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VHF+ UHF+ MICROWAVE NEWS - FOCUS ON VHF with ZS6YZ 20 August 2023

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Focus on VHF and Above 3 December 2023

Audio version

This past week there has again been some excellent long distance communications experienced along the West Coast of South Africa. This has been due to the very good tropoducting conditions along the West Coast.

Looking at the Hepburn charts for the coming week it looks like the later half of the week will again produce very, very good tropo conditions along the West Coast.

I have found an announcement on the HamSCI.org website of the publication of the latest peer-reviewed paper.

Dr. Nathaniel Frissell W2NAF, Lead Organizer for HamSCI and assistant professor of Physics and Engineering at the University of Scranton, has announced that its latest paper, "Heliophysics and Amateur Radio: Citizen Science Collaborations For Atmospheric, Ionospheric, And Space Physics Research And Operations,” has been published in the peer-reviewed journal Frontiers of Astronomy and Space Science*.

The paper reviews the history of amateur radio and science back to 1912, with the greatest emphasis on results that have emerged in the last decade. Dr. Frissell stressed the importance of this work by noting “This paper is the result of expanding and combining two white papers submitted to the National Academy of Sciences Decadal Survey for Solar and Space Physics (Heliophysics) 2024-2033, which helps the United States to establish research priorities for the next ten years. As such, this paper not only reviews past results, but also provides recommendations for amateur radio - professional science collaborations in the future from both technical and community-building perspectives.”

*Frontiers in Astronomy and Space Sciences is a multidisciplinary journal that unravels the mysteries of the universe and explores planetary science and extragalactic astronomy in all wavelengths.

This afternoon Hans ZS6AKV and myself will be preparing a stand at the Science Forum.

The Science Forum South Africa will be held from 6 to 8 December 2023 at the CSIR International Convention Centre in Pretoria, South Africa. The Forum serves as a large, open, public platform for debating the science and society interface.

The Forum is co-hosted by the South African Department of Science and Innovation (DSI) and the Science Diplomacy Capital for Africa (SDCfA) initiative.

Amateur radio is a unique hobby and often referred to as the greatest scientific hobby on earth and it is appropriate that AMSATSA and the SARL participates and showcases our hobby and the Science in Amateur Radio. We will be displaying some of our scientific projects that we radio amateurs are working on, namely the Africube, Inland Tropospheric Research and the Beacon Project, the Noise Monitoring Project and the AMSATSA YAGI antenna.

You can find more information at https://www.sfsa.co.za/

I have also found an interesting article written by John Corby VA3KOT with the title “Making Math Easy for Ham Radio Experimenters”.

In this article John writes that while there are those cheque book amateurs there are also those of us who are experimenters and it is inevitable that while playing with cores, coils, wires and wireless there will be a need to do some calculations. For some this maths that we were exposed to while studying for our Amateur Radio license may be easy, but not for others. There is a tool out there that can help us and it is called a spreadsheet. Well, you may whip out your cellphone and say that it is not necessary as you have this handy application that can do all sorts of electronic and RF calculations.
I can assure you that you will soon find the limitations of those cellphone applications. Like John, I have a number of spreadsheets that I have set up formulas to do calculations on the fly, converting power between Watts and dBm, calculating current limiting resistor values for LEDs, calculating free space path losses, capacitances, resistors and inductors in series and parallel, to name a few. Yes, you do require some skill to initially master the formulas used in a spreadsheet, but once it is accomplished then the spreadsheet will compute the answer way faster than any application on a cellphone or even using your trusted scientific calculator of you can remember the formula.

Spreadsheets make it so easy to change input variables on the fly and immediately see the end result.

What interesting project are you working on or have you made an exciting contact on the VHF and above bands. Tell us about it at VHF News by sending 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 September 2023

Audio version

The really great news is that on Tuesday and Wednesday there has been great TEP openings on 6 m, resulting in contacts on FT8, CW and SSB. Even the V53SIX beacon which as a CW beacon was heard.

The V53SIX beacon is running on Rossing mountain which is to the East of Swakopmund, Namibia, at grid locator JG77II. The beacon runs 10 watts into a vertical antenna and after each transmission the antenna switches to a two element yagi and so on. The allocated frequency is 50.495 MHz CW, and the Yagi points North .

The vertical antenna is a Diamond CP62 it has a gain of 5.5dBi the Yagi is Diamond A502HB with a gain of 6.3 dBi

Well done to everyone who has been active during these openings.

Watching the Hepburn charts also shows the possibilities for some good tropo conditions over the South Atlantic between the West Coast of South Africa and Namibia and the East Coast of Brazil.

Hepburn_Chart_South_Atlantic_1800UTC_18September2023.jpeg

We are holding thumbs for some possible contacts over the next couple of days.

Continuing with some of the proposals put forward to the IARU General Conference in November.
The next proposal I want to highlight is ZL23_C5_08 with the title “OTA (On-The-Air)-Center of Outdoor Activity”. This proposal was also proposed by Kurt Baumann, OE1KBC. Kurt says “ When it comes to OTA, the new generation is increasingly focusing on outdoor activities. For example, SOTA, POTA, WWFF, LHOTA, COTA and many others have all been on the rise in recent years. The connection of amateur radio as a hobby, outdoor activities and very moderate competition drives these activities.”

Some background to this proposal. Unlike here in South Africa where there is very little VHF/UHF activity, in Europe there is so much activity that the allocated band is too small for all the activity and there is always jostling for a space to operate and the idea behind Kurt’s proposal is to make some space available for the outdoor type of activities which are mostly done with low power and modest equipment and competes with the larger and stronger home based stations.

Kurt says “The reason for this request is not to separate the different activities but to create space for special activities so that differing activities do not collide and reduce the fun factor of the hobby. The general call frequencies should be kept free for general topics. The use of the general calling frequencies is not practical in outdoor OTA operations since various weather conditions allow only limited operation of the radios. Also, QSOs are usually very short and thus general calling frequencies are blocked.”

Kurt proposes that “A resolution should be passed including a listing of center-of-activity frequencies in the VHF manual. Proposal: 3 frequencies each for VHF and UHF are sufficient.”

This proposal does not affect us here in South Africa. I wish we had such a problem locally that we needed to address.

The next proposal is ZL23_C5_26, which is titled “Avoid Mixed modes (digital-analog) in contests” and is proposed by Alessandro Carletti, IV3KKW who is the C5 Contest Working Group Chairman.

The background to this proposal stems from the Virtual General Conference 2020 where the C5 Contest Working Group, after an accurate analysis of the use of the spectrum during any mixed mode contest, has decided to split the analogue (phone-cw) and other digital modes categories in any IARU Region 1 VHF+ contest with the creation of a new contest calendar with VHF+ “Only MGM” Contests and VHF+ “SSB-CW” Contests in separate dates and times.

The C5 Contest Working Group recommends avoiding organising any contest where is permitted either the use of digital modes and analog modes (phone-cw), with the main goal to increase the use of the spectrum efficiently during any contest activity.

In particular, it is highly recommended to align bands and modes usage during all the Subregional Contests which are part of IARU Region 1 as in the following list :

• 1st weekend of March : 1st Subregional contest 145 MHz & Up

• 1st weekend of May: 2nd Subregional contest 145 MHz & Up

• 1st weekend of June : Microwave Subregional Contest 1296 MHz and up

• 1st weekend of July: 3rd Subregional contest 145 MHz & Up

• 1st weekend of September : IARU Region 1 145 MHz contest

• 1st weekend of October : IARU Region 1 UHF & Up Contest (435 MHz & up)

• 1st weekend of November : Marconi Memorial Contest 145 MHz (Only CW)

Again, these changes will not have affect us here in South Africa, but you will understand the challenges in Europe with the high density of the amateur population and the keenly contested contests.

Most of the remaining proposals also have little affect on us here in South Africa, but are mainly amendments to the contest rules regarding the submissions of logs and by when. There are also submissions regarding updates to the VHF Manual, the format of the VHF manual and about the IARU Region 1 ATV or Amateur Television Contest.

You are welcome to review all the General Conference documents at the web address https://conf.iaru-r1.org/documents/

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

Focus on VHF and Above 10 September 2023

Audio version

Today we are going to look at the proposal document ZL23_C5_09 with the title “Projects with great hype for the radio community” and proposed by Kurt Baumann OE1KBC, who also proposed the two papers discussed last week which were about allocating space in the band plans for wideband data modes and experimentation.

Kurt asks the question “Which are the projects with a potential to be widely adopted?” and mentions the following:

“When looking at projects that the amateur radio community widely participated in over the long term, it becomes evident that similar approaches have led to success again and again. I would like to list a few key points here:

· Display of own activities in dashboards

· Free access to necessary materials, software, documentation

· Participation in the shaping of the project structure

· Cost factor of the necessary materials

· Replication must be simple and reproducible

· Test environments available 24/7—even if no test partners are available

One well-known example of high dissemination of a project approach are the worldwide platforms for digital voice modes. It is precisely in this project that the cornerstones listed above can be found. The cost factor, however, is closely related to one’s own benefit from the project. The development of HOTSPOTs in the Digital Voice Modes project showed that self-construction/reconstruction is (at least in parts) a very important factor. The sole use of ready-made rigid systems, meaning the use of repeaters, was not adopted to the extent of today’s use of ready-made and self-built HOTSPOTs. Having a say in the functionality at the structure level with your own commands is also a very essential part of a successful project. The utilization of reflectors that can be freely switched by users ensured that the IPSC2 project remains an exciting one to this day. Together with other similar project ideas free the user from a feeling of being stuck in a rigid corset and thus having to leave the topic aside again.”

When Kurt mentions hotspots, it is not only DMR hotspots, but digi-peaters and I-gates as well. It is the interface between RF and IP.

To give some background Kurt says “Making projects more attractive through collaboration.

Our common goal should be to create larger and more visible platforms in the regional and national societies as well as in the committees of the IARU for the collection and circulation of information as well as for the documentation of project ideas. This is an important part in the dissemination of projects that should reach a large base. The APRS project (FSK, RPR, LoRa) and also the projects focussing on digital voice modes (IPSC2, BRANDMEISTER, and many more) have thus reached a global level and common benefits. We should, however, ensure the circulation of even more project ideas and strengthen the IARU community.”

Kurt says that the key points of the proposal are: “It is important to offer a variety of projects.

The diversity of the projects offered should—I would even go as far as saying must—be an essential approach. We should therefore place great importance on the support of working groups that take up new project ideas and prepare them for the community. We see very good approaches in the IARU Region 1 and in many member associations that are already making efforts to advance project funding. In various IARU working groups, the STF “Shaping the Future of Amateur Radio” topic has already been placed on the agendas and budgetary items are allocated to it.”

Kurt’s recommendations are to provide project development support.

Kurt says “Starting a project is often time-consuming, but since this is our hobby that’s pretty much a non-issue. On the other hand, it is also associated with costs. Project funds such as STF “Shaping the Future of Amateur Radio” started in IARU and/or innovation and project funding from member associations are very important to this end. When allocating resources from the project funds, it is essential to comply at least with the points listed in the introduction to ensure the projects are suitable for a wide range of uses.”

Kurt’s suggestion for this is to put the “Promotion of project ideas” on the agenda of the committee meetings (and interim meetings) on a regular basis as progress in technology is advancing rapidly.

Kurt goes onto say that this paper will be followed at the Conference by a keynote presentation and documentation on “Lora MeshCom 4.0” clearly explaining the hype mentioned in the title.

I have previously discussed the LoRa MeshCom 4.0 project that was showcased at this year’s Friedrichshafen Ham Radio Convention in Germany as well as a number of other projects such a New Packet Radio (NPR) and many more that I have discovered over the last couple of months. Yes, months not years.

As technology advances there are just so much more opportunities for new and exciting projects in the world of amateur radio.

In the 1920’s we were called Experimenters and only later Radio Amateurs. Everything that we played with we built ourselves. Many of the components were built by us as well. Then we laid our hands on war surplus equipment that we re-purposed, we purchased components, home-brewed equipment with these components and then the components became so small that most of us can barely see them. We purchased ready made equipment that became more powerful and sophisticated and so expensive that we almost cannot afford them. Now we can purchase relatively inexpensive modules and string them together with some software controlling them and build efficient innovative low powered systems. I think going forward we should again be called experimenters.

We older amateurs may feel lost in this new world, but what a playground for the youngsters following in our footsteps. We need to captivate their imaginations and guide them into this ever evolving and exciting world of Amateur Radio.

This proposal certainly gets my vote.

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

Focus on VHF and Above 3 September 2023

Audio version

There has again been no significant VHF and above communications that has been reported this last week.

I found a post on the blogspot of Mikel EA5IYL where he speaks about the knife edge effect on 2 m and 70 cm.

According to Wikipedia (https://en.wikipedia.org/wiki/Diffraction#Knife_edge) the definition of Knife Edge is “The knife-edge effect or knife-edge diffraction is a truncation of a portion of the incident radiation that strikes a sharp well-defined obstacle, such as a mountain range or the wall of a building. The knife-edge effect is explained by the Huygens–Fresnel principle, which states that a well-defined obstruction to an electromagnetic wave acts as a secondary source, and creates a new wavefront. This new wavefront propagates into the geometric shadow area of the obstacle.”

Mikel says “Studying the 2 m and 70 cm repeaters I can excite every day from home that is, without the help of tropospheric ducting, I have found that about half of them are behind rather tall mountains; I suspect the knife-edge effect or diffraction on the crests of these mountains is the reason.”

Mikel posted a picture of a path profile with a 1050-m peak at ~40 km from his QTH which is possibly the reason why he can reach the repeater at 160 km from his QTH every day.

Knife_Edge_Example_1.png

Mikel mentions a second example as well where he reaches 2 m and 70 cm repeaters at a summit of 1048 m, 52 km from his QTH, yet there is ~1400 m ridge 38 km from him.

Knife_Edge_Example_2.png

Mikel goes on to say “So, perhaps, 2 m and 70 cm ham radio is not only about line-of-sight, tropospheric ducting, or satellites. You can be surrounded by mountains and still reach far with their help.”

This is very true and works on the higher bands as well as I mentioned a while back that when ICOM were testing their IC-905. An experiment done in Japan on 5600 MHz and 10 GHz using the ICOM IC-905. With a power output of 2 W and 1 W the staff of ICOM have made a remarkable contact over a distance of around 25 km with line of site obstructed by a mountain range.

Keep this is mind when playing with VHF and above that the range of your propagation path is not limited to line of sight. It can go way further depending on your location.

This week we continue looking at some more of the VHF+ proposals that has been submitted for the 26th IARU Region 1 General Conference to be held in Zlatibor, Serbia, from 1 to 4 November 2023.

Document ZL23_C5_10 with the title “SHF 23CM wideband for SDR ACTIVITY” is similar to the document discussed last week to allocate a portion of the 23 cm band to experiment with wideband modes. This document was submitted by Ing. Kurt Baumann, OE1KBC, and Mike Zwingl, OE3MZC.

Likewise document ZL23_C5_11 with the title “UHF/SHF activity with more than 250kHz bandwidth” also proposes changes to the 70 cm band to allow for data transmissions with bandwidths greater than 250 kHz. This document was also submitted by Ing. Kurt Baumann, OE1KBC.

Both these documents are motivated by the numerous amateur radio projects like ICOM-DD-Mode and the IC-9700, OpenSource projects (OSMOCOM) with applications for GSM/LTE and LoRa spread spectrum such as MeshCom 4.0 that could be observed in practice and with numerous presentations at HAMRADIO 2021,2022 and 2023, the Friedrichshafen Ham Radio Convention in Germany.

How many of the local hams here in South Africa are currently experimenting or considering to experiment with some of these modes and devices? I am sure that you will support the bandplans being amended to make space for these exciting projects.

Let me know what you think at vhfnews@sarl.org.za.

Next week I will present yet another proposal firmly supporting amateur radio innovation.

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

Focus on VHF and Above 27 August 2023

Audio Version

On Friday, according to the Hepburn charts, conditions to St Helena Island looked good and Garry ZD7GWM had the beacon running, but unfortunately the conditions did not allow for any communications. Saturday and Sunday, today, the conditions also looks promising for possibilities between St Helena Island and Brazil.

Also on Friday the Hepburn charts showed conditions along the East Coast to Reunion Island started picking up and Phil F R5DN had his beacon on, but also no communications.

The IARU has published the documents submitted for the 26th IARU Region 1 General Conference to be held in Zlatibor, Serbia, from 1 to 4 November 2023.

Committee C5 which is the committee that deals with VHF and above matters has published the 31 documents submitted for the conference. Other than the Agenda and document list, are the chairman’s report and the reports from the various coordinators and working groups within the C5 committee there are information documents and documents that require a decision by the VHF+ committee.

The SARL also submitted an information paper to the conference with the title “Next Generation beacon for Tropo propagation research” which provides information on the SARL Beacon Project that was authored by Nico ZS6QL, Brian ZS6YZ and Hans ZS6AKV.

In the next couple of weeks I will review some of the documents, especially the ones where a decision needs to be taken on that may have an effect on what we do locally on the VHF and above bands. We need to remember that although VHF and above is mostly line of sight type of communications, there are propagation modes that does allow for long distance communications to take place and there needs to be coordination on these bands.

The first one that caught my eye was ZL23_C5_16 Increased Flexibility in 430 MHz band plan. This was submitted by John Regnault G4SWX, the RSGB VHF/UHF Manager.

John’s motivation is:

The 430MHz band plan has evolved over many years with changes driven by C5 papers proposing allocations for new modes and making changes with modes that had fallen out of use. The resulting overall band plan has become a patchwork of these changes which with the many sub-regional changes, mostly in repeater spacing, leaves many users confused.

There has been a rapid increase in digital modes, hotspot nodes, personal gateways and low power repeaters. There have also been some deployments of wider bandwidth digital data modes including New Packet radio (NPR) and LoRa.

In the next few years, it is likely that more voice and data digital modes will evolve where users will want to know where these modes are best used. In the UK there will be a liberalisation in the licensing of low power hot-spots, repeaters and gateways. In addition, recent years have seen a decline in 430MHz narrowband CW/SSB/MGM activity with much of the CW activity taking place mixed with SSB activity.

This proposal also recognises that the increasing use of Low Power Devices (LPD) around 433MHz has increased interference to amateur communications and has caused a tendency for amateurs to move away from this part of the band.

John also states that It also should be pointed out that the 430MHz band plan on the IARU R1 site:

• https://www.iaru-r1.org/wp-content/uploads/2021/03/UHF-Bandplan.pdf

differs in several places from the band plan published in the VHF Managers Handbook:

• https://www.iaru-r1.org/wp-content/uploads/2021/03/VHF_Handbook_V9.01.pdf

Finally we note that the frequencies cited for the edges of the sub-bands correspond to a 25kHz channel spacing rather than 12.5kHz which is commensurate with a 12kHz maximum bandwidth.

John’s proposal is:

It is proposed that the 430MHz band plan is simplified to both accommodate existing and future sub-regional changes; and to increase the flexibility in deploying new modes and personal hot-spots, repeaters and gateways.

The revised 430MHz band plan that we propose also makes it clear that in the 430.000-432.000MHz, 433.600-434.00MHz and 438.000-440.000MHz that all modes are permitted with no maximum bandwidth restriction.

The revised band plan recognises the widespread use of 12.5kHz spacing for channelized modes.

To recognise the changes in narrow-band operation it is proposed to make 432.000-432.400 2700Hz maximum bandwidth CW/SSB and MGM. This change also recognises the increasing use of Q65C for EME and weak signal contacts.

Entries for PSK31, 432.088MHz and EMGM 432.491-432.493MHz should be deleted, as any use of these modes is acceptable within other parts of the 430MHz band.

This is an amendment that I do support and it has been spoken about in the previous virtual general conference that bandwidth limits needs to be removed to allow for the future experimentation with higher bandwidth modes, not only in the 70 cm band, but in other bands as well.I wonder if there are any views for or against such a change. Let me know what you think at vhfnews@sarl.org.za.

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