Thanks to Dragan, 9A6W for sending on this YU7EF design for a 4-element Yagi antenna for the new 40 MHz (8-metre) band.
The design with dimensions is shown below.
The calculated gain in free space is about 6.2dBd and has a front to back ratio in excess of 20dB.
Recently on the blog, I had several posts about some remarkable Trans-Equatorial Propagation (TEP) contacts made on 144 MHz between stations in the Caribbean and South America. Most of these were in the region of 5000 to 6000 kms. See my 144 MHz page for a list of posts.
Gabriel, LU1DL in Buenos Aires has kindly sent on some information about his 144 MHz TEP contacts during the months of November & December 2020 and it's interesting to see what can be worked from someone on the southern end of the TEP path.
You'll notice that all of the TEP contacts that LU1DL made were at right angles to the Geomagnetic Equator.
Here is the log from Gabriel...
With Trans-Equatorial Propagation (TEP), zones of high ionization occur either side of the geomagnetic equator in the F layer of the ionosphere. What makes the mode so interesting is that it can allow propagation on the VHF bands from 50 MHz to 144 MHz. As the zones of ionization is roughly 400kms above ground level, the propagation paths achieved are in the region of 4000 to 5000 kms, much greater than what might be usual with Sporadic-E.
Equipment... For these 5000-6000km contacts on 144 MHz, LU1DL was running 180 watts into a single 10-element Yagi with a 5m boom.
This is the antenna system for P41E in Aruba...
HI8DL in the Dominican Republic...
Video... Have a listen to this TEP contact on 144 MHz and note the distortion on the audio...
 |
| Astronaut Shannon Walker |
Students from a secondary school in the midlands are hooking up with an astronaut on the International Space Station this afternoon to try and find out how space travel is affecting life on earth. https://t.co/ljwoI4jaOW pic.twitter.com/T3wTcRTdEi
— RTÉ News (@rtenews) December 7, 2020
Preparation for our live space call on Monday starts at 1:30 pm with great music, guest speakers and more, before the direct contact is made at 2:50 pm 🚀☄️ https://t.co/yy6T8TOlEB pic.twitter.com/aMQaDVsnfh
— Athlone Community College (@ccathlone) December 4, 2020
In a message by email, Dragan, 9A6W writes...
In April I have applied for an experimental license to transmit on 40 MHz hoping to be QRV for the E-sporadic season. To make a long story short, national telecom authorities have just issued me an experimental license for 8 m band, 40,66-40,70 MHz. I am QRV with FT-897 (100 W) and a dipole antenna at the moment.
The license is valid for a year and then it could be renewed. There are rumors that some other stations will follow my example.
* * *
Croatia is now the fifth country in which it is possible to operate legally on 40 MHz. Ireland, Slovenia & South Africa already have allocations on the band while Lithuania is willing to allocate spot frequencies for experimental purposes.
The frequency allocation that 9A6W has obtained is from 40.660 MHz to 40.700 MHz. This 40 kHz wide slice of spectrum is referred to the Industrial, Scientific & Medical (ISM) band.
There are a number of ISM bands but this is the one nearest to 40 MHz. In many countries, much of the low band VHF spectrum is allocated to military or other services. Licensing authorities may be unwilling to grant radio amateurs an allocation that hasn't been agreed internationally.
The ISM band at 40 MHz is an exception and it might be a good way for other countries to proceed i.e. individual licenses in the ISM band.
Range... As the map shows above, 9A6W is at an ideal distance for Sporadic-E openings to Ireland and Lithuania. As the most southerly 8-metre station in Europe, there is a possibility of some TEP openings to South Africa or perhaps via F2 near the peak of sunspot cycle 25.
The distance to Slovenia is about 200 kms which might be spanned by tropo or even meteor scatter during the major showers.
The map above shows the FT8 signals that I heard on 28 MHz on Tuesday the 1st of December 2020. As well as evidence of some Sporadic-E signals from around western Europe, there were plenty of F2 signals from southern Russia, SE Europe, South Africa, South America, the Caribbean and the USA.
The one unusual signal of note for me was BV6CC in Taiwan. I have heard Thailand, Indonesia and Australia on 28 MHz over the last few days but Taiwan is the most northerly of the 'eastern' F2 signals that I have heard for this new cycle.
We still have some way to go yet before we start hearing Japan and California on 28 MHz here in NW Europe.
The solar flux on the 1st of December 2020 was at 104, a big change from 12-months ago when it was down around the 70 mark at the bottom of the sunspot cycle.
Hot on the heels of the last post about the 5400km TEP opening on 144 MHz between Argentina and the island of Aruba, we have details of some more contacts that reached in excess of 6000kms!
In a message, David HI8DL reports... Last night (Nov 29th 2020), Edgar, HI8PLE and I (HI8DL - FK58AL), contacted LU2EPO on 144.300 MHz at 23:57 UTC.
The mode was SSB and the distance was 6102kms.
On Nov 26th at 00:57 UTC, I (HI8DL) made a QSO with LW2DAF on 144.174 MHz. The mode on that occasion was FT8 and the distance was 6011kms.
Otra excelente noche de TEP en 144MHz, record de distancia personal 6020Km, trabajado con @HI8DL, en FT8, gracias David!!! pic.twitter.com/AUkvjFptjf
— Diego Alejandro Feil (@LW2DAF) November 26, 2020
In the map above, the geomagnetic equator is shown in Purple. Both the HI8 and the LU stations are at right angles to it which is important at 144 MHz.
With Trans-Equatorial Propagation (TEP), zones of high ionization occur either side of the geomagnetic equator in the F layer of the ionosphere. What makes the mode so interesting is that it can allow propagation on the VHF bands from 50 MHz to 144 MHz. As the zones of ionization is roughly 400kms above ground level, the propagation paths achieved are in the region of 4000 to 5000 kms, much greater than what might be usual with Sporadic-E.
Normally on 144 MHz, both the northern and southern stations are equidistant from the geomagnetic equator. The stations in the Dominican Republic seem to be slightly further away on this occasion so it's possible that there was a slight tropo extension of a few hundred kms across the Caribbean.
A 6000km contact on 144 MHz is really incredible. To put that into perspective, that is twice the distance across the North Atlantic between Ireland and Newfoundland!
In two recent posts, I covered some recent 144 MHz TEP openings from Guadeloupe to Brazil during October 2020 and from Curacao to Argentina in early November.
P41E on the island of Aruba has been also been busy during the month of November 2020 and has worked several stations in Argentina via TEP.
One of the longest contacts was with LU2EPO with a claimed distance of an impressive 5449 kms.
In the graphic above, the geomagnetic equator is shown in Purple. Both P41E and the LU stations are equidistant from it and are also at right angles to it, both factors which are important at 144 MHz.
With Trans-Equatorial Propagation (TEP), zones of high ionization occur either side of the geomagnetic equator in the F layer of the ionosphere. What makes the mode so interesting is that it can allow propagation on the VHF bands from 50 MHz to 144 MHz. As the zones of ionization is roughly 400kms above ground level, the propagation paths achieved are in the region of 4000 to 5000 kms, much greater than what might be usual with Sporadic-E.
Here are a selection of videos showing the contacts made during the month of November 2020...
Contact with LU4FW on SSB...
— P41E (@Etiennechat1) November 26, 2020
Contact with LU3FCI and great to see the vintage Yaesu FT-480R in action! ...
And of course we did some FM again. pic.twitter.com/eDlcLfiLR4
— P41E (@Etiennechat1) November 26, 2020
Contact with LU3FCI...
— P41E (@Etiennechat1) November 26, 2020
P41E was using 100 watts into a 13-element Cushcraft Yagi.
* * *
Addendum: Thanks to Etienne, P41E for sending on the following information.
This is a photo of the antennas used for 144 MHz and 50 MHz
P41E is using an old an old Yaesu FT-767GX and a Tokyo HL160V running about 100 watts.
Etienne has very kindly sent on a log extract of what he has worked on 144 MHz from the 17th to the 28th of November 2020.
There are a total of 33 contacts in total. Looking through them, some are repeat contacts on different days or on a second mode. The log contains 17 separate stations from Argentina and most of these would have been in the 4500km plus range.
You will note that the majority of the contacts are on SSB with a few on FM and FT8.
Note also the times of the contacts which are around 00:00 to 02:00 UTC. This is around 21:00 to 23:00 for stations in Argentina and 20:00 to 22:00 for P41E in Aruba. This ties in well with Trans-Equatorial Propagation which is thought to peak at about 20:00 local time.
Solar Data... Just for reference purposes, I have included the solar data for the range of dates concerned...
After a long solar minimum slumber, the sun has really begun to wake up in the last few weeks. On the 24th of November 2020, the solar flux hit 100 for the first time in about three years. The last time the solar flux was over 100 was back on the 10th of September 2017.
The photo above shows some of the sunspots on the solar disk including region 2786 which has a dark core which is slight larger than planet Earth.
The chart below shows the dramatic change in the solar flux in the last 12-months...
The biggest change in the conditions on the HF bands is that the higher bands like 10-metres are now opening. At the end of 2019 at the sunspot minimum, there were some hints of propagation but mostly on north-south paths. Fast forward to the 26th of November 2020, you can see that there was a nice opening to the USA on the 28 MHz band.
It's been a long time since I heard signals from Texas on 28 MHz via F2 propagation.
At the virtual Radio Amateurs of Canada conference last September, teacher Kelly Shulman, VE3KLX gave an interesting presentation about launching amateur radio payloads on high altitude balloons.
As the video below highlights, high altitude balloons and scientific experiments can make amateur radio relevant to a younger generation. In terms of cost and technical ability, many schools might aspire to doing their own high altitude balloon experiments where as a cubesat / satellite would be out of the question.
The 64-minute video is shown below...
There is some interference and dropouts in the presentation during the first 28-minutes but the second half is much better.
This video gives an interesting perspective of what DXing on 6m looks like from a Canadian perspective and it should be of interest to anyone thinking of getting going on the 50 MHz band.
Ofcom is the licensing authority for the radio spectrum in the UK and in a response to an informal query, they indicated to the Royal Society of Great Britain (RSGB) that an allocation at 40 MHz for radio amateurs in the near future was unlikely.
In an editorial comment in the VHF/UHF column of the November 2020 issue of RadCom from the RSGB, the VHF Manager John Regnault, G4SWX wrote... "In recent years, the RSGB has informally asked Ofcom about amateur access to 40 MHz. Ofcom responded that this was not amateur radio spectrum, whilst they would agree to the continuation of the GB3RAL propagation beacon on 40 MHz, they would not agree to further beacons or general access to 40 MHz by UK amateurs."
"Readers should also note that NoV access to unused spectrum at 71 and 146MHz was granted for innovative experimentation and not more of the same (CW/SSB/FM)."
"The view expressed by Ofcom is that UK radio amateurs have adequate VHF/UHF spectrum for these traditional activities."
The GB3RAL 40MHz beacon first went on air back in 2007 and it was only operational for a short period. The RSGB are now looking to find a new home for this 8-metre beacon and getting it operational again.
As of November 2020, just Ireland, Slovenia, Lithuania and South Africa have some sort of access to the 40MHz band.
The map below shows the FT8 signals heard on 28 MHz on Friday the 20th of November 2020.
There was evidence of some Sporadic-E to central Europe as well as F2 signals out around the 3000km mark from Greece to Russia. Even a lone signal from the west of Australia made it through.
The signals that were of real interest to me however were the ones from the south-east of the USA. This is a classic example for me of a F2 layer opening on 28 MHz. A lone VO station appeared from the 1-hop zone near Newfoundland (~3000kms) and there was a group of stations clustered around the 2-hop zone near Florida (~6000kms).
During the sunspot minimum, F2 propagation via north-south paths on the 10-metre band are always possible. As we climb out of the minimum then we should expect to see more east-west openings on the band.
From my vantage point here in Ireland, the Great-Circle path to Florida is the most southerly of the east-west openings to the USA and it would be the first area I would expect to hear with a F2 layer opening on 10-metres.
The solar-flux on the 20th of November 2020 was around the 80 mark as opposed to say 67 around the time of sunspot minimum. We still have some way to go before we get F2 openings from NW Europe to say Japan or California on 28 MHz but at least we're on the way up.
I'd suspect that the conditions on 28 MHz in 12-months time in November 2021 should be dramatically better than now. Onwards and upwards!
In this months RADCOM magazine from the Radio Society of Great Britain (RSGB), there was an interesting news article about a new propagation study on the 10-metre amateur radio band.
The RSGB Propagation Studies Committee are interested in looking at the modes of propagation responsible for signals in the 150km to 800km range.
For example, the map below shows some of the FT8 signals I heard on the 28 MHz band on the 17th of November 2020.
The signals from the Netherlands, Germany and Denmark (1000 kms plus) are easily explained as they were via Sporadic-E propagation. As the skip distance gets shorter however, it gets harder for the signal to return from the Sporadic-E layer.
Tropospheric propagation also happens at 28 MHz but it's a lot weaker than on the higher VHF bands. On the map above, the two stations about 100kms to the north of me and the station on the west coast of Wales who was about 200kms distant are probably via tropo.
The question then arises as to what is the propagation mode for the signals from England and Scotland in the 400km to 700km range? On the day, it seemed to be too close for Sporadic-E and too far for tropo.
This wasn't unique to just this particular day. It happens pretty much most of the time. Over the Summer months for example, I seem to hear G0OYQ near Hull (579 kms) on FT8 on 28 MHz practically every day.
Are these signals due to meteor scatter? Sp-E backscatter? Aircraft scatter? Tropo? The RSGB study hopes to address this.
The news article from RadCom is shown below...
* * * * *
RSGB's Propagation Studies Committee (PSC) has launched a new study to look at the mechanism behind long-distance inter-UK 10m propagation.
The study came about after PSC chairman Steve Nichols, G0KYA noticed that he was often seeing inter-UK 10m contacts on FT8 occurring between stations that were more than 100 miles apart.
"Normally you would expect 10 metres to give contacts out to about 30-50 miles at best," Steve said, "But these contacts, which are often fleeting, were over distances of about 150 miles. I also that they often appeared in the early mornings, but disappeared as the day progressed. We've had to wait for the Sporadic-E season to end to exclude Es as a possible propagation mode."
Steve said that the likely propagation mode was tropospheric, although aircraft scatter or ionospheric scattering can't be ruled out. Either way, it warrants closer examination.
To take part in the study, just log any UK stations heard via FT8 on 10 metres in excess of 100 miles, making a note of date, time, received SNR and the location of both you and the distant station. Please also include details of your antenna and any beam heading if applicable. Steve can then compare this with weather patterns and barometric information at the time.
PSKReporter.info and DXMaps.com can also be used to track contacts online. "We'd like to encourage new amateurs to take part as the reporting isn't too onerous, but the information you supply could be invaluable," Steve said. Steve can be contacted via email to psc DOT chairman AT rsgb DOT org DOT uk
Source: RadCom Nov 2020 Page 7
As can be seen from the map above, there was a pretty good opening on 28 MHz on Saturday the 14th of November 2020. Even though I have heard the north and west of Australia earlier this week, what really stood out on the 14th was the opening to the south-east of Australia. That is the furthest part of the continent away from me and the signals have to travel roughly 17,500 kms.
In total, I heard seven Australian stations on FT8 on 28 MHz...
I'd be pretty confident that these were via F2 propagation as the distance to the west to Newfoundland is about the same as the other F2 signals from the east.
The solar flux on the 14th of November was 82 which is slowly reducing having reached a recent peak of 94 on the 6th of November.
The conditions on 28 MHz on Friday the 13th of November 2020 weren't great but the band did open up to the USA.
There were some Sporadic-E signals from the centre of Europe but not a huge number. There were no Russian stations to the east heard on the band indicating a lack of F2 propagation in that direction.
And yet, a handful of stations from the USA were heard. Was it via multi-hop Sporadic-E? Was it via F2 layer propagation? I suspect it may have been F2 but it's impossible to tell.
The solar flux was around 85 which is certainly up on the last few months but is still pretty low in terms of allowing east-west paths on 10-metres.
As part of their ongoing presentation series online, the Mid Ulster Amateur Radio Club recently had an interesting talk on Amateur Radio Satellites.
The talk which is given by Dave, G4DPZ is shown below. The Q&A session starts at 1:08:10.
The video gives a good introduction to the world of amateur radio satellites and should be of interest to any beginners.
On the 16th of October 2020, there was a remarkable 3000+ km contact made on the 70cms band between South Africa and St.Helena in the South Atlantic.
The contact at 433 MHz was made between Garry, ZD7GWM on St.Helena Island and Tom, ZS1TA in South Africa. The distance was approximately 3136 kms and what was even more amazing was that the contact was made on FM!
The power used for the contact was a modest 35 watts into a vertical antenna. This was a new distance record for a contact between South Africa and St.Helena on the 70cms band.
The mode of propagation was probably a marine duct as shown by this tropo forecast map from Pascal, F5LEN.
This 3000km+ tropo path between South Africa and St.Helena opens up on a reasonably regular basis. Back in November of 2018, there was an opening on 144 MHz as outlined in this previous post.
In June of 2020, the 2m path opened up again and the most recent opening on 2-metres was on the 23rd of September 2020 when ZD7GWM was worked by no fewer than five ZS stations... ZS1TA, ZS3CVB, ZS1CF, ZS3JPY and ZS1FC.
To put these remarkable contacts on 144 MHz and 433 MHz into context, the 3136 km distance is equivalent to the path across the North Atlantic between Newfoundland and Ireland.
Both 6M and 10m were open between Slovenia and Ireland, and so it worked on 8m as well.
Tim was quite strong with me, but unfortunately I only had my G5RV antenna available, with a tuner.
Distance covered: 1730 kms (JN75PX to IO63WE) Signals were TX:+5 RX:-20. Time was 13:40z on 31Oct 2020"
40 MHz allocations... At the time of writing of this post (Nov 2020), a total of four countries have some sort of access to the 40 MHz band... Ireland (EI), Slovenia (S5), Lithuania (LY) and South Africa (ZS).
Most of the activity is centered around 40.680 MHz which is in the middle of the ISM (Industrial, Scientific, Medical) band which goes from 40.660 MHz to 40.700 MHz.
More information about the 40 MHz band can be found on my 40 MHz page... https://ei7gl.blogspot.com/p/40-mhz.html
After reading reports of recent activity on 28 MHz, I started listening again on FT8 on the 10-metre band to see what conditions were like.
As the PSK Reporter map above shows, there was plenty of activity on the band on Friday the 6th of November 2020.
While there was some evidence of Sporadic-E activity around Western Europe, there was plenty of evidence of F2 propagation from Russia and SE Europe. Outside of some North-South propagation to Africa and South America, it was interesting to see openings to Indonesia and Australia.
There's always something special for me about hearing Australia on 28 MHz. It's no big deal on the other HF bands but for the path to be open at 28 MHz then something must be happening.
As we come out of the sunspot minimum, there will be peaks and dips but the overall projection is still upwards. As the solar flux increases, the higher HF bands will spring into life especially on North-South paths.
It will be interesting to see when will we get regular openings to the USA on 28 MHz from NW Europe? It will probably start with openings to Florida but it's the F2 openings to Newfoundland, Nova Scotia and Maine that I'd be really interested to see.
In a recent post, I reported on a Trans-Equatorial Propagation (TEP) contact between Guadeloupe and the south of Brazil on 144 MHz which happened in October of 2020. The distance for that contact was in the region of 4455 kms.
At the start of November 2020, there was an even more remarkable 5312 km contact between PJ2BR in Curacao and LW2DAF in Buenos Aires, Argentina.
With Trans-Equatorial Propagation (TEP), zones of high ionization occur either side of the geomagnetic equator in the F layer of the ionosphere. What makes the mode so interesting is that it can allow propagation on the VHF bands from 50 MHz to 144 MHz. As the zones of ionization is roughly 400kms above ground level, the propagation paths achieved are in the region of 4000 to 5000 kms, much greater than what might be usual with Sporadic-E.
What's even more remarkable about this contact is that it took place on SSB! See the video below...
QSO de anoche en 144 MHz vía TEP con @PJ2BR, 5300 Km. GF05<>FK52. pic.twitter.com/e8EXOPCLDz
— Diego Alejandro Feil (@LW2DAF) November 3, 2020
If you listen carefully, you can hear a warble on the audio as the SSB signal becomes distorted on the 5300 km path.
PJ2BR worked a number of other stations in Argentina on 144 MHz SSB as well including LU2EPO at 5367 kms. Other stations worked were LU7DW, LU5BE, LU1DL and LU4DIR.
The opening was on the 3rd of November 2020 at around 00:00 UTC which was at 20:00 local time on the 2nd of November for PJ2BR in Curacao.
To put the 5300km distance in perspective, it is the same as the distance between London in the UK and the city of Boston in the USA.
