There have been many remarkable Trans-Equatorial Propagation (TEP) openings recently on the 144 MHz band from Namibia to Europe. This all started off when a group was established on WhatsApp where individuals in Europe and Africa exchanged messages to try and co-ordinate the tests.

The problem with evening type TEP is that the signals are often very distorted at 144 MHz and modes like FT8 often don't work. To address this issue, the group decided to try the Q65 mode which has been a huge success. They picked the frequency of 144.190 MHz to carry out these TEP tests.

The choice of frequency is important because it was just a frequency chosen to carry out TEP tests, it's NOT the official Q65 frequency.

The problem now is that as news of the TEP contacts has spread, European stations are starting to work each other on 144.190 MHz with Q65. The problem here is that they are blocking the weak TEP signals from Africa.

The organisers of the TEP tests moved the frequency to 144.192 MHz to avoid the interference from EU to EU contacts but the central message is that the area around 144.190 MHz should be left clear for only TEP contacts from Europe to Africa.

In terms of sequence, Africa always transmits first, Europe always second.

On the 9th of April 2024, 3B8FA in Mauritius made the first Trans-Equatorial Propagation (TEP) contact on the 144 MHz band from that country when he completed a contact with A65BR in the UAE. As the screen grab shows above, there was also a path to A71XX in Qatar.

This screen capture below from Oleg, A65BR shows the contact on the Q65 mode.

FR4OO on Reunion Island also had the same TEP as the previous day to A65BR, A71XX and 9K2GS.

Just to keep the report as complete as possible, there was also a path from FR5DN to Qatar...

In a follow up to my recent post about lightning scatter at 1296 MHz, Kadri TA1D got in touch to say that he saw another example at 144 MHz. He wrote a post about it on his blog in Turkish and that is linked from the bottom of this post. 

He has kindly given me permission to publish a version in English here. I'm using Google Translate for most of this post with a few corrections so a few errors may creep in.

John, EI7GL

***

Contribution of lightning to Radio Communications at 144 MHz ...by TA1D

Towards the end of summer 2021, I was operating from my summer QTH station in the North Aegean in Turkey / Turkiye. It was raining with lightning one day when I was communicating with Meteor Scatter on 144 MHz and I decided to check if the SV2JL/B beacon station in Greece on 144.450 MHz could be heard during the hours when lightning was concentrated in the middle of the Aegean Sea.

I turned my antenna to the west and started listening on 144.450 MHz. At that time, the sound of the CW beacon could be very faintly heard with some fading (QSB). Sometimes it became  unreadable and rose again, but overall, the signal level was very poor.

While I was listening, I also had the computer monitoring with the MSK144 mode and sometimes, the morse signal appeared clearly on the screen as short and long lines.

I noticed that I was also hearing the static crashes from the lightning and these can be seen on the screen shot above.

I noticed that I could hear the radio signals of SV2JL/B very faintly during each lightning strike. When the static crash was at a red level, the morse signals became loudly audible before dropping back down to a lower level.

I realised that I had witnessed an interesting physical event and it was possible due to my position and situation.

Is it of any use to radio amateurs? Yes, it can be useful. We can make use of meteor scatter with the MSK and FSK modes to make contacts using short pings and bursts. We could also make use of the short scatter signals from lightning strikes.

Thanks to lightning, we are listening and sending like meteor scatter communications. Lightning strikes at the appropriate angle between the two stations during our meteor scatter style QSOs may help us communicate.

In conclusion; This physical phenomenon that I have noticed and determined can be effective in amateur radio communication.

There may be articles written by people who witnessed similar events on different web pages, but I have not come across them yet.

Meteorite: Pieces of Stone, Soil, mineral and ice floating or orbiting in space.

TA1D Kadri K.Mehmet Başak

Links...

1) The full original article is on the TA1D website... http://ta1d.com/?p=226

The Trans-Equatorial Propagation (TEP) openings from Namibia to Europe on the 144 MHz continued on the 8th of April 2024. The reports from the PSK Reporter website are shown above.

As can be seen from the list, this was quite a good opening and the one big change was the path to SV1DH near Athens in Greece. The horizontal spread of stations at the northern end of the circuit was in the region of 800kms.

At 144 MHz, the signals need to cross the Geomagnetic Equator at nearly 90 degrees for TEP and it gets a lot more difficult the further the station gets from 90 degrees. That's why it is interesting to see SV1DH listed.

The optimal TEP path from Athens is probably down to Zimbabwe but there are no stations active there on 144 MHz.

Alex, SV1NZX reports... "V51JH heard SV1 and a smattering of other stations; ZD7GWM was cqing on 144.300 but sadly no copy from EA stations. SV1DH worked V51WW quite easily."

Felice, IZ8FFA reports working V51WW with 100W to a 12-element home made LFA Yagi on a 7m book.

On the 8th of April 2024, a little bit of amateur radio history was made with the first ever TEP contacts on the 144 MHz band in the Indian Ocean.

Over the last few decades, Trans-Equatorial Propagation (TEP) contacts on the 144 MHz (2m) band have been reported from South America to the Caribbean area, from the southern part of Africa to the Mediterranean area and from the north of Australia to Japan. This is as far as I know, a first for the Indian Ocean.

Inspired by the recent TEP contacts from Namibia to the south of Europe, other radio amateurs are trying other potential TEP paths. On the 7th of April 2024, A65BR in the UAE reported reception of the signal of FR4OO on Reunion Island... see previous post. On the 8th of April, three successful contacts were made as shown above.

The contacts are similar to other recent TEP contacts... made in the late evening, approx 5200km north-south path, equidistant from the Geomagnetic Equator and using Q65 to handle the distortion and weak signals.

The first contact was made by Oleg, A65BR around 16:30 UTC...

Oleg, A65BR writes... "Today TEP to FR on 2m was amazing. Q65 QSO with FR4OO done. Never try before, looks like we have permanent channel via TEP on 2m. Signals are huge, CW can be easy."

Oleg continues... "Today a QSO took place without any problems, the opening lasted 2.5 hours, the signal rose to -2 dB, FR4OO also worked 9K2GS and A71XX. Tomorrow 3B8FA will join their side, I hope it will grow together. It all started at 16.20 utc, (20.20 local Umm Al Quwain) and until 23 pm. It’s interesting to try at 70 cm.

Alex, SV1NZX reports... "FR4OO completes with 9K2GS, A65BR and A71XX on 2m. FR5DN hears A71XX for one period. Congratulations to all stations!!"

As Alex mentions, the signal from a second Reunion Island station (FR5DN) was also heard in Qatar (A7).

These are the spots from the DX Cluster...

Analysis... If the recent TEP openings to Europe are anything to go by, these openings in the Indian Ocean should be almost a daily occurrence for the few weeks around the equinox. This path is probably there year after year but it just takes someone at either end of the circuit to try it.

The Trans-Equatorial Propagation (TEP) openings from Namibia to Europe on the 144 MHz continued on the 7th of April 2024. The reports from the PSK Reporter website are shown above.

Interest is growing is these long distance TEP paths and more people are getting involved. In a previous post, I had details of how A65BR in the United Arab Emirates managed to hear FR4OO on Reunion Island via TEP on the 7th of April.

Also on the 7th of April, the PSK Reporter website shows that IK7EZN in Italy reported reception of V51NH, the second station in Namibia. IZ7EZN is the only station reporting this so I'd be always wary of just one station reporting as someone may have made a mistake reporting the incorrect band.

It is also reported that ZD7GWM on St Helena is trying the TEP north to Spain (EA) & Portugal (CT). Stations in South Africa (ZS) are also beaming north.

SV1NZX in Greece reports... "Lots of TEP action tonight - V51WW seen/worked in at least 7 PSK-enabled stations, more saw him, reported via group chat, A65BR heard FR4OO, ZD7GWM was CQing dir EA. Overall 2xV5, a few from ZS (various areas) and ZD7 vs over 80 EU and AS stations

V Important.  AF stations are CQing 1st and EU 2nd. We implore that 144.190 is kept free of tropo QSOs and attempts for EU->EU on 1st period. Tomorrow, 9K2GS and A65BR will be testing with FR at 1630z, V5/ZS-EU from 1800z and ZD7GWM will be cqing .300U/301cw from 1930z dir EA"

With the success of the now almost daily TEP openings on the 144 MHz band from Namibia to Europe, it has encouraged others to try similar possible TEP paths.

On the 7th of April, Olen A65BR in the United Arab Emirates reported reception of the 144 MHz signal  from FR4OO on Reunion Island. The distance is around 5,160kms.

The screen grab above from A65BR shows several decodes of the Q65 signal. As far as I know, it was a one way reception report and a two way contact did not take place.

This is as far as I know a new TEP path and hasn't been reported before. Hopefully, it might encourage others to try some tests on the 144 MHz band.

The Trans-Equatorial Propagation (TEP) openings from Namibia to Europe on the 144 MHz continued on the 6th of April 2024 and again to the same geographical area. The reports from the PSK Reporter website are shown above.

SV8ALQ in Greece reports... "Today was a very good opening between Greece and Namibia. I made contact with V51WW mode Q65b at 144.190 at 18.47. Best I heard him was -12dB"

The Trans-Equatorial Propagation (TEP) openings from Namibia to Europe on the 144 MHz continued on the 5th of April 2024 and again to the same geographical area. The reports from the PSK Reporter website are shown above.

There was an earlier report in the day at 12:32 UTC from Albania but this was almost certainly an error with someone reporting the 6m decodes as 2m.

The Trans-Equatorial Propagation (TEP) openings from Namibia to Europe on the 144 MHz continued on the 4th of April 2024 but to the same geographical area. The reports from the PSK Reporter website are shown above.

Alex, SV1NZX reports... "V51WW is currently the only station being heard from Africa but working IK7UXY, SV2DCD, SV8PEX, IT9GSF, IK7EZW and 9H1PA, amongst others. Same geography and area but slightly stronger signals tonight, initially

Interestingly, also, ZS4TX was tx-ing North too, although nothing was received and FR5DN was beaming to A6/TA/9K where stations are located. No luck as of yet but conditions are not ideal, to be fair."

From SV2DVD

In addition to the recent Trans-Equatorial Propagation (TEP) openings at 144 MHz from Namibia to Europe, there have also been similar openings from the far south of Japan to the north of Australia.

The map above shows the paths reported on the PSK Reporter website for the 3rd of April 2024.

In fact, there have been almost daily openings reported from at last the start of March. Here are a few of the spots from the DX-Cluster...

Most of the signals are FT8 with no mention of the Q65 mode. There have been a few SSB contacts as well.

The distances are in the region of 4,900kms and the southern end of the path seems to be determined by the fact that most radio amateurs in that region are clustered around the city of Darwin.

There seems to be very little activity from Japan despite the sea path to the south with possible tropo extensions. I wonder if VHF stations in Japan are aware of these TEP openings to the south?

Day 4: This was the 4th day in a row that there was a Trans-Equatorial Propagation (TEP) opening on 144 MHz from Namibia to Europe. It's very likely that this path was open for most of March as well but there was no-one testing the path.

The paths from the PSK Reporter website are shown above and this time, the signals reached further north in Italy.

Here are some spots from the DX Cluster...

Bernie, ZS4TX reports that a new 144 MHz beacon has started in South Africa to investigate the possibility of Trans-Equatorial Propagation (TEP) to the Mediterranean and Europe.

Bernie, ZS4TX writes... "New ZS Beacon for 2M TEP tests in April from KG33XU. ZS6RVC has started a 25W beacon on 2M with a 14 element yagi 20M high on a mountain site with a clear shot to EU.

Analysis... As the 144 MHz signals are likely to cross the Geomagnetic Equator at right angles (90 deg), the most likely area for reception of this beacon is probably going to be the eastern half of the Mediterranean.

Back in 1981, there was a TEP opening on 144 MHz from this part of South Africa to the Athens area in Greece so it may be possible again.

The most significant VHF amateur radio news at the moment in Europe is without doubt the TEP (Trans-Equatorial Propagation) openings on 144 MHz to Namibia. See 1st April.

Tuesday the 2nd of April 2024 was Day 3 of the recent opening and the reports on the PSK reporter site are shown above. The paths are similar to the previous two days except the path to SV2DCD is a new one.

The screen grab below is from SV2DCD which shows reception of V51WW. As far as I know, a two way contact was not completed.

What made this day special though was that some contacts were made on SSB! Tom, SV8PEX posted this on the DX Cluster... SV8PEX 144150 V51WW 18:33 02 Apr 24 JH81 SSB 52 52 many thanks!!!

Alex, SV1NZX reports that V51WW made four SSB contacts on 144.150 MHz with IK7UXW, IK7JNM, IK7LMX and SV8PEX.

As outlined in this previous post, there was a TEP (Trans-Equatorial Propagation) opening on the 144 MHz band between Namibia and Greece on the 31st of March 2024. As news spread that SV8PEX had been heard over 6500kms away in Namibia, more stations were active on the evening of the 1st of April.

This time, there were paths from Namibia to Greece, Italy and Malta and SV8PEX, 9H1TA and 9H1PA managed to complete contacts.

Alex, SV1NZX reports the following... "Tonight ends an exciting night for 2m #TEP QSOs - V51WW worked 9H1PA, 9H1TX and SV8PEX as well as receiving 4-5 other Italian stations in JN70, JN80. SFI measured at 125, K/A index at 5-8 and 1, all QSOs in Q65b, 30/60s."

This is a screen grab from SV8PEX in Greece...

This screen grab below is from V51WW and shows some of the exchanges with IK7UXW and IZ8EDJ  in Italy.

The screen grab below is from David, 9H1TX in Malta...

9H1TX writes... "Just finished my first TEP 2M qso with V51WW. I am totally closed to south but i elevated the system at 8 deg and was lucky to get his signal."

Analysis... As the map shows above, both stations are about equidistant from the Geomagnetic Equator and are crossing it at right angles, an important consideration for TEP signals at 144 MHz.

V51WW in Namibia is using 100w into a horizontal 9-element yagi 12m above ground level which is a pretty modest station. It shows that this TEP path to Europe is probably there a lot more often than people realise but the problem is that there weren't any stations in Africa to attempt a contact.

It would be interesting to see how far east and west in the Mediterranean the signal from V51WW can reach? How far from the 90 degree right angle at the Geomagnetic Equator can the 144 MHz signal go before it becomes impossible? EA6? IS0? 5B4? TA? SV5? SV9?

The Mediterranean is also an excellent location for tropo ducting. How far will that carry the signal north?

Are there any other stations at the southern end of the TEP zone? ZD7 (St Helena) to Spain seems an obvious one. Other paths?

It would be good to see more TEP reports from Europe to Africa on 70 MHz, 88-108 MHz and 144 MHz.

Links...

1) See my 144 MHz page for plenty of reports of other TEP contacts.

Over the last few years, there have been many reports of contacts on 144 MHz from South America to the Caribbean region via Trans-Equatorial Propagation (TEP). There have been no reports of similar openings on 144 MHz from Europe to Africa in the same time period.

On the 31st of March 2024, it looks as if finally there was a TEP opening when V51WW in Namibia managed to receive SV8PEX in Greece, a distance of about 6532kms.

This is the report from the PSK Reporter website...

Tom, SV8PEX reports... "Unfortunately I was too late sig went down, one way. I was using 500W and V51WW I guess 100. Me -15db the best". Tom also notes that they tried FT8 and no decodes were possible.

Alex, SV1NZX writes... "First confirmed TEP reception of a signal between EU and AF tonight by V51WW from SV8PEX on 2m band after almost 40 years since the last signals between AF and EU intersected. Mode Q65a/30s "

Analysis... As the map shows above, both stations are about equidistant from the Geomagnetic Equator and are crossing it at right angles, an important consideration for TEP signals at 144 MHz.

As SV1NZX mentions, there used to TEP contacts on 144 MHz from Europe to Africa back in the 1970's when there was activity from Zimbabwe. The key thing is the location. Zimbabwe and the north of Namibia are far enough north for signals to reach the TEP zone. There are plenty of stations in South Africa (ZS) active on 144 MHz but they are much further south.

In this particular case on the 31st of March, it was a reception report but it shows that a TEP path was open at 144 MHz. Hopefully more stations in southern Europe will now beam south and see if the path is open to Namibia and the southern part of Africa. 

It would be good to see more TEP reports from Europe to Africa on 70 MHz, 88-108 MHz and 144 MHz.

Links...

1) See my 144 MHz page for plenty of reports of other TEP contacts.

By the way, this is not an April Fools Joke! I know I posted it on the 1st of April so some might be wondering.

I was recently looking at the website of Bert Modderman, PE1RKI in the Netherlands and I noticed that he is selling cavity filters for the 144 MHz band.

A cavity filter is essentially a hollow tube with tuning rods inside and can usually handle much higher powers than say a lot of the smaller band pass filters on the market which use inductors and capacitors.

The specs for this filter are that it has a 0.2dB insertion loss and it can handle up to 1-kilowatt of RF. It comes supplied with N-type connectors.

I have edited the diagram of the frequency response for the filter to make it clearer.

Signals on the marine band around 156 MHz are down about 18dB. Signals in the VHF air band (~120-130 MHz) are down about 10 - 12 dB.

If we were to extrapolate the shape of the graph down to say FM broadcast band on 88 to 108 MHz then the signals are probably down about 15 - 20 dB.

PE1RKI also makes a version for the 432 MHz band.

More information about the filters can be found HERE

Disclaimer: Just to be clear, this isn't an advertisement. I wasn't paid for this post or I wasn't sent the product for review. I just think this is something VHF operators will be interested in.

PE1RKI also sells a number of amplifiers, filters and antennas for the microwave bands. We all know you can buy lots of gear from websites the likes of Ali Express and eBay but a lot of it is rubbish. It's worth considering supporting small manufacturers and shops in Europe.