South African Radio League Home Page

VHF+ UHF+ MICROWAVE NEWS - FOCUS ON VHF with ZS6YZ 21 July 2024

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 21 July 2024

Audio Version

On Saturday I had the privilege to attend an AMSAT SA meeting at the National Amateur Radio Centre in Johannesburg. The meeting as arranged to coincide with the visit of Burns Fisher WB1FJ who has been visiting in the country with a choir group that he is a member of and he took some time out before returning home to give a presentation on some of the developments taking place within AMSAT North America with their cube satellite projects.

Burn Fisher was presented with a certificate of appreciation for his support to the AMSATSA Space symposiums.

It was a very interesting and interactive presentation and an opportunity to get some first hand information from a person who has been very involved with AMSAT NA and has written most of the software that is controlling the amateur satellites that are presently in the air.

After a lunch break Anton ZR6AIC gave an update on the redesigned power module for AfriCube and the process that was used to redesign the power module. Also a very interesting presentation and I was absolutely fascinated by all the work and research that was gone into the design of the power module to ensure that it is robust enough for space flight and can provide for the power requirements of the satellite. There were so many questions and criteria that needed to be looked at and he has done a truly remarkable job at redesigning the power module.

Thank you Burns for the fascinating overview of the work that is taking place within AMSAT NA to get more amateur satellites into the air and well done Anton with all the work that you have put in so far with AfriCube.

It was also great to see a number of the AMSAT SA stalwarts again for the first time face to face in a number of years. I truly enjoyed the outing.

While there are not many amateur satellites that are orbiting at the moment, the International Space Station is still very much active and on the air with both a FM repeater and an APRS Digipeater that is active.The FM repeater frequencies on the ISS is uplink 145.900 MHz with a 67 Hz tone and the downlink frequency is 437.800 MHz.

The APRS Digipeater is on 145.825 MHz.Burns noted that occasionally instead of a repeater you will find a live astronaut on the repeater frequency.

So what do you need to be able to make contact with a satellite or the ISS?

You can go to the AMSAT website and look at the status of the satellites as well as recent reports of which satellites have been heard. On this same website you can also find more information about the particular satellite that you are interested in. For example, whether the satellite requires any CTCSS tones that need to be used in order to activate the transponder and to talk through the satellite.

First you need to find out which satellites will be passing over your location and when. There are free software programs like Gpredict which you can install on your computer and once set up you will be able to select which satellites you want predictions for. It will be preferable if you have an internet connection over which you can download the updates of the Keplerian Elements. Alternatively you can enter your location on the AMSAT website and get a prediction of when the satellite you are interested in will be overhead.

Now that you know when the satellite that you want to use will be passing overhead, you can start getting ready to see if you can receive it. You can make a successful satellite contact using a dual band hand-held radio with an antenna other than the rubber duck antenna normally supplied with the radio. A telescopic whip antenna is better to use. The AMSAT SA YAGI is an ideal antenna to use and you can more information about the antenna at https://amsatsa.org.za. This antenna was specially designed for satellite use.

It would be useful if you are familiar with you radio and know how to program split frequencies into your radio’s memory.

The satellites transmit with low power, and typically in the region of 250 mW. You therefore need to disable the squelch on your radio to be able to hear these weak, but readable signals.

Next you need to set up your radio to be able to tune for the Doppler effect.

You need to start listening to the satellite 10 kHz above the centre frequency. This will allow you to hear the satellite sooner and clearer. As the satellite passes overhead you will hear that the downlink signal will start to get scratchy and then you need to tune down in 5 kHz steps to improve your reception. You need to keep tuning down in frequency as the satellite passes ending up around 10 kHz below the centre frequency at the end of the pass.

If you are using a whip antenna, then you must not hold your antenna upright. If you are facing the direction in which the satellite will appear then you will get better results if you tilt your radio and antenna down towards the ground so that your antenna is more or less perpendicular to the satellite. Should you have your back to the approaching satellite then your antenna needs to be tilted upwards at about 45 degrees, again so that your antenna is perpendicular to the approaching satellite.

If you are using an Yagi antenna, then you will need to point it at the approaching satellite and track the satellite as it passes overhead to maintain a good received signal.

At this stage it would be a good idea to first practise tracking and tuning for the Doppler effect before attempting to transmit. You should also familiarise yourself with the quick voice procedures used when making contacts via the satellites. Satellite passes only last 7 - 15 minutes so there is no time for rag chewing.

You can also program successive memory channels on your radio with the required frequencies and the changing receive frequencies to account for the Doppler effect. This will make it simpler to tune your radio. You now just need to keep pressing the memory up or down button to keep you radio tuned to the satellites changing frequency.

Right, now you have everything set-up and you have practised tracking the satellite and tuning for the Doppler effect and you are ready to make your first contact.

Remember, if you cannot hear the satellite, then do not transmit. When you hear the satellite and there is a QSO in progress wait for a break and then announce your call sign and grid locator using the international phonetic alphabet.

On FM satellites it is not necessary to call CQ. You exchange call signs and grid locators when there are many stations on a pass. If there are few stations trying to work the satellite, then you can exchange more information like name, city and province.

Hope that this will help you make an exciting contact on a satellite or the ISS.

There are also times when the ISS transmits SSTV or Slow Scan TV images that can also be exciting to receive. This however needs a little more work and you need to connect your radio to a computer as well, but more about this in a later programme.

Yesterday evening, Dick ZS6BUN announced on the 46 Long Distance WhatsApp group that he would be on 70 cm this morning from about 07:30. There were at least two replies from the group who would be in the air as well. I would be interested to know how it went and whether any contacts were made.I am not aware of any other VHF and above activity.

How about you contributing to the program by telling us about the exciting long distance contact on the VHF and above bands or are you working on a project 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 23 June 2024

Audio version

I had a look at the https://spaceweather.com/ and saw the following at the top of the page:

“This is an AI Free Zone! Text created by Large Language Models is spreading rapidly across the Internet. It's well-written, artificial, frequently inaccurate. If you find a mistake on Spaceweather.com, rest assured it was made by a real human being.”

It is bad enough trying to filter out the garbage returned by search engines on the internet, but now we need to filter out the garbage generated by robots as well. It is bad when websites now tell you that they are not driven by AI or Artificial Intelligence.

I am finding that people are now implementing AI technology everywhere and just like we experience on Social Media where people just forward anything that they receive without verifying the facts or even fixing the blatant errors. Virtual meetings are being recorded and AI being used to transcode the meeting and immediately after the meeting a transcode of the meeting is distributed.

An example. On Thursday I attended the City of Tshwane Disaster Risk Management Advisory Forum. Less than 20 minutes later the AI transcoded transcript that we received said “ The City of Toronto Musical Disaster Management Advisory Forum met to discuss updates and action plans”

But, that is not all, the organisation that provides the “free” transcript also tries to hook you to pay good money for a lousy service and wants to tell you how to run your meeting and at no extra charge you get spammed by other AI engines also on the band wagon trying to sell you their transcription services all just because you volunteer to help make a difference and attended a virtual meeting.

I myself have used AI to generate a transcript of a recording that we have in the SARL 100 Project archives, but I do not just accept that the transcript is correct and send it off. I review the transcript while listening to the recording to fix any mistakes that the AI engine has made and I do not need to pay to use the AI engine either. I must also say that the AI engine that I used was very accurate in the transcription that was produced.

AI is very useful and can up your productivity tremendously and there is so much that we can do with AI, but we still need to apply our minds and we definitely need to learn to control this beast.

There is one social media platform that is not driven by AI yet, and may it never be. It however does sometimes make use of the internet, but the internet is not necessary. In fact it works just as well with or without the internet. It is also spam free and there is no commercial advertising either. What is it?

Looking through the Loggers Bark which is the club magazine of the W7DK Radio Club of Tacoma they have what is called an Elmer Board which is a list of members skills or areas of interest along with corresponding names of club members who are willing to be Elmers and guide the new ham.

This is something that is seriously lacking in the hobby here in SA. I know that there is a wealth of knowledge and experience amongst us, but there are so few of us willing to spend the time helping the new guys & girls to get going.

This is the first time that I have seen this magazine. You can find it at https://static.qrz.com/w7dk/June2024-QRZ.pdf

There is still very little activity on the VHF and above bands other than the the repeaters carrying the bulletins, the morning porky net, the odd call that mostly goes unanswered and don’t forget the PTT and repeater testers. In fact there seems to be little activity in general within the hobby. Why?

Listen to Onno VK6FLAB

Foundations_of_Amateur_Radio_Experimentation_is_about_Failure.mp3

So what is the social media platform that is not driven by AI yet?

It is called Amateur Radio, so let’s play radio, experiment and have fun.

Have you made an exciting long distance contact on the VHF and above bands or are you working on a project 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.

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

Focus on VHF and Above 16 June 2024

Audio version

It has been a little dry as far as VHF and above activity goes.

Beacon update

An update regarding the beacon project, this week Danie ZR6AGB and myself took a trip to Alberton to collect the antennas that were built by Deon ZS6RFI from RF Industries. We specifically chose these antennas due to their robustness which is what we need at an exposed site in the Karoo. At this stage all the RF related hardware has been purchased and is ready for assembly and testing. Next up is the specification of the solar power system and then all the security related items.

Hamnet

Apart from discussing the problem with my Land Cruiser that I use as my mobile/field station, Danie and I also discussed some HAMNET related topics, one of which is a suitable frequency for emergency use that will allow reasonably good simplex coverage across the province. I’m currently doing some coverage plots for both 10 m and 6 m both from my QTH which is behind the lump of rock called the Magaliesburg and from a position on top of the Magaliesburg where one could place a temporary cross band repeater if required. Danie ZR6AGB’s QTH is of course much more suitably positioned than mine, being fairly high up on the Southern slope of the Magaliesburg and also checks the boxes relating to security and power.

The discussion then turned to what antennas will be used and I immediately responded that all antennas for emergency use needs to be omnidirectional and vertically orientated.

Of course I chuckled to myself as I immediately thought about the age old argument relating to which is better, vertical or horizontal.

Well in this case vertical needs to be used as most stations involved will either be mobile or some form of a field station and vertical antennas check both boxes, omnidirectional and practical.MRK also has a 6 m repeater on the Magaliesburg above the quarry next to the N1 and HAMNET also has a 10 m repeater situated on the East Rand. Both these repeaters could be very useful in an emergency situation and give by far the best overall coverage if not across the whole province, then a very large part of it. I have confirmation that the 10 m repeater is out of service at the moment with a blown power amplifier. I need to check whether the 6 m repeater is still operational.

PLB recovery

Two thirds of the way through writing this program, HAMNET Gauteng received a call to search for and retrieve a PLB going off in the Centurion area. Low and behold after checking the locations that were sent it was seen that the device was transmitting from the same informal settlement where we previously recovered a PLB. Resources were activated and the device was retrieved reasonable easily as it was in the open and by luck it was spotted in an open air market in the settlement. This time the antenna was not deployed which resulted in a greatly attenuated signal which meant that we needed to be very much closer to the location of the unit before we could hear the homing signal.

Winlink

In closing for all those Winlink enthusiasts and one of the modes that every HAMNET member should be proficient at using. There is an interesting game that is played by radio amateurs via Winlink that combines fun and a great way to test your digital emergency communication equipment without additional assistance.

Listen to Andy Morrison K9AWM from Amateur Radio

Newsline.Amateur_Radio_Newsline_20240524_HAMWord.mp3

The link that Andy referred to is https://hambooks.org/hamword/

Get your Winlink station operational and test playing Hamword.
Go to the website to get more information.

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

Focus on VHF and Above 12 May 2024

Audio version

As mentioned last week we will dig a little deeper into the Total Electron Content, what it is and how it is measured.

The Total Electron Content (TEC) is the total number of electrons present along a path between a radio transmitter and receiver. Radio waves are affected by the presence of electrons. The more electrons in the path of the radio wave, the more the radio signal will be affected. For ground to satellite communication and satellite navigation, TEC is a good parameter to monitor for possible space weather impacts.

TEC is measured in electrons per square meter. By convention, 1 TEC Unit TECU = 10^16 electrons/m². Vertical TEC values in Earth’s ionosphere can range from a few to several hundred TECU.

The TEC in the ionosphere is modified by changing solar Extreme Ultra-Violet radiation, geomagnetic storms, and the atmospheric waves that propagate up from the lower atmosphere. The TEC will therefore depend on local time, latitude, longitude, season, geomagnetic conditions, solar cycle and activity, and troposphere conditions. The propagation of radio waves is affected by the ionosphere. The velocity of radio waves changes when the signal passes through the electrons in the ionosphere. The total delay suffered by a radio wave propagating through the ionosphere depends both on the frequency of the radio wave and the TEC between the transmitter and the receiver. At some frequencies the radio waves pass through the ionosphere. At other frequencies, the waves are reflected by the ionosphere.

The impact of the the TEC on Space Weather and GPS Systems.

The use of single and dual frequency satellite radio navigation systems, like the Global Positioning System (GPS), has grown dramatically in the last decade. GPS receivers are now in nearly every cell phone and in many automobiles, trucks, and any equipment that moves and needs precision location measurements. High precision dual frequency GPS systems are used for farming, construction, exploration, surveying, snow removal and many other applications critical to a functional society. Other satellite navigation systems in orbit include the European Galileo system and the Russian GLONASS system.

There are several ways in which space weather impacts GPS function. GPS radio signals travel from the satellite to the receiver on the ground, passing through the Earth’s ionosphere. The charged plasma of the ionosphere bends the path of the GPS radio signal similar to the way a lens bends the path of light. In the absence of space weather, GPS systems compensate for the “average” or “quiet” ionosphere, using a model to calculate its effect on the accuracy of the positioning information. But when the ionosphere is disturbed by a space weather event, the models are no longer accurate and the receivers are unable to calculate an accurate position based on the satellites overhead.

In calm conditions, single frequency GPS systems can provide position information with an accuracy of a meter or less. During a severe space weather storm, these errors can increase to tens of meters or more. Dual frequency GPS systems can provide position information accurate to a few centimeters. In this case the two different GPS signals are used to better characterize the ionosphere and remove its impact on the position calculation. But when the ionosphere becomes highly disturbed, the GPS receiver cannot lock on the satellite signal and position information becomes inaccurate.

Geomagnetic storms create large disturbances in the ionosphere. The currents and energy introduced by a geomagnetic storm enhance the ionosphere and increase the total height-integrated number of ionospheric electrons, or the Total Electron Content (TEC). GPS systems cannot correctly model this dynamic enhancement and errors are introduced into the position calculations. This usually occurs at high latitudes, though major storms can produce large TEC enhancements at mid-latitudes as well.

Near the Earth’s magnetic equator there are current systems and electric fields that create instabilities in the ionosphere. The instabilities are most severe just after sunset. These smaller scale (tens of kilometers) instabilities, or bubbles, cause GPS signals to “scintillate”, much like waves on the surface of a body of water will disrupt and scatter the path of light as it passes through them. Near the equator, dual frequency GPS systems often lose their lock due to “ionospheric scintillation”. Ionospheric scintillations are not associated with any sort of space weather storm, but are simply part of the natural day-night cycle of the equatorial ionosphere.

Thanks to the Space Weather Prediction Center of the National Oceanic and Atmospheric Administration of the United States for this information.

Now onto the interesting part. I have managed to download historical TEC data from two specific reception reports on 2 May 2024.

The first one is a QSO logged between A65BR in the UAE and 3B8DU in Mauritius.

The time that the contact was logged was 16:33 UTC and I pulled the TEC images for the times 16:25, 16:30 and 16:35 UTC. Looking at the images one can clearly see that there were 2 areas of elevated TEC, one just North of Mauritius and the other one over the Persian Gulf.

The second one is a reception report of the signal of V51WW in Northern Namibia by IK7EZN in Southern Italy. Here the reception report spanned a time frame from 18:59 to 19:17 UTC with the strongest signals being between 19:09 and 19:17 UTC.

I pulled the TEC images for 19:05, 19:10 and 19:15 UTC and once can again see the elevated levels on TEC over Central and North Africa.

It must be noted that in both cases that the TEC was not at it’s highest levels denoted by the orange and red colours on the images, but in the green range which is around the 50% mark.

Zooming into the raw images one can actually see the the contour lines on the intensity of the TEC which gives a better indication of the actual levels at the time of the contacts and signal reports.

This definitely needs further studies but there is unfortunately no automated way of extracting the data and so it is a manual process that needs to take place to extract the archived TEC data and of course one needs the contact information which needs to be extracted from the reverse beacon networks like PSKreporter and of course there needs to be amateurs at either end making contacts.

Another case for specific beacons located in the most favourable TEP locations that are transmitting continuously and reception stations monitoring and logging the data to determine exactly when the favourable conditions exist and then correlating that with the data collected by the space scientists.

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

Focus on VHF and Above 5 May 2024

It has been three weeks since I last wrote a Focus on VHF program for Amateur Radio Today.

Anette ZR6D and I travelled down to Cape Town to attend the SARL AGM and Anette also visited the Archives in Cape Town to gather some more information on the history of amateur radio in South Africa. Since our visit to Cape Town we have collected even more information and we are now in the process of cataloguing everything that we have and naming the electronic files with meaningful file names to make searching and retrieval of the information in the digital archive easier.

Firstly let us catch up on what has been happening over the last three weeks.

The TEP propagation is still on going and the EU-AF 2m TEP WhatsApp group is still a hive of activity. As of yesterday evening the group had 1ay 202423 members. There are daily reports of contacts using Q65 for stations suitably located either side of the magnetic equator. The two countries in the Southern Hemisphere that are the most active are Namibia and Reunion Island.

On 23 April 2024 there was a 70 cm Q65 reception report between FR4OO on Reunion Island and A65BR in the UAE at a distance of 5158 km. Unfortunately no QSO was completed.

Lower down on 6 m there is also still regular activity being reported and contacts being made, especially using FT8.

The 8 m band is also showing some interesting contacts. On 16 April the 40 MHz beacon of Willem ZS6WAB was heard in Perth, Western Australia by a shortwave listener, Tony Mann.

Andre, ZS1F reported good openings to Europe on 21 April, the longest path being to Poland. Andre’s first FT8 contact on 8 m was with the special event station AO75MU in Spain on 40.680 MHz. On 24 April Andre’s FT8 signals on 8 mwere reported in Israel, Bonaire, Europe and the USA. It is not only Andre who is being heard in Europe, but Gilbert ZR1ADI has also been heard by Andy, EA7KBX in the south of Spain. Thanks to John EI7GL for the information on the VHF activity. You can read a lot more on John’s blogspot at ei7gl.blogspot.com.

Back to our trip to Cape Town. I was asked by our President Nico ZS6QL to give brief presentation on the Karoo beacon and the science behind it at the AGM in Cape Town. When we drive down to Cape Town we always try to avoid N1 with all the trucks on the highway. So we take the N12 via Kimberley, but this time instead of joining the N1 at Three Sisters we decided to divert at Britstown and take the route over Carnarvon, Williston, and Calvinia and join up with the N7 at Vanrhynsdorp. We spent the night in the Old Jail in Britstown, cell no 3, 25 to life, leaving early the next morning before sunrise on the road to Carnarvon. As the sun was rising the mist in the Karoo was very evident and it immediately got me thinking about the Beacon Project and the science behind tropospheric propagation and purpose of the Karoo Beacon. The relationship between temperature, humidity and pressure and temperature inversions where the cool moist air is trapped by the warmer layer of air above it. The temperature inversion layer was very evident and consistent and could be seen 360° around us. The answer to the question that I get asked quite regularly, “Why the Karoo?”, was right in front of me.

As we were driving I was imagining all the potential propagation opportunities that may be there that we do not even know about and the only way that we will ever know about them is through the Karoo Beacon Project where the beacon transmits a signal 24/7 and there are monitoring stations, commonly known as a reverse beacon network that will be listening 24/7 for the beacon and recording instantaneously when the beacon is heard, the time and the signal strength. I was also thinking about how little we actually know about tropospheric propagation and all the potential research projects that could stem out of the data that will be produced by the project over time. I compiled in my mind a long list of questions that needed to be answered about tropoducting, and I again thought about the success of the WSPR beacon network and all the research that is being done by scientists using data collected by radio amateurs.

Of course as the day progressed the mist disappeared and I just admired the unique beauty of the Karoo and how radio quiet it must be. No cellphone towers except for in the towns. Long distances without no communications of any sort. I understand why the area was selected for the SKA project.

On our return trip we again made use of the Old Jail in Britstown and on the road before sunrise, but this time there was no mist over the Karoo, just a reminder that tropospheric propagation conditions are transitory in nature and again why we need to study the conditions and try and predict when good propagation may be possible so that we can exploit the opportunities for long distance VHF and above communications more often

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

Focus on VHF and Above 10 March 2024

Audio version

There has again been good tropo predictions along the West Coast, but no reports of good contacts.

Most of us know of and have used EchoLink in the past connecting to a repeater or node and being able to chat where ever you can. We have also had an equal amount of frustration and a learning curve trying to get audio levels set correctly. Never mind the frustrations to get it working on different computer platforms. Once you master the tool then it works very well. There is a new version of EchoLink available that runs entirely in a Web browser. Go to https://www.echolink.org/faq_webapp.htm for more information and the link to the Web App. Hopefully this app will make life easier for many Echolink users.

Just two weeks ago I reported on my go-kit working like charm and so the next opportunity to use the go-kit arose last weekend with the HAMNET 40 m Simulated Emergency contest. This time I was using the FT-857D that is in the go-kit. Sunday afternoon was a sweltering day here in the north of Pretoria and I parked my vehicle in a nice sunny spot so that the solar panel on the roof could keep the battery charged. I was also using the vertical whip antenna mounted on the roof rack of the vehicle. The FT-857D front panel can disconnected from the radio and extended with a two cables, one for the front panel and the other to extend the microphone. Perfect, I’ll sit under a shady tree and operate my radio a short distance away. Nope.
I found that I did not have the RJ45 female to female connector for extending the microphone with me. I know I have two of these connectors as I purchased a second one as a spare, but I could not find either, so I ended up sitting in the sun next to the vehicle trying to make contacts. Damn it was hot as hell.

Lesson learned, check your equipment regularly to make sure that everything works in all the possible configurations that you may use it in. I need to get on the air more often to ensure that I iron out all the little issues, which may be a big issue in the event of an emergency deployment.

Last week I found a very nice PDF booklet compiled by Noël Martin F4JJD with the title “Amateur Radio Booklet”. The booklet contains a wealth of information consolidated into 87 pages that can be very useful to have on your phone or computer that you use as your station controller. It also shows the bandplans for all three regions.

You can download the booklet from https://github.com/NoelM/hambooklet

Hopefully we will have more VHF and above news next week.

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

Focus on VHF and Above 3 March 2024

Audio Version

The tropoducting along the West Coast has been phenomenal and very good long distance contacts have been made over the last couple of days.

Hepburn_Chart_South_Atlantic_1800UTC_20240301.jpeg

The ducting has extended virtually right around the coast of South Africa, however I have only seen reports of contacts coming from the West Coast.

Looking at the week ahead it seems the ducting will dissipate along the South and East Coasts, but by Thursday extending across the South Atlantic from the West Coast of Namibia to the East Coast of Brazil.

Hepburn_Chart_South_Atlantic_0000UTC20240307.png

Knife Edge diffraction

I have previously mentioned Knife Edge diffraction, the one case was testing of the new ICOM IC-905 where the knife edge effect allowed low power microwave propagation over a distance of 25 km. The second case was knife edge propagation on the 2 m and 70 cm bands in Europe allowing access to a repeater 160 km away.

I have found another article, this time in India in the hilly terrain in the Kolhapur region. The line of sight distance between the repeater and the base camp was only 10.6 km yet there was no line of sight between the two points. Only hilly terrain. The problem mainly being that the handheld radio at the base camp is only transmitting a 1 W signal. The author who goes by the pseudonym of “nuclearrambo” and is a radio ham goes through a detailed explanation of the problem and how they used the Friss transmission equation to calculate the path losses which were huge. They then went back to the proverbial drawing board, the path profile on Google Earth and started looking at the possibility of knife edge diffraction.

Nuclearrambo says “The knife edge diffraction math is a bit much to calculate manually. Therefore, I have used a tool known as RadioMobile which takes the terrain into consideration and theoretically calculates the received power at the receiver.”

Additionally, apart from the topography, RadioMobile also takes into consideration the vegetation, soil type, soil conductivity, moisture, etc. The tool itself is based on the Irregular Terrain Model (ITM) which was created for VHF and UHF terrestrial broadcast coverage analysis.

Based on the output, we can evaluate if a certain communication link is feasible or not.” The output from RadioMobile looked promising in theory. He goes on to say “Now, you would say this is all mathematics, did it actually work? I, along with other witnessing hams would agree that communication between the bauxite station and base camp did happen. The signal report logged was indeed 4/4 to 4/5 range. It was quite exciting to experience the fact that if done right, theory and practice complement each other. A mere 1W signal can reach across the mountain all because of phenomenon known as the knife edge diffraction.”

You can read the full article at https://nuclearrambo.com/wordpress/experiencing-the-significance-of-friis-transmission-equation-and-knife-edge-diffraction-at-kolhapur-medical-camp/

To see the complex calculations needed for diffraction take a look at the ITU Recommendation ITU-R P.526-14 Propagation by diffraction https://www.itu.int/dms_pubrec/itu-r/rec/p/R-REC-P.526-14-201801-I!!PDF-E.pdf

RadioMobile is a freeware online tool written by Roger Coude VE2DBE and can be found at https://www.ve2dbe.com/english1.html.

The tool can also be downloaded and installed on your computer, but requires minimum Microsoft Visual Basic Runtime (Service pack 6).

This is a very useful tool and I have used the online version many a time to calculate the expected path losses for a radio link without getting hung up in the mathematics.

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

Focus on VHF and Above 25 February 2024

Audio Version

I would like to apologise for not having a program ready for last week to be broadcast. Unfortunately time was not on my side during the week and we also had the Dis-Chem Ride for Sight cycle event taking place on the 18^th as you will have heard in the HAMNET report.

Charles ZS1CF sent me a report on a fox hunt that took place Saturday 17 February.

Charles says “The Western Cape Radio Group held their 8th fox hunt on Saturday 17 February.

We gathered at the new Nautica mall which is opposite the Laguna Mall in Langebaan. A number of guys from Cape Town came to join us, which we are very grateful for.We had a record 10 participants namely Marais, Hendrik, Fritz, Charles, Peter, Michael, Derick, John, Johan and Christo.

Christo came from Stellenbosch and is not a radio amateur. He works for a company searching for cell phone signals and interference using specialised radio detection equipment.

The fox was found first by Hendrik, using his father, Marais’, doppler system. His system has beaten the professional system from Stellenbosch, can you believe it!!!The prize for finding the fox with basic equipment was won by Fritz, using an AMSAT SA Yagi. Charles won the lucky draw prize.

After the fox Hunt we met at Die Watergat for the prize giving. Die Watergat sponsored the pizzas and we had to buy our own drinks.

It was once again a successful event and enjoyed by every one,

Thanks to Marais for making the arrangements.

Greetings from the West Coast,

de Charles ZS1CF.”

Well done to all the guys who participated in the fox hunt. It is not always about the latest and greatest piece of equipment, but the skill of the operator using the equipment that makes the difference and of course the more one practises the more one hones your skills. Fox hunting skills are an essential skill for all HAMNET operators as we have in the past year had to search for 3 Emergency Locator Terminals and 3 Personal Locator Beacons.

It is also a fun event to arrange and participate in.

Thanks for the report Charles, ZS1CF. It is always great to hear about the activities along the West Coast.

I am also pleased to see that there is more and more activity being reported on the 46 WhatsApp Group which mainly has VHF enthusiasts from Division 4, the Freestate and 6, the old Transvaal, but it is not limited to only those divisions as there are amateurs from Division 3, Northern Cape and 5 Kwazulu Natal who have also made good long distance contacts with the larger group of amateurs based in the Gauteng area. The group went silent for a while after the key of Carl ZS6CBQ went silent.

You may remember one of my projects late last year was building a go-kit that I can pretty much use anywhere. Well, the go-kit is finished, that is if a project ever can be finished because just when you think you and have thought of everything, then you think of something else that you have not considered previously. The kit has been in use since mid January and seems to be performing pretty well. Everything I have needed or needed to do so far has been achieved.

So, while stumbling along looking for some interesting VHF and above related information to write about I came across a VW Golf GTI that is also a pretty nice ham radio station as well including a short tower mounted on a roof rack on the roof of the vehicle. Go to YouTube and search for “stealthgti” and look at the videos of Scott Farrell KE4WMF about his mobile amateur radio station in his GTI.

In the days of old before the internet took over there was a VHF magazine published from 1969 to 2013. This magazine contained all sorts of articles not only about VHF, but they covered everything from the 10m band all the way to 122 GHz. There was an enormous amount of information on how to homebrew just about anything for the VHF and Above bands.

These magazines, including an index of articles sorted according to the different bands has now been captured and published on the Internet Archive at https://archive.org/details/vhf_communications

I have just done a quick scroll through the index and there is certainly a lot of interesting articles. There is also an ISO image of a DVD with all the magazines that were published as well as an index.

This digital archive, https://archive.org, has a wealth of information stored on it and it is certainly a resource that is worth bookmarking.

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

Focus on VHF and Above 11 February 2024

Audio version

Last week I spoke about radio amateurs being innovators. Listen to

Andy Morrison K9AWM in Amateur Radio Newsline Report 2413

HAMS GET CREDIT FOR ADVANCING THE INFORMATION AGE.mp3

There are two articles on the https://ieeexplore.ieee.org/ website that are worthwhile to read:

Crucible of Communications: How Amateur Radio Launched the Information Age and Brought High Tech to Life: Part 1: The Birth and Breadth of the Ham Radio Hobby.

https://ieeexplore.ieee.org/document/9928087

Crucible Of Communications: How Amateur Radio Launched The Information Age And Brought High Tech To Life Part 2: Hams Bring Real-Time Communications To The World.

https://ieeexplore.ieee.org/document/10328195

There is a new book released by Jim Wilson K5ND that will be of interest to VHF enthusiasts called “Magic Band Revealed”

Jim says “I’ve spent the last few months working on a new version of my book Capture the Magic of Six Meters. It has a new title and substantially more content. It’s titled Magic Band Revealed — Everything You Need to Know for 6 meter Amateur Radio Dxing.”

“Capture the Magic of Six Meters was downloaded over 7,000 times, from its publication in August 2020 to the introduction of version 2 in July 2022. Version 2 downloads reached nearly 1,000. This retitled version adds separate chapters on FT8/FT4, MSK144, and Q65 operation. It also has new chapters on contesting, rover operation, and awards. New appendices are provided on SDR operations and EZNEC antenna modeling. If you liked the earlier versions, you’ll want to take advantage of this one.”

You can find the free PDF version of this book on Jim’s website at https://k5nd.net/2023/11/magic-band-revealed/

Jim also has an excellent article on his website specially for new amateurs “Guide to 6 Meter DXing — Getting Started on the Magic Band”. Jim says that all it takes is

AVERAGE EQUIPMENT + LIMITED ANTENNAS = EXCEPTIONAL QSOS.

The article can be found at

https://k5nd.net/2020/11/guide-to-6-meter-dxing-getting-started-on-the-magic-band/

FOSDEM the Free and Open Source Developer’s Meeting, is a yearly conference that took place in Brussels, Belgium on 3 - 4 February 2024. This conference featured a room on Software Defined Radio and Amateur Radio. Many radio amateurs including our IARU Region 1 president Sylvain Azarian F4GKR, gave presentations at the meeting. You can access and view the presentations on the FOSDEM website at https://fosdem.org/2024/schedule/track/radio/

This is only one track of many at the FOSDEM Meeting.

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

Focus on VHF and Above 7 January 2024

Audio version

As this is the first Focus on VHF for this year I would like to wish all of you a Happy New Year and may you have lots of fun with the toys that are available to us in this fantastic technology past time that we have that is called Amateur Radio.

I have had a report sent to me by Nigel ZS6RN alerting me that the 8 m CW beacon of Willem ZS6WAB on 40.675 MHz has been heard regularly in the south of Portugal by a listener between the hours of 1100 to 1300 UTC over the past couple of days.

It does not seem that there is any other news of activity on the VHF and above bands locally.

Following on from Focus on VHF on 10 December where I gave feedback on the Science Forum that we participated in at the CSIR Convention Centre. I found a video on the blogspot of John EI7GL with the title “ From Signals to Solutions: Amateur Radio's Impact on the Future of Engineering”. The video is of a presentation recently given by the president of the Irish Radio Transmitters Society Enda Broderick EI2II to Engineers Ireland where he “explores how the modern version of Amateur Radio can impact the interest of future generations to look at Engineering differently. The hobby has all the elements associated with STEAM and can be used to develop a creative and fun environment to develop within.” STEAM stands for Science, Technology, Engineering, Arts, Maths. We have all locally heard of STEM which is Science, Technology, Engineering and Maths. Interesting that they are including Arts as well.

You find the video on https://ei7gl.blogspot.com/2023/12/video-from-signals-to-solutions-amateur.html

So how have you progressed on your to-do list of the holidays?

Have you managed to put a small dent into it, never mind having checked off all the items on the list. I guess most of the the amateurs who are still employed in a regular 9-5 job will be back in the office from tomorrow and any outstanding projects will again be relegated to the bottom drawer till next time, when ever or if ever it will be.

As mentioned last week I have made some progress on my list, but not nearly everything that I had planned. This week I managed to sort out my Go-Kit’s drawer which can now close properly and the programming cable to the FT-8800 that was giving me problems has been sorted and I can program the radio on the fly when it intermittently losses its memory. I’m using Chirp on the Raspberry Pi and it works slightly differently to Chirp on Windows. It took me a while systematically testing various combinations of programming cables and software to figure out where the kinks are.
I have also managed to get the Adafruit GPS in the Go-Kit sorted out and in a suitable protective case along with a serial to USB interface. I have also managed to play with the LoRa modules and get them operational. Still need to do some long range testing of the modules, but I need to get a play buddy amongst the HAMNET members on the East Rand to help with the long range testing.

I have however not managed to get anything done on QO-100 project.

Last week I mentioned that there are some folk who are unhappy about the VHF/UHF contests and low and behold a message popped up on one of the WhatsApp Groups and I quote the message as received:

“Hello all - on the VHF/UHF contests.

Following the passing of ZS6CBQ, the SARL Contest Committee was unable to find a sponsor person and club to sponsor the 3 VHF/UHF contests in 2025 (I guess that this is a typo and should be 2024).

It was decided that the SARL itself would sponsor the FM contest on the same days as the SARL National Field Day, with the aim of providing those not doing their shift of HF operation, with the possibility of operating on VHF/UHF. Additionally a change was brought in that there would be a single WhatsApp group that ALL scheds would be organised through to give everyone who wanted to participate an opportunity to get on air at the 'right time'.

There were 6 legs of UHF/VHF contests last year (2023) - 2 legs of each of:

- FM Contest

- SSB only

- Digital Contest - All digital modes

There were only logs received for the first FM contest leg and no logs for the other 5 VHF/UHF legs. So there is a need to re-boot VHF/UHF contest activity.

If those on this group are eager to run a trial contest/QSO party this year please feel free to contact Karel ZS6WN who is co-ordinating the work on the VHF/UHF contests (or myself) and we can find a date and promote it.

Hopefully interest rekindles and the SSB and digital VHF/UHF contest can make their appearance in 2025 again.

Johann Bezuidenhoudt ZS6JBZ.”

Both Karel and Johann’s email addresses are on the SARL callbook.

Now is the opportunity to get involved and rekindle the interest in the VHF/UHF contests and return it to what is was more than a decade ago with simple contest rules that suited everyone. When local clubs fiercely competed in the contest and put up contest stations that operated VHF and UHF throughout the night and made that elusive long distance contact at 0200 in the morning which clinched the contest for the club. How about one of the local clubs who previously regularly participated in the VHF/UHF contest stepping up to sponsor the contest going forward.

So what interesting project are you working on or are about to attempt? Have you thought about getting onto the microwave bands?

Have you made an exciting long distance 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.

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

Focus on VHF and Above 24 December 2023

Audio version

I stumbled across some information that I thought I should share regarding antennas and there was a reference to what is the best antenna to use when you do not have a metal ground plane available on for example a vehicle that has a fibreglass roof or canopy or perhaps a bus with large windows. It cannot be any quarter wave antenna because that needs a ground plane to mimic the second half of the antenna. The article mentioned a halfwave antenna, which we all know as a dipole. So what would a halfwave antenna that mimics a dipole for mounting on a vehicle with a fibreglass roof or canopy look like. The simplest way to describe the antenna is one made with coaxial cable that has 9 turns coiled at the bottom around a 25 mm former like a piece of 25 mm plastic conduit and then it extends 904 mm above the coil. The upper 457 mm of the coax cable’s braiding is stripped off. This then works like a vertical dipole.

Commercial 2 m halfwave antenna

https://www.smileyantenna.com/product-p/14680.htm

Homebrew 2 m halfwave antenna 7

2m_Halfwave_Coaxial_Dipole.jpg

But how do you mount the antenna on the vehicle. A suction lifter like the ones that you use to lift glass will work very well.

Single_Suction_Lifter.jpg

Dual_Suction_Lifter.jpg

Suction_Mounted_Antenna_on _Bus.png

On 15 December there was an unannounced HAMNET exercise and no ip based networks and no cellphones were to be used. All comms needed to be via radio. The first place we went to was to see which FM repeaters were operational and whether we could talk via the repeaters across the province. Gauteng being the smallest province should not be too much of a problem and I did manage to talk to Sasolburg via the West Rand repeater from my QTH on the north side of the Magaliesberg. This got me thinking, sending formal emergency messages via voice is tedious and prone to mistakes, but why do we not get a FM Winlink network up and running using Vara FM and some Vara FM Digipeaters or even good old packet radio that was so popular in the past. By the way there are still pockets of amateurs using packet radio very effectively for emergency communications in the rest of the world.

Then there is of course QO-100 that is a good project to get going and gives the ultimate coverage during a disaster or emergency situation. Having exchanged messages with Nigel ZS6RN these last couple of weeks has inspired me to get my QO-100 project up and running again. I actually have everything I need to get the project up and running, at least on the narrow band transponder.

There is also the LoRa devices that we have taken delivery of to start testing how they will work in an off grid scenario.

Another interesting project that I have started to follow is the M17 project. M17 is a digital radio modulation mode developed by Wojciech Kaczmarski SP5WWP. The project was started in 2019 by Wojciech Kaczmarski in Warsaw, Poland. A local amateur radio club he was a member of, was involved in digital voice communications. Kaczmarski, having experimented with TETRA and DMR, decided to create a completely non-proprietary protocol and named it after the club's street address - Mokotowska 17. As every part of the protocol was intended to be open source, Codec 2 released under the GNU GPL 2 license, has been chosen as the speech encoder.

M17 is primarily designed for voice communications on the VHF and above bands. The project received sizeable grants from the Amateur Radio Digital Communications in 2021 and 2022. The protocol has been integrated into several hardware and software projects already. In 2021, Kaczmarski also received the ARRL Technical Innovation Award for developing an open-source digital radio communication protocol, leading to further advancements in amateur radio.

More information on the project website https://m17project.org/.

So what interesting project are you working on or are about to attempt? Have you thought about getting onto the microwave bands?

Lastly I would like to wish all the listeners a peaceful festive season from both myself and Anette ZR6D.

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

Focus on VHF and Above 17 December 2023

Audio version

This week we are going to highlight some activities and items that I have found on the web over the last couple of weeks.

The first one is two articles in the November December issue of the Communicator magazine of Surrey Amateur Radio Communications in British Columbia in Canada and is available at

https://ve7sar.blogspot.com/search/label/SARC%20Communicator

In this edition there in an interesting article about a Tri-band dipole antenna for a handheld radio by Daniel Romila VE7LCG. The amateurs in Region which is the Americas have access to 220 MHz as well and hence the Tri-band dipole antenna. This article reminded me about the Rat Tail antenna that I experimented with on both 2 m and 70 cm which also was a basic vertical dipole that fitted in the place of the standard rubber duck antenna that comes standard with the radio and gave me 6 dB gain over the standard antenna. My antennas were two separate antennas for either 2m or 70 cm while the Tri-band dipole is three dipoles connected together on a piece of veroboard with an antenna connector that fits on the handheld radio.

All the guys that like to listen to AR Today on their handhelds and report in via the local repeater needs one of these antennas that will make it so much easier to put a better signal into the repeater. This can be a very nice project to play with over the holidays and does not take long to build. A tip from my experience. It would be a lot easier to tune the antennas is you had a Mini-VNA. Connect the antenna directly to the VNA and tune it for the centre of the band. When you place the antenna on your handheld and use it, i will work exceptionally well.

The second article that is a good read and should provoke some thought as to how we attract the younger generation to our exciting technological pastime. The article called “Towards a younger Demographic A call for a change of attitude” by John Schouten VE7TI. John says “Amateur radio, a hobby with a century-old history, embodies the thrill of communicating over the airwaves, the excitement of tinkering with radio technology, and the pride of serving as a lifeline in emergency situations. Yet, as time advances, the demographic landscape of amateur radio enthusiasts is shifting, and the need to attract younger members has become a paramount concern. In Canada, for instance, the average age of amateurs hovers in the mid-to-high fifties, reflecting a concerning trend.”

This sounds familiar, doesn’t it? Most definitely, the exact same trends in the rest of the world is mirrored here in South Africa as well. John goes on to discuss some ideas on how to attract the youth, and also makes the following statement “The hobby is not

attracting younger people because it is not marketed to them effectively. The current strategy of getting young people to come to “us” is not working out well. Instead, we should help them get started and get out of their way.”

This ties up with what I mentioned last week in Focus on VHF that we need to take the hobby to the public and not wait for the public to come to us. I especially like the last sentence “we should help them get started and get out of their way”. The youngsters do not need to be discouraged by us continually telling them how we did it in our youth. We need to give them space to explore and enjoy the hobby. We will not be around forever and we need the younger generation to take the hobby to new heights.

Nigel ZS6RN dropped me a message on Telegram this week with a question about activity on the 13 cm band and above. He also included a link to a YouTube video “Amateur Microwave - It's easier than you think!”This is an interesting video produced by Andrew VK3FS and really shows how relatively easy it is to get started in the microwave bands. Andrew says “Microwaves are the highest frequency radio bands in Amateur Radio. It's the final frontier for many amateur radio operators offering unique challenges with big rewards. This video was made to inspire and encourage the use of these bands. The demands on the spectrum around the world from commercial users have never been so great. If we want to keep these bands, we have to use them.”

The video can found on YouTube. Just search for VK3FS and you will find the video amongst some of the other interesting videos produced by Andrew.

https://www.youtube.com/watch?v=lWB6YvvY6bQ

I have also found reference to use it or lose it regarding the 10 GHz or 3 cm band. This is the band on which the downlink for the QO-100 satellite is. This time on the website of Steve Stroh N8GNJ https://www.zeroretries.org.

In particular in Zero Retries number 0128. Here Steve comments on a Facebook post by Bob McGwier N4HY where he mentions “the move towards giving 10.5 GHz to “GPS” like services is likely a direct threat to 10.1 GHz. The builders of receivers will want to have lousy cheap front ends and will want large buffer zones near the main band. Fight or we lose that band and we cannot lose this unbelievable resource.” There is some discussion about another potential geostationary satellite that will also use the 10 GHz band for a downlink, but will this be enough to prove significant usage of the 10 GHz band. I need to agree with the author, most likely not. Likewise for any of the other microwave bands that we have to our disposal that are not actively being used.

Ladies and Gentlemen, we need to get seriously active on the microwave bands or we will never be able to defend our allocated bands from the commercial users of the RF spectrum.

Something to think about. Take another look at the video by Andrew VK3FS to get some ideas.

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.

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

Focus on VHF and Above 10 December 2023

Audio version

We start today with some excellent news regarding the 23 cm band from the World Radio Conference 2023.

The following was posted on the global IARU web site:

The International Telecommunication Union’s World Radiocommunication Conference (WRC) began November 20 and continues through December 15, 2023 in Dubai, U.A.E, for the purpose of reviewing spectrum matters related to the International Radio Regulations. WRC’s are held every three to four years and includes the Amateur and Amateur Satellite Service allocations.

The agenda of items to be reviewed for this WRC was established at the completion of the last conference in 2019. Of primary importance to the Amateur and Amateur Satellite Services is Agenda Item 9.1 topic b to address the amateur services use of the 23cm band and the co-frequency use by several radio navigation satellite service (RNSS) systems in the 1240 – 1300 MHz band.

IARU’s work began four years ago with preparatory study in ITU‑R to address this agenda item and has finally drawn to a close. Our concerted engagement in the ITU‑R working parties, study groups and WRC preparatory meetings ensured that the amateur services were properly represented during the development of two published ITU‑R reports, M.2513 and M.2532. These were followed by an ITU‑R Recommendation, M.2164, that formed the basis for the discussions at WRC-23.

During the WRC-23 deliberations, strong positions were expressed by all the parties involved. The result is a well-supported compromise for a footnote in the Radio Regulations regarding amateur and amateur satellite service operation in the 1240 – 1300 MHz range. The footnote reminds administrations and amateurs of the need to protect the primary RNSS from interference and provides guidance to administrations to allow both services to continue to operate in this portion of the spectrum. The compromise was formally adopted by the Conference Plenary on December 8 and is not subject to further consideration during the final week of the WRC. The IARU team continues its work on other WRC issues including the development of agendas for future conferences.

IARU President Tim Ellam, VE6SH, noted “This is a very good result for the amateur services. The decision reached at WRC-23 on this agenda item makes no change to the table of allocations nor incorporates by reference M.2164 into the Radio Regulations. The addition of a footnote that provides guidance to administrations in the event of interference to the RNSS is a good regulatory outcome for amateurs and the primary users of this band.”

The WRC also agreed to suppress the Resolution 774 which closes the issue and satisfies the agenda item.

IARU President Tim Ellam, VE6SH, thanks Barry Lewis, G4SJH, for his success is leading IARU’s work on AI 9.1b. Looking on is (l‑r) Working Party 5A Chair Dale Hughes, VK1DSH, IARU Vice President Ole Garpestad, LA2RR, Tim Ellam, VE6SH, Barry Lewis, G4SJH, and IARU Secretary Joel Harrison, W5ZN

The final footnote text adopted at the 7th WRC-23 Plenary meeting states:

“5.A91B Administrations authorizing operation of the amateur and amateur-satellite services in the frequency band 1 240-1 300 MHz, or portions thereof, shall ensure that the amateur and amateur-satellite services do not cause harmful interference to radionavigation-satellite service (space-to-Earth) receivers in accordance with No. 5.29 (see the most recent version of Recommendation ITU-R M.2164). The authorizing administration, upon receipt of a report of harmful interference caused by a station of the amateur or amateur-satellite services, shall take all necessary steps to rapidly eliminate such interference. (WRC-23)”

This means that there are no restrictions on the Amateur Radio and Amateur Satellite services and that should there be any interference caused by an amateur radio station then the regulator where the interference was caused needs to address the matter.

A huge thank you to Barry Lewis G4SJH and his team who stuck tenaciously to their guns over the last four years. Job well done!

Some more positive news, this time from the Science Forum that took place at the CSIR Convention Centre this week. You have heard in the SARL news insert about the award for the stand and audience participation. I would like to share my personal experience of the Science Forum.

I have attended many trade exhibitions during my working career and for me this was the best exhibition that I have ever attended.

We were getting on average at least one visitor to the stand every 10 to 15 minutes. The visitors were of all ages and backgrounds and apart from one radio amateur from Potchefstroom attending the Science Forum there was only one other visitor who knew of a radio amateur and he stopped by to get some technical advice on how to connect a coaxial cable to a folded dipole as he wanted to extend the range of the receiver on his electric gate motor. All the other visitors had never before heard about amateur radio. To be able to interact with these visitors, old and young, and to share the greatest scientific technology-pastime in the world was absolutely fantastic. When you are able to explain the challenges of the rising RF noise floor and they also get excited about it once they realise how serious the problem could become is fantastic. When they leave the stand with a pamphlet in their hand and say that they are going to tell their brother about what they have seen or speak to their father to allow them to explore amateur radio further or cannot thank you enough for giving them a peak into the funtastic world of amateur radio or ask you for your contact details because they still have so many questions, tells me that we need to market Amateur Radio at every opportunity that comes across our path.

This should be done by every club and if there are no opportunities then one needs to create an opportunity, for example on two of the mornings while driving to the CSIR, I found a local business with a Gazebo on a vacant piece of land on a street corner displaying their business.

Why can a local club not do this as well? We need to change our outlook. We will never grow amateur radio if we wait for folk to come to us. We need to get out there and visually take amateur radio to the public. Let them see us operating along the side of the road, especially during morning or afternoon peaks. Likewise set up a station in the parking area of busy shopping centre on a Saturday morning and actively man the station and make contacts. For example, if you decide to do FT8 then have a large screen duplicating your laptop screen and have someone there to explain what is happening while the contacts are being made. Show them all the cool technological toys that we play with. Tell them how they can also participate in this funtastic technology-pastime.

Something to think about. What a great week this has been!

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

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.

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.