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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 17 November 2024
This week, I want to take a look at TEP with reference to a post on the website of John EI7GL, https://ei7gl.blogspot.com/ about the TEP contacts between Garry, ZD7GWM, on St Helena Island and Spain and Portugal who are directly perpendicular and equidistant from the Geomagnetic Equator.
John highlights the following which is important:
In the month of October there were 22 out of 31 days where TEP contacts were reported. So it is fairly consistent as long as there are operators trying to make contact on both sides. There were some days when Geomagnetic disturbances prevented TEP from taking place.
Initial contacts were made with FT4 before moving on to a more suitable mode for TEP propagation like Q65B The physical path seems to be pretty narrow and also has a specific distance.
The times are also within the typical times for evening TEP between 19:00 and 22:00 UTC.
The equipment used by Garry is modest, 50 W power out and into a vertical Diamond X700H antenna.
Thinking aloud and looking at the TEP conditions between the South Indian Ocean Islands and the Middle East and then between Namibia and Southern Europe, we also see some similarities.
The similarities are that all of the contacts were evening TEP with the time windows shifting as the grey line was shifting.
All were perpendicular across the Geomagnetic Equator. All were equidistant from the Geomagnetic Equator and in Nambia, V51WW, the only active station is also a modest station. In the East the stations were using a lot more power, but there are fewer stations listening for them.
Looking at some of the differences between the three TEP paths that were explored are that the TEP path to the East was largely over the Indian Ocean. The central path was over the land mass of Africa and the Western path was for a large part over the Bulge of Africa.
The other difference was that of the three paths, two were using horizontal YAGI antennas and the third was a vertical co-linear antenna with possibly similar gain to the YAGI antennas.
What stands out for me is the fact that in all three cases, there were amateurs willing to experiment and be on the air.
The number of contacts were proportional to the number of operators participating and the length of time that they were on the air and most importantly the number of amateurs located in the sweet spots perpendicularly equidistant across the Geomagnetic Equator.
Everything else like the size of the station i.e. power output, type and orientation of the antenna and whether the contacts were made over land or sea or a combination there of does not seem to matter. Not even the mode used.
Just to mention something on the modes.
There has been a lot of experimenting happening and over time certain modes have been derived that better suit the type of propagation. Every propagation mode has some unique characteristics and over time it has been determined that different variations of the tones and the spacing of the tones, which also determines the bandwidth that is being used, are better for certain modes and frequencies.
Likewise once the Karoo beacon goes live we will have a combination of antennas on the beacon and the beacon will initially be using the PI4 mode, but over time we may discover that a different mode is more suited to the various modes of propagation over the interior of South Africa. Here in also lies the reason for the choice of using the RFzero for the beacon exciter. The RFzero can be reconfigured remotely on the fly to different modes. We are planning to continue with the Beacon project again in June 2025 after the Centenary celebrations of the SARL. Unfortunately there are limited resources on the project and they do not only put beacons on the air. They are also active and contribute in other aspects of the hobby.
To end this week here is a really feel good story of a teenager from Portland in the state of Oregon in the US who at the age of 8 asked his dad what it would take to talk with an astronaut. Neither of them had the answer, so they set out to find one. You can read all about Zeke Wheeler who is now 13 and his quest, supported by his father.
Be sure to watch the video as well.
https://www.kgw.com/article/tech/nasa-astronaut-iss-portland-teen-ham-radio/283-bc6ebdef-246b-4c16-b62c-b575179e7f10
I am aware of a youngster from Bloemfontein Rulhof, ZS4RM, whom I met at the AGM in Cape Town earlier this year who is also supported by his father and he is going places, there is no doubt about that.
Over the last couple of months, I have become more and more aware of youngsters who are really keen to take up the hobby and we really should go out of our way to encourage them and to get them started in this fantastic technical past time. One of their greatest challenges is how to get started. This is where all our clubs need to step up and be ready to guide these youngsters into the hobby. These are not only the hams of tomorrow, but they may very well also be our future scientists. Which clubs are able to take young budding amateurs into their ranks and guide them towards obtaining their Amateur Radio Operator Certificates? A lot of the youngsters are keen to take on the Class A licence as well. Write to us at VHF News and let me know which clubs can step in and assist so that I know where to send the young folk when they make enquiries.
Next week, I will be giving first hand feedback on the BACAR 12 event that took place in Secunda this past Saturday. HAMNET members will again be responsible for retrieving the three balloons that need to be recovered and one will not have a GPS attached to it, only a transmitter sending out a homing signal, but that will be a story for next week.
How about telling us about that exciting long distance contact that you have made on the VHF and above bands or about that project that you are working on in the VHF and above bands? Send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za.
Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.
Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ.
Focus on VHF and Above 27 October 2024
I received an email from Naz ZS1NAZ about communications with St Helena that happened late on Friday evening.
Naz says “Last night on 25 October 2024 at around 6 p.m. I beamed grid JF96GC towards St Helena Island to listen to Garry’s ZD7GWM beacon on 144.475 MHz CW, AND THERE IT WAS. This was Déjà vu all over again. I gave a few calls on 144.300 MHz USB as we had a net running and informed the VHF group to listen out for Garry and also call. Nothing heard and Garry ZD7GWM who is part of this group sent word that he is out for the evening. Despair because it would have been nice to hear others in Cape Town South Africa work Garry.
Kobus ZS3JPY also reported that he heard the beacon in Kleinzee about 600 km from Cape Town.
The night continued and most left the group but just after midnight Garry’s voice broke the silence of 144.300 MHz SSB and Déjà vu we chatted for 2 hours and hoping others would re-join and work him.
Ean, ZS1PR and Eldred ZS1DJ reported that they faintly heard the beacon but most are using collinear verticals.”
I had a long chat to Naz on Saturday and I asked about the height and elevation of the Yagi antenna and how that affects getting into the duct. Here is Naz’s reply and he provides a lot of valuable information that all VHF enthusiasts should take note of.
Finally Naz says “Never give up guys”
Naz, thanks for your report and I totally agree with you, never give up. You never know when conditions will be just right for that amazing contact.
How about telling us about that exciting long distance contact that you have made on the VHF and above bands or about that project that you are working on in the VHF and above bands? Send me a consolidated report of your activity or project with any additional photos, audio or video clips to vhfnews@sarl.org.za.
Remember by sharing your activities with us at VHF News allows us to tell the rest of the amateur community about your achievements and the more we promote the activity on the VHF and above bands the better chance we have of encouraging more amateurs to explore the world above 30 MHz.
Focus on VHF and above is compiled, edited and presented for Amateur Radio Today by Brian Jacobs ZS6YZ.Focus on VHF and Above 21 July 2024
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
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.
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 16 June 2024
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.
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.
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.