower the risk of interference. 

An ITU-R Recommendation is under development in ITU-R WP5A which deals with amateur related work with the intent to provide guidance for administrations on constraints required on amateur service operation to protect the RNSS primary allocation. It is still too early to determine exactly what these constraints may be, if any, as there are various proposals on the table that are in discussions and have not yet been agreed upon. 

IARU will continue to 

• Minimise the constraints on the amateur services as far as possible.

• Retain the ability for as many of today’s applications to be able to continue as possible.

• Narrowband telegraphy and telephony and digital modes

• Wideband ATV (Digital)

• Work towards minimum disruption to narrow band activities.

• Maintain cross-region harmonisation of the narrowband section.

• Engagement will continue up to and including the WRC23 itself. 

The recommendation from the C5 committee is for the amateur community to sit tight and wait for the outcome of the next meeting of  ITU-R WP5A to see what the stance of the RNSS will be. 

Thanks to Barry G4SJH, who leads a team of competent radio amateurs from all three regions who are representing the interests of amateur radio in the various study groups for WRC23 Agenda Item 9.1.b. 

Sylvain F4GKR, the IARU R1 President spoke about the good working relationship that the IARU has in Europe with the authorities and the RNSS community and are working with them to find amicable solution. Amateur radio is well represented in a number of the member states in Region 1 which also has the highest voting power as there are more countries within Region 1 than in the rest of the regions. The IARU requests that amateur radio member societies develop a good working relationship with the Regional Telecommunications Organisations, Regulators and Communications authorities in their respective countries to make representations on the importance of amateur radio and to help influence their voting at the World Radio Conferences in favour of amateur radio.     

On Saturday afternoon just after lunch, I received a message to join an IARU meeting that was in progress. Of course I joined and it was a feedback session about the IARU Shaping the Future project that was given by Sylvain F4GKR. I have heard about the project and the following folk from the SARL are involved Hans ZS6AKV, Nico ZS6QL, Dennis ZS4BS and Rassie ZS1YT. The competition that was mentioned in the SARL news where the team lead by Guy ZS6GUY is one of the finalists, is part of this Shaping the Future project.


I believe that this is a great initiative being driven forward by the IARU, who of course are made up of member societies like the SARL who in turn are made up of members like you and I, so this is a project that is run by us, the radio amateurs. We are very privileged to have all the valuable frequencies that we have at no extra cost other than our license fees. Here is an opportunity to get involved and to give back to the hobby to ensure that it stays relevant and can continue to attract new radio amateurs in the future. From the information provided there is going to be some very exiting projects to get involved in. For more information take a look at the IARU Shaping the Future web pages at https://www.iaru-r1.org/stf/.
 

I found the feedback very interesting and the excitement and enthusiasm of our IARU President Sylvain F4GKRI, inspiring. 

What interesting project have you been working on or what exciting contact have you made on the VHF and above bands? 

Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za 

Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz. 


Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ.


Focus on VHF and Above 19 June 2022

 Audio  version

A couple of weeks ago I became aware of a problem that need not have been a problem if the band plan was followed. This week I want to talk about band plans, why we have them, why it is important to keep to them as well as keep up with the changes to the band plans.

 

The International Amateur Radio Union (IARU) (iaru.org) which was founded in 1925 represents the interests of amateur radio world wide. It has 160 member societies covering most territories. 

IARU World-map.jpg 

Countries with IARU Member Societies shown in yellow 

In South Africa, the member society is the South African Radio League (SARL).

Apart from advocacy at the ITU’s rule making World Radio Conferences, the IARU also establishes voluntary band plans for amateur use. These band plans normally extend across an ITU region. South Africa would therefore adhere to Region 1 band plans. 

These band plans are carefully formulated to take all interests of amateurs into account, and represent a compromise that hurts everyone equally. The considerations that went into making the band plan may not be obvious to you, and you may cause unanticipated interference if you decide to act contrary to the band plan. 

The bands allocated to amateurs are divided into segments for different uses according to the band plan. Typically each band has different segments set aside for CW, digital modes and phone. Some frequencies may be reserved for beacons, on which no other stations should transmit. Others may be reserved for particular purposes, such as satellite use or inter-continental DX. Although in most cases it is not a legal requirement to observe the band plans, courtesy to other operators should be sufficient reason to do so. 

In South Africa we have some additional bands allocated for our use that are not allocated in the rest of the region. An example of this the 8m band or the frequencies between 40.675 MHz – 40.685 MHz which has been allocated for amateur use for the study of propagation. 

These band plans are not cast in stone and do change and keep up with the developing technologies and ensures that there are frequencies allocated to allow for development of the hobby. With this in mind it is important to keep track of what the latest band plan is. For a full list of the current band plans for South Africa go to http://www.sarl.org.za/public/licences/bandplan.asp 

Should there be any doubt or questions, please do not just do your own thing. Rather ask and get a recommendation from the folk who do keep abreast with changes. If you have a query, you are more than welcome to send an email to vhfnews@sarl.org.za and your question will either be answered or referred to the right person who can advise. 

We all know that there is very little equipment available on the microwave bands and mostly we need to homebrew our own equipment. For the first time one of the big three amateur radio manufacturers are venturing above 23 cm. 

ICOM is busy working on a radio for the SHF bands. This project has been on the go for a while already and they decided to début the SHF-P1 Project Concept Model at Dayton Hamvention 2022. ICOM has documented two technical challenges to be solved. 

When trying to operate in the SHF band, cable loss will be the biggest bottleneck. For example, in the 5.6 GHz band, if a 30 meter long, 15 mm diameter high quality coaxial cable is used to connect between the antenna and transceiver, the cable loss will be 7.2 dB (at 5.6 GHz) and a 2 watt output from a transceiver will be reduced to 380 mW output from the antenna. 

Another challenge in the SHF band is the ultimate frequency stability requirement. For example, the IC-9700’s frequency stability is about ±0.5 ppm, but ±0.5 ppm stability in the 5.6 GHz band means a 2800 Hz deviation. It is completely outside of the IF filter and cannot be demodulated in the SSB and CW modes. In other words, the practical frequency stability for SSB and CW mode in the 5.6 GHz band is about ±0.01 ppm or less. This is an extremely difficult level to achieve with an OCXO (Oven Controlled-crystal Oscillator). 

So to solve the first challenge, long coax cables are not to be used.

The project team considered several ways to solve the cable loss issue. As a result, they decided to configure the RF module by directly placing it under the antenna and control it with a separate controller. 

A LAN cable is used to connect the controller to the RF module. By using this kind of cabling set up, only a small length of a coaxial cable (about 30-40 cm) is required between the RF module and the antenna. Thus, only minimal loss occurs. For example, even if the controller and RF unit are separated by 30 meters, the loss from coaxial cable is still minimized, due to the short coaxial cable length. 

When installing the RF module directly under the antenna, the issue of how to supply DC power arises. ICOM decided to adopt PoE (Power over Ethernet) technology that supplies power over a LAN cable. Since Ethernet twisted pair wiring is limited to 100 meters, it is possible to install the RF module at a location 100 meters away from your shack where the controller can also be. 

By adopting PoE technology, the connection can be made with a single cable, and the RF module can be installed more freely. Moreover, the PoE technology makes it possible to supply power with low power loss. Normally, if the power cable is extended to 20 meters, the voltage drop will be too large for a 10 watt transceiver, and it will not operate properly. With PoE technology, DC power loss can be reduced by raising the voltage and reducing the current, so it is possible to supply stable power, even if the cable is long. 

What about the second challenge, frequency accuracy and stability?

Even with a high-performance OCXO, frequency gradually changes due to temperature and aging. The annual deviation will be ±0.3 ppm and ±1.5 ppm in 10 years. At 5.6 GHz, the deviation will be as much as 8.4 kHz in 10 years. To solve this problem, they have adopted a method that uses a high-precision 1 Pulse-per-second (1PPS) clock signal from a GNSS (GPS) receiver to enable advanced frequency management. By synchronizing with this reference signal, the OCXO frequency can be compensated with high accuracy. 

The SHF band has many challenges, such as cable loss and frequency stability, so there are high hurdles for developing an SHF band transceiver. By clearing these issues, ICOM will continue to develop further, so that more amateur radio operators can challenge SHF band operation and discover its enjoyment and potential. 

What interesting project have you been working on or what exciting contact have you made on the VHF and above bands? 

Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za 

Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.

Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ. 


Focus on VHF and Above 12 June 2022

 Audio version 

Last week I reported about the coexistence between RNSS and Amateur Radio in the 23 cm band. 

In the last 2 weeks I have been thinking about this 23 cm challenge and information that I have come across has me thinking about the problem from a different angle.

Dennis ZS4BS sent me a photo mentioning a strange signal that was received by the Australian Parkes Observatory that peaked my interest to dig deeper. It goes about scientists at the Parkes Observatory in Australia and how they were for many years stumped by a strange signal that they received from outer space, only to discover that the signal was being emitted by the stations microwave oven every time it was prematurely opened. This is an interesting story and you can read more about it on the web.

https://spectrum.ieee.org/microwave-ovens-posing-as-astronomical-objects

I also came across a story on Southgate Amateur Radio News about a Noise

Cancellation video.

http://southgatearc.org/news/2022/may/noise-cancellation-part-1.htm#.YpsuoHWemUk

https://www.youtube.com/watch?v=8ybIoIhwgBQ

In this video what caught my interest was the fact that Michael WU2D was monitoring the noise in his shack with an old valve Knight-Kit "Star Roamer" Receiver and switched off his Watkins Johnson digital transceiver and the noise reduced. Amazing how even the relatively well built amateur transceiver can also be a source of noise. Admittedly it was an older generation transceiver. 

This got me thinking how much noise there is on the 23 cm band and how susceptible are the RNSS or GPS receivers, which are quite sensitive, to the rising noise floor. 

I would like to hear from the guys who are active on 23 cm how they experience noise floor within the built up areas and the rural areas. 

I would like to congratulate Tom ZR6TG for his initiative to encourage more amateurs to get active with satellites which at the same time encourages activity on the VHF and Above bands.

 Every month there is a challenge to be done to encourage amateurs to get active with Satellites.  In May the challenge was to decode satellite telemetry data. In June the challenge is to receive data from the QO-100 Satellite. Tom writes on the website hamsatsa.co.za

“For our new competition we are focusing on the Oscar 100 Satellite, more specifically the reception side of it. Amsat-DL has recently been experimenting with a Multimedia Beacon on the narrowband transponder. The multimedia beacon is part of the High Speed modem designed by Kurt Moraw (DJ0ABR). The high speed modem includes various modes of sending files, pictures and even do digital voice modes using FreeDV. Its a very exciting project and our competition involves getting an Oscar 100 station going and decoding the Multimedia Beacon.” 

Tom has also started an initiative specifically for satellite work called Satellite Manual https://www.satellitemanual.com/index.htm

Most of us know that there is a lot of information all over the internet about various aspects of our exciting hobby and part of our challenge is to collate this information so that we can use it when we do our own experiments and projects. 

Tom says in his introduction “While access to amateur radio satellites have been around for many years many hams are still unsure on how to get on the air and use these satellites. I’m still very much a newbie when it comes to amateur radio but I have a strong interest in playing with these satellites. This manual is a compilation of my own notes and information in the hope that it might be helpful for other hams to get on the air with satellites. This manual is still very much a work in progress and will be updated over time, but the idea is to focus more on the practical side of setting up your own station rather than going to deep into the theory.“

 Well done Tom.

The current challenge has spurred me to take a fresh look at my own QO-100 project that was shelved because I was chasing my own tail. I am now proud to say that I have the re-purposed DSTV dish set up and aligned and I’m able to receive the satellite. I have progressed from a simple RTL-SDR to a Pluto SDR and from Windows based software to Linux based software which runs much more efficiently on the old laptop that I use in the shack. Next up will be getting software running on a Raspberry Pi before tackling the transmission side of things. This is all plug and play up until now as I am still recovering from an eye operation and I cannot yet see well enough to perform micro surgery with my soldering iron. 

I would like to encourage more amateurs to step out of their comfort zones on HF and brave the exciting world of VHF and above. 

What interesting project have you been working on or what exciting contact have you made on the VHF and above bands? 

Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za 

Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.

 

Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ. 


Focus on VHF and Above 5 June 2022

 Audio recording

Kobus ZS3JPY alerted me to a post by Phil FR5DN from Reunion Island on the Earth Moon Earth (EME) Radio Communications Facebook Group. Phil says that this was his first reception on 10 GHz EME with a 80 cm TV offset dish, a TV LNB, a KR-400/KR-500 rotator, vertical polarisation and a simple SDR dongle. He received SP6JLW on CW on the centre of the band, and OZ1LPR a bit higher up. There was Libration spreading, but a good copy on headset. Phil goes on to say that he is amazed at the performance of such a small dish for almost a 800,000 km path.

 

Well done Phil. Phil used similar equipment that can be used to receive the QO-100 satellite as well.

 I have spent a large part of this week monitoring the Fourth SADC Preparatory Meeting for WRC-23. Just a week ago Hans ZS6AKV and myself sat in the 5th Meeting of the Technical National Preparatory Working Group 2023. Hans is the Rapporteur for Chapter 5 which covers Amateur Radio at the National Preparatory Working Group. So why is this important? 

There is a Resolution 774 of WRC19 that resolves to invite the ITU Radiocommunication Sector to perform a detailed review of the different systems and applications used in the amateur service and amateur-satellite service allocations in the frequency band 1 240-1 300 MHz; taking into account the results of the above review, to study possible technical and operational measures to ensure the protection of RNSS (space-to-Earth) receivers from the amateur and amateur-satellite services in the frequency band 1 240-1 300 MHz, without considering the removal of these amateur and amateur-satellite service allocations, and instructs the Director of the Radiocommunication Bureau to include the results of these studies in his Report to WRC-23 for the purpose of  considering appropriate actions in response to the resolution.

This is Agenda Item 9.1 topic b for WRC23. 

Prior to WRC19 there were two documented cases where radio amateurs caused interference to a RNSS receiver or as we know it a GPS receiver. Both incidents were in Europe. This resolution is as a result of this. 

There are ongoing studies in progress at the moment and it basically goes around the coexistence between the Radio Navigation Systems Services who are the primary users and the Amateur Radio and Amateur Radio Satellite Service who are secondary users. 

Work continues to develop the coexistence studies between the amateur services in the 23cm band and the radio-navigation satellite services (RNSS) operating across the band. New studies were submitted by France, China and the Russian Federation. 

The scale of the problem for the amateur services is becoming clear. For example, the studies predict that even a 10W 23cm band station could cause interference to RNSS receivers at up to 30km on the antenna main beam heading. Although the level of amateur activity and the density of users is quite low (compared to other more popular bands) the issue remains that from a regulatory perspective the amateur services are required to not cause harmful interference to RNSS services. 

The IARU summary report on the WP4C meeting can be found at

https://www.iaru.org/wp-content/uploads/2022/05/IARU-Report-from-WP4C_May-2022.docx 

Due to the ongoing studies there has not been any positions identified yet, but it is being closely monitored. 

There is strong Amateur Radio representation at all levels of government, sub-regional and regional telecommunications authorities with myself and Hans representing the SARL and the amateur community locally, I monitor the SADC meetings and myself and Tafa 6W1KI from Senegal monitor the ATU meetings on behalf of the IARU. We provide the IARU with a report regarding the position that the sub-regional and regional groups are taking regarding the issues that may have impact on Amateur Radio and our frequency allocations. While we are not allowed to provide inputs at the sub-regional and regional levels, we do lobby our local Department of Communications and Digital Technologies with whom we have a good working relationship. It is of utmost importance that we as radio amateurs keep abreast with international developments and do our best to ensure that we can continue to participate in this wonderful hobby of ours. 

Last week we discussed the importance of timing in digital modes. Let us now look at the other important factor with regards to digital modes and that is frequency accuracy which is the DF parameter you see on the digital modes screen. 

Most operators are used to using digital modes on HF on the FT8 or JT65a mode, because on HF you can clearly see the signal on the waterfall. You just click on it and the audio is on frequency.

But when we start moving to VHF and up the situation around frequency accuracy becomes a major factor. The reason is that you now work with signals that are almost not visible on the waterfall at all. You have to adjust your receive decode window to a very wide span and have to use a lot of computer processing getting a signal out of the noise.

Most digital modes cannot decode at all when the frequency is out of its normal specification of 200-300 Hz.

A lot of amateurs will say “my radio is spot on frequency” but sitting on the receiving side and hearing the actual signal and not being able to decode it can be frustrating for most VHF operators doing digital modes. 

So what do I do to make sure I am on the same frequency as the transmitting station?

In the software there are codes built into most of the modes to overcome this problem to make sure both stations are listening to the exact same frequency. Let us have a look at JT65, QRA64 and JT4 digital modes. These modes work very nicely.

When the QSO starts, in the first line you type in @800 or @1000 or @1250. It is your decision which audio frequency to use. The other station must just know what frequency you are using for calibration. Now because it is a single tone frequency it is easier to see on the waterfall and audible on the ear.

You now tune to the correct frequency by turning the dial on your radio to see the exact frequency on your screen. As long as you are within 200 Hz you are will be able to decode the signal, but it is better to get within 100 Hz as the modulated RF signals tend to distort drastically under certain path conditions in the VHF and above bands. There can be up to 200 Hz DF which is the difference frequency between the transmitting and receiving stations some times under worst conditions during a QSO.

The frequency error that exists on our hardware is still there and the error is especially noticeable when using digital modes and as one goes up in frequency the error increases. Those playing in the microwave bands or with QO-100 will have first hand experience of being way off frequency and the nightmare of trying to tune to the correct desired frequency. 

What we need to resolve this problem is a GPSDO or GPS Disciplined Oscillator. Some GPSDO devices are designed to put out a 10 MHz reference signal which is fine for test equipment, but does not really help us as our radios invariably will not have a 10 MHz reference oscillator, but one at another frequency and each model and manufacturer uses a different frequency. 

There are however GPSDO available that you can program to a frequency that you desire, like the Leo Bodnar Precision GPS Reference Clock. This will however set you back at least 150 GBP (Approx R3,000.00) excluding shipping and fees.

 

Leo_BodnerGPS-CLOCK.png 

http://www.leobodnar.com/shop/index.php?main_page=product_info&cPath=107&products_id=234 

There is also a mini version available that is also much cheaper at around 86 GBP (Approx R1,700.00) excluding shipping and fees.

 

 

 

https://www.sdr-kits.net/GPS-Disciplined-Reference-Oscillator-for-DG8SAQ-VNWA

 

Another solution is to use a RF Zero which will set you back around 400 DKK (Approx R910.00) also excluding shipping and fees. There are options that you may want to add such as filters and attenuators as well which will of course increase the price and you will need to also provide a box for it to live in.

 

 

https://www.rfzero.net/shop/ 

Of course you would also need to figure out how you are going to connect the GPSDO to your radio, but that is normally not a big challenge.

 A lot of the amateurs participating in the HamSCI activities also add GPSDO to their HF radios in order to more accurately measure the shift of the 10 MHz time signals that are being monitored.

What interesting project have you been working on or what exciting contact have you made on the VHF and above bands?

 Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za. 

 Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz. 

Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ

 

Focus on VHF and Above 22 May  2022

Audio Version

This week  there are two entries of remarkable 40 MHz contacts on the website of John EI7GL. 

The first one was on 16 May when there was a 40 MHz contact between S50B in Slovenia and PY2XB in Brazil (approx 10 000 km) and LU5FF in Argentina (Approx 11 300 km).

The second one on 18 May was between WM2XEJ and CE3SOC in Chile, a distance of 7562 km. 

On Wednesday morning 18 May Bernie ZS4TX worked Yuri UT1FG/MM 2M FSK441 in JG36pi, ~1970km.  Bernie says that they tried later in the day when Yuri was around 2024 km away but only partial decodes were received at both ends.   

On Thursday evening at 20:07 UTC Fred PY7ZZ completed a 6m FT8 contact with Barrie ZD7MY on St Helena Island. 

The SARL VHF/UHF Digital contest has also been on this weekend and looking at the 46 Long Distance VHF/UHF WhatsApp group, there has been at lot of activity being reported. 

This week we are going to talk a little about low cost hardware that a beginner can play with on VHF and Above. 

In the early days most radio amateurs built their own AM transmitters and some even tried their hand at building communication receivers. When the solid state era arrived the Japanese shrunk all mode transmitters and receivers into a single unit and called it transceivers, all based on transistors and chips, which made it difficult for amateurs to emulate so it became far easier to purchase the finished professional version. 

Let’s face it, Amateur Radio equipment is very expensive, especially for the beginner who has just obtained a license. Multi-mode transceivers for the VHF and above bands have also become scarce.

We also sit with the situation that the older transceivers were not designed with the modern digital modes in mind. The design and specification of the reference oscillators were great for wider bandwidth voice modes, but are too unstable for the current digital modes and of course the higher you go up in frequency the more critical this becomes as well. The other problem is when that older multi-mode transceivers built in the ‘80s or ‘90s goes faulty, then you will be very lucky if you can find any components to fix the radio with. 

So what are the alternatives today for the new radio amateur who simply cannot afford modern day multi-mode transceiver that costs the price of a small car? 

I believe the answer is to home-brew your own transmitters and receivers.

With modules around like GPS disciplined oscillators, SDR transmitters and receivers, single board computers and free software you can go a long way. Add to this a power amplifier and some decent antennas and you can easily put out tens of Watts of power. 

You can start with a SDR receiver dongle, like the RTL-SDR V3 receiver that operates from 500 kHz to 1.7 GHz and costs around R550 locally or even the lower cost RTL2832U FC0013B SDR receivers with a frequency range of 22 MHz to 1.1 GHz and costs around R320. 

Add to the hardware some home built antennas and some freely available software and you are on your way to building a receiving station for the HF and VHF and Above bands, depending on the SDR receiver that you have purchased. There are of course more expensive SDR receivers and even SDR transceivers that are available, but they may become out of the reach of the beginner, depending on what your budget may be.

Believe me there is such a lot of things that you can do with a SDR receiver.  

How about a low cost transmitter? Well that is also possible using a program on github written by F5OEO. The program is rpitx and according to github can transmit any frequency between 5 kHz and 1500 MHz? Yes, you guessed it, rpitx is a utility that runs on any Raspberry Pi model. Again according to the author’s github page rpitx can run on the model B, B+, PI2, PI3B, PI3B+, PIZero or  PiZerow. It is of course low power and requires the necessary low pass filters because the GPIO pin that you control has a square wave output and you need to filter out the harmonics. 

Yes, it is true, you can turn a Raspberry Pi into a transmitter. I have twice seen a demo being done by Anton, ZR6AIC where he demonstrated using SDR receiver connected to a Raspberry Pi and then using software like GNUradio that received a signal on 70cm and re-transmitted the audio on 2m. 

Go and have a look at the blogspot of Anton ZR6AIC  http://zr6aic.blogspot.com/ and have a look at some of the stuff he is playing with. Look at the satellite transponder he is working on. 

You can also spend some more and get a higher performance Lime or Pluto SDR which also has a greater frequency range.

With this type of SDR you can easily build your own QO-100 satellite station or a 70 MHz to 6 GHz transceiver. Go and look at the Langstone transceiver at https://g1lps.com/langstone-tranceiver-vhf-ghz/ or https://wiki.microwavers.org.uk/Langstone_Project for more information. 

You can even venture into Digital Amateur TV and build yourself a Portsdown 4 DATV system. Take a look at https://wiki.batc.org.uk/Portsdown_4 

So, the possibilities are endless. 

What interesting project have you been working on or what eciting contact have you made on the VHF and above bands? 

Please send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za 

Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.

Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ.