Tuesday, June 30, 2020
RSGB Video: Antennas for small gardens with Steve Nichols, G0KYA
The RSGB have recently put a video up on YouTube entitled "Antennas for small gardens with Steve Nichols, G0KYA"
Most radio amateurs have modest or small gardens and those on HF will have an interest in getting the best antenna working in a limited space.
In this video which is 80 minutes long, Steve G0KYA presents plenty of options for radio amateurs to consider.
Note that the video doesn't really start until 1:40 so fast forward to skip the static screen.
Monday, June 29, 2020
New 70cms repeater in the west of Ireland to improve coverage of the Southern Ireland Repeater Network
The Southern Ireland Repeater Network is made of seven interlinked repeaters on 2-metres and 70-cms and covers the southern half of Ireland. The coverage map as of June 2020 is shown below...
There are now plans to fit a new 70-cms repeater on the summit of Mahera in Co.Clare in the west of Ireland. This is an excellent site in terms of coverage and is one of the main transmission sites used by the state broadcaster RTE for radio and TV.
An approximate coverage map of the new proposed 433 MHz repeater is shown below....
The most significant change is that it will add Galway City to the Southern Ireland Repeater Network which is a welcome development.
The eastern part of Limerick City should also be covered although Woodcock Hill will screen signals to the western part of the city.
The coverage map also suggests very good coverage of the main road from Limerick to Galway as well as the eastern part of Co.Galway and the part of the midlands.
From my understanding, the new repeater will be installed once the travel restrictions for COVID-19 are eased.
Link...
1) Southern Ireland Repeater Network
There are now plans to fit a new 70-cms repeater on the summit of Mahera in Co.Clare in the west of Ireland. This is an excellent site in terms of coverage and is one of the main transmission sites used by the state broadcaster RTE for radio and TV.
An approximate coverage map of the new proposed 433 MHz repeater is shown below....
The most significant change is that it will add Galway City to the Southern Ireland Repeater Network which is a welcome development.
The eastern part of Limerick City should also be covered although Woodcock Hill will screen signals to the western part of the city.
The coverage map also suggests very good coverage of the main road from Limerick to Galway as well as the eastern part of Co.Galway and the part of the midlands.
From my understanding, the new repeater will be installed once the travel restrictions for COVID-19 are eased.
Link...
1) Southern Ireland Repeater Network
Sunday, June 28, 2020
6000 km plus contact made between the Canary Islands & Kazakhstan on 70 MHz - 18th June 2019
I recently came across details of a remarkable 70 MHz contact that was made on the 18th of June 2019 between EA8DBM in the Canary Islands and UN7MBH in Kazakhstan. It's possible that someone hadn't noticed the date on the FT8 screen capture when posted online and thought it was from 2020 instead.
Despite the fact that it's over a year old, it was still an interesting contact as it was in the region of 6,112 kms. As you can see from the screenshot below, the contact was made via the FT8 digital mode.
While most Sporadic-E contacts on 70 MHz might be in the region of say 1500 to 2200 kms, the 6000 km plus distance for this contact suggests that it may have been triple hop Sporadic-E.
Triple hop Sporadic-E on 50 MHz is interesting but not that unusual. After all, most of the 6-metre contacts between Europe and the USA are triple hop or more.
However as the frequency get higher, a higher level of ionisation is required. At 70 MHz, single hop Sporadic-E is very common, double hop is a more unusual but triple hop is more exceptional.
I searched on the net for more information on this remarkable contact but there didn't seem to be anything about it. I thought I'd make a post about it so that at least a record of it now exists.
I know that there have been triple hop contacts from the north-west of Europe to the Arabian Peninsula but I don't think any of those exceed 6000 kms.
Saturday, June 27, 2020
RSGB video on VHF Propagation
The RSGB recently released a video on YouTube which outlines the basics of VHF propagation. While it doesn't go into any great detail, it is a good primer on the subject.
"Steve Nichols, G0KYA - Chair of the RSGB Propagation Studies Committee - narrates this presentation about VHF propagation. The presentation was written by John Worsnop, G4BAO and the RSGB would like to thank Mike Willis, G0MJW for allowing use of his charts and diagrams."
"Steve Nichols, G0KYA - Chair of the RSGB Propagation Studies Committee - narrates this presentation about VHF propagation. The presentation was written by John Worsnop, G4BAO and the RSGB would like to thank Mike Willis, G0MJW for allowing use of his charts and diagrams."
Global Magnetic Anomaly on the 23rd of June 2020...
It has been reported that there was a Global Magnetic Anomaly on the 23rd of June 2020. Starting at about 06:30 UTC, there was a period of about 30 minutes where the magnetic field oscillated like a sine wave with a period of about 10 minutes.
Scientists call this phenomenon a "pulsation continuous" or "Pc" for short.
SpaceWeather describes as... "Imagine blowing across a piece of paper, making it flutter with your breath. Solar wind can have a similar effect on magnetic fields. Pc waves are essentially flutters propagating down the flanks of Earth's magnetosphere excited by the breath of the sun. During more active phases of the solar cycle, these flutters are easily lost in the noise of rambunctious geomagnetic activity. But during the extreme quiet of Solar Minimum, such waves can make themselves "heard" like a pin dropping in an silent room."
Pc waves are classified into 5 types depending on their period. The 10-minute wave on June 23rd falls into category Pc5. Slow Pc5 waves have been linked to a loss of particles from the van Allen radiation belts. Energetic electrons surf these waves down into Earth’s atmosphere, where they dissipate harmlessly.
I looked back at my WSPR reports for 28 MHz but didn't see anything unusual. Perhaps it might have had more of an impact on the lower bands.
Links...
1) Magnetic Pulsations
Scientists call this phenomenon a "pulsation continuous" or "Pc" for short.
SpaceWeather describes as... "Imagine blowing across a piece of paper, making it flutter with your breath. Solar wind can have a similar effect on magnetic fields. Pc waves are essentially flutters propagating down the flanks of Earth's magnetosphere excited by the breath of the sun. During more active phases of the solar cycle, these flutters are easily lost in the noise of rambunctious geomagnetic activity. But during the extreme quiet of Solar Minimum, such waves can make themselves "heard" like a pin dropping in an silent room."
Image from Stuart Green |
Pc waves are classified into 5 types depending on their period. The 10-minute wave on June 23rd falls into category Pc5. Slow Pc5 waves have been linked to a loss of particles from the van Allen radiation belts. Energetic electrons surf these waves down into Earth’s atmosphere, where they dissipate harmlessly.
I looked back at my WSPR reports for 28 MHz but didn't see anything unusual. Perhaps it might have had more of an impact on the lower bands.
Links...
1) Magnetic Pulsations
Tuesday, June 23, 2020
4000 km+ VHF path from Cape Verde to the UK opens up - June 2020
On the 23rd of June 2020, the VHF path from Cape Verde Islands off the west coast of Africa to the UK opened up again. The following stations in the UK and France reported D4VHF on FT8 on 144 MHz... Updates below...
Rcvr Band Mode Distance Time (UTC)
G4LOH 2m FT8 4098 km 18:23:14
GW4VXE 2m FT8 4280 km 18:15:12
G7RAU 2m FT8 4086 km 17:39:14
F8DBF 2m FT8 3963 km 17:15:44
G3NJV 2m FT8 4090 km 16:23:14
GW6TEO 2m FT8 4249 km 15:45:14
G4RRA 2m FT8 4211 km 15:33:14
GW7SMV 2m FT8 4317 km 15:33:14
M0BKV 2m FT8 4181 km 15:30:14
G8IXN 2m FT8 4110 km 15:04:44
G4ELI 2m FT8 4101 km 15:04:44
As can be seen from the location of the stations, this seems to be the usual maritime duct which can last for days.
The DX spots from the cluster shows that D4VHF was on SSB as well and they were also on 432 MHz...
G4LOH 432200.0 D4VHF 16:21 23 Jun IO70JC HK76MU 57 ssb Cape Verde
G7RAU 144174.0 D4VHF 16:11 23 Jun IN79JX HK76MU 432100 ft8 9+ Cape Verde
G4RRA 144174.0 D4VHF 15:48 23 Jun IO80BS
GW6TEO 144174.0 D4VHF 15:41 23 Jun IO71LPHK76MU tnx gl Cape Verde
GW7SMV 144174.0 D4VHF 15:34 23 Jun hrd cq -18 Cape Verde
G7RAU 432100.0 D4VHF 15:34 23 Jun IN79JX HK76MU +17 ft8, gl Cape Verde
G7RAU 144174.0 D4VHF 14:50 23 Jun IN79JX
G4LOH 144174.0 D4VHF 14:32 23 Jun IO70JC HK76MU 59+20dB CQ Cape Verde
GW0KZG 144174.0 D4VHF 14:31 23 Jun IO71LW
The tropo prediction map from Pascal, F5LEN shows that the path is open...
If you are used to VHF reports then you'll know that this path opens quiet often. It's easy to be blasé about it but it's worth remembering that the stations shown above in the UK are in the region of 4100 to 4300 kms from Cape Verde Islands.
That's the equivalent distance from London to Nova Scotia in Canada... and this is on 144 & 432 MHz!
The path from the UK to Cape Verde looks reasonable for the 24th & 25th of June before disappearing on the 26th.
Wed 24th June 2020...
It looks as if the signal from Cape Verde Islands reached the east of England...
D4VHF G4LOH 2m FT8 4098 km 15:03:14
G4CDN D4VHF 2m FT8 4613 km 07:42:56
D4VHF G4CDN 2m FT8 4613 km 07:40:14
D4VHF G4PIQ 2m FT8 4546 km 03:48:15
Note the distance for G4CDN... 4613kms!... on 144 MHz!
In the evening, there was an opening to Rome...
D4VHF IZ0UME 2m FT8 4521 km 18:54:14
IZ0UME D4VHF 2m FT8 4521 km 18:48:26
EA8CDG D4VHF 2m FT8 1546 km 18:45:26
D4VHF IW0FFK 2m FT8 4505 km 18:44:14
Another amazing distance... 4521kms. Tropo all the way or tropo & Sp-E?
North Europe to Cape Verde???....... Stations in North and Central Europe should be on the lookout for a Sporadic-E opening to the Iberian Peninsula over the next week. There is a good chance that signals would couple into the marine duct there off the south-west coast to travel onwards to Cape Verde.
Link...
1) Tropo map from F5LEN
Reception video of S50B in Slovenia on 40 MHz - 22nd June 2020
Up to now, I've seen videos online of some of the beacons on the 40 MHz being heard. This is I believe the first reception video of someone actually talking on the new 8-metre band.
To put everything into context, I have generated a map as seen above.
Borut, S50B in Slovenia heard the Irish beacon near Dublin on 40.013 MHz and then went on to work Lloyd, EI7HBB in the west of Ireland on 40.680 MHz. This distance is about 1800kms.
Paul, G7PUV in the south-east of England was monitoring the band with an SDR receiver which had the ability to record everything on the band.
As the map shows, G7PUV is about 1200kms from S50B which is a typical distance for Sporadic-E on 40 MHz with a good opening. EI7HBB on the other hand is just 600kms away and well inside the skip zone of Sp-E. It might be possible for G7PUV to hear EI7HBB via Sporadic-E but it would need an intense opening.
As a result, the video from G7PUV just has the voice of S50B and EI7HBB is missing. It also has a sample of the many noises to he heard in the ISM band on 40 MHz.
Monday, June 22, 2020
Irish Amateur Radio Licence Exams - July/August 2020
Following the postponement of the exam scheduled for May, exams have now been arranged at venues in Dublin, Cork and Galway.
Dates for the next exams
Dublin: Saturday 25th July at 2.00pm in the Maldron Hotel, Tallaght, Dublin 24. Latest date for receipt of applications is Wednesday 15th July
Cork: Saturday 8th August at 2.00pm in the Radisson Blu Hotel, Ditchley House, Little Island, Cork. Latest date for receipt of applications is Wednesday 29th July
Galway: Saturday 15th August at 2.00pm in the Menlo Park Hotel, Terryland, Headford Road, Galway. Latest date for receipt of applications is Wednesday 5th August
See www.irts.ie/exam for full details of these exams, including the application process and latest dates for receipt of applications.
Saturday, June 20, 2020
EI1KNH - Update on the new Irish beacon on 60 MHz
Back in early 2018, the 60 MHz (5-metre) band was allocated to radio amateurs in Ireland (EI) on a secondary non-interference basis. Now we have news that the very first beacon on 60 MHz is operational! See updates below...
The new beacon is operational since the 16th of December 2019 and has the call EI1KNH.
It is on 60.013 MHz and runs 25 watts into a vertical folded dipole. This is currently the only 5-metre beacon operational in the world.
The new 5-metre beacon is co-sited with some of the existing Irish beacons - EI0SIX on 50 MHz, EI4RF on 70 MHz. The elevated site has a locator of IO63VE and is located about 20 kms to the south of Dublin.
An 8-metre beacon operating on 40.013 MHz from the same site became operational in May of 2020 with an output power of 40 watts.
The photo above shows the vertical folded dipole for the 60 MHz beacon and the 40 MHz vertical for the 8-metre beacon.
* * *
Update : 20th June 2020 - FT8 replaces PI4 - Tim, EI4GNB reports that the new configuration for the EI1KNH 5-metre beacon in FT8 - CW - Carrier, with FT8 being in the first period of every minute. There are no breaks, just 60 phases an hour non-stop. This should make it easier for people to listen for it as there is a huge user base running the FT8 and WSJT-X software.
Previously it was running PI4 which is a specialised digital mode for beacons.
If anyone hearing the beacon tunes to 60.012 MHz USB, they should see FT8 decode at 1240 Hz.
Tim writes..."It is hoped that the FT8 addition will encourage more people to check for the beacon, it being a simple task of adding the 60.012 frequency to their software's FREQUENCIES list, as ALL REGIONS and ALL MODES, then they can just quickly flip over when working ft8 on 6m to see if the MUF is rising to at least 60 MHz."
* * *
The 60 MHz beacon transmits on the digital PI4 mode and CW. Details below...
PI4 + CW + Carrier 00111 (1st, 2nd & 3rd Minute of every 5 minutes) Synchronised Beacon Project (SBP)
The RF for the beacon is generated by an RFZero module running about 20 milliwatts (+13dBm).
This is then fed into a homebrew amplifier with an RA30H0608 PA stage generating 25 watts of RF.
This is then fed into a homebrew band pass filter before going to the vertical folded dipole.
Expected Range???..... What range might be expected from a beacon on 60 MHz? Considering it a weak signal mode, a tropo range of somewhere in the range of 200 kms might be expected. Perhaps up to 400 kms during times of high pressure.
It's important to note however that the Dublin and Wicklow mountains which are just to the west attenuate the signals in that direction. The path across to the west coast of Wales is much better.
A good guide would be the other beacons on 50 MHz and 70 MHz. If you can hear those then there is a reasonable chance of hearing the 60 MHz beacon.
Sporadic-E Range... It's certain that the 60 MHz beacon will be heard in Europe during the Sporadic-E season from late April to mid-August.
The map below shows the approximate limit of one hop Sporadic-E. It's likely that stations in the Baltic states, Poland, Hungary, Austria, Italy and the south of Spain should be able to hear it on a regular basis.
When conditions are really good, stations in France, Germany, Denmark, Sweden and Norway should be able to hear it.
Shorter skip than that might be a problem though. If it's is exceptional then the skip might shorten to say the Netherlands. I suspect that most of the UK will be in the skip zone for Sporadic-E.
North America???.... There is every chance that the beacon could be heard in North America via multi-hop Sporadic-E. It just needs someone over there to make the effort.
Reports... Reception reports should be sent to Tim EI4GNB. Look up EI1KNH on https://www.qrz.com/
The new beacon is operational since the 16th of December 2019 and has the call EI1KNH.
It is on 60.013 MHz and runs 25 watts into a vertical folded dipole. This is currently the only 5-metre beacon operational in the world.
The new 5-metre beacon is co-sited with some of the existing Irish beacons - EI0SIX on 50 MHz, EI4RF on 70 MHz. The elevated site has a locator of IO63VE and is located about 20 kms to the south of Dublin.
An 8-metre beacon operating on 40.013 MHz from the same site became operational in May of 2020 with an output power of 40 watts.
The photo above shows the vertical folded dipole for the 60 MHz beacon and the 40 MHz vertical for the 8-metre beacon.
* * *
Update : 20th June 2020 - FT8 replaces PI4 - Tim, EI4GNB reports that the new configuration for the EI1KNH 5-metre beacon in FT8 - CW - Carrier, with FT8 being in the first period of every minute. There are no breaks, just 60 phases an hour non-stop. This should make it easier for people to listen for it as there is a huge user base running the FT8 and WSJT-X software.
Previously it was running PI4 which is a specialised digital mode for beacons.
If anyone hearing the beacon tunes to 60.012 MHz USB, they should see FT8 decode at 1240 Hz.
Tim writes..."It is hoped that the FT8 addition will encourage more people to check for the beacon, it being a simple task of adding the 60.012 frequency to their software's FREQUENCIES list, as ALL REGIONS and ALL MODES, then they can just quickly flip over when working ft8 on 6m to see if the MUF is rising to at least 60 MHz."
PI4 + CW + Carrier 00111 (1st, 2nd & 3rd Minute of every 5 minutes) Synchronised Beacon Project (SBP)
The RF for the beacon is generated by an RFZero module running about 20 milliwatts (+13dBm).
This is then fed into a homebrew amplifier with an RA30H0608 PA stage generating 25 watts of RF.
This is then fed into a homebrew band pass filter before going to the vertical folded dipole.
Expected Range???..... What range might be expected from a beacon on 60 MHz? Considering it a weak signal mode, a tropo range of somewhere in the range of 200 kms might be expected. Perhaps up to 400 kms during times of high pressure.
It's important to note however that the Dublin and Wicklow mountains which are just to the west attenuate the signals in that direction. The path across to the west coast of Wales is much better.
A good guide would be the other beacons on 50 MHz and 70 MHz. If you can hear those then there is a reasonable chance of hearing the 60 MHz beacon.
Sporadic-E Range... It's certain that the 60 MHz beacon will be heard in Europe during the Sporadic-E season from late April to mid-August.
The map below shows the approximate limit of one hop Sporadic-E. It's likely that stations in the Baltic states, Poland, Hungary, Austria, Italy and the south of Spain should be able to hear it on a regular basis.
When conditions are really good, stations in France, Germany, Denmark, Sweden and Norway should be able to hear it.
Shorter skip than that might be a problem though. If it's is exceptional then the skip might shorten to say the Netherlands. I suspect that most of the UK will be in the skip zone for Sporadic-E.
North America???.... There is every chance that the beacon could be heard in North America via multi-hop Sporadic-E. It just needs someone over there to make the effort.
Reports... Reception reports should be sent to Tim EI4GNB. Look up EI1KNH on https://www.qrz.com/
Donation to the Southern Ireland Repeater Group - June 2020
Regular visitors to the blog will have noticed that I had Google Ads enabled on the site. When someone clicks on one of those adverts, Google makes a few cents and I make a few cents.
Considering that amateur radio is a niche subject and the level of traffic to the blog is pretty modest, the earnings potential is somewhat limited. Still, over time all of those occasional clicks and cents add up.
I decided a long time ago that I would enable the adverts for two reasons...
1) Google and their Blogger platform host the site for free and they deserve to make something from it.
2) Any money that I would make would go back into the blog or something radio related.
On that basis, I decided to use part of the advertising earnings to support the Southern Ireland Repeater Group by donating €30 online. As outlined in a previous post, they have a network of analogue and digital repeaters across the southern half of Ireland and are very proactive in improving the network.
If anyone else would like to make a donation then you can find the details HERE
Friday, June 19, 2020
Slideshow presentation on the Southern Ireland Repeater Network
The AGM of the Irish Radio Transmitters Society was scheduled to take place in April of this year but it had to be cancelled due to the COVID-19 pandemic.
As part of the AGM, the Southern Ireland Repeater Group were due to give a presentation on their network which spans the southern half of Ireland. The talk however is available as a slideshow and you can view it HERE
Link...
1) Southern Ireland Repeater Group website
Wednesday, June 17, 2020
First contact between Ireland & Slovenia made on the 40 MHz band - 15th June 2020
As of June 2020, just three countries in Europe have access to the 40 MHz band...Ireland (EI), Lithuania (LY) and Slovenia (S5).
At the end of April 2020, EI4GNB in Ireland made the first 40 MHz contact with LY2YR in Lithuania. On the 13th of June 2020, LY2YR made the first 40 MHz contact with S50B in Slovenia.
Just two days later on the 15th of June 2020, the third 40 MHz first occurred when Tim, EI4GNB in Ireland made contact with Borut, S50B in Slovenia.
The initial contact was made on the FT8 digital mode followed by FT4 and JT65.
EI4GNB and S50B then went on to complete a voice contact on SSB with 5/5 reports each way.
The mode of propagation for the contact was via Sporadic-E and the distance was just under 1660 kms.
The contact was made on 40.680 MHz in the middle of the ISM (Industrial, Scientific, Medical) band. Both Tim and Borut noted a lot of interference from digital noises on the ISM band (40.660-40.700 MHz) so it looks like the 8-metre allocation in Slovenia is prone to interference.
For the contact, EI4GNB was running 50 watts from an ICOM IC-7100 to a 2-element Quad for 8-metres. S50B was also running 50 watts from an ICOM IC-7100 but to a Sirio vertical for 40 MHz.
Report from Borut, S50B... At about 17:00 UTC, I worked many stations on 50 MHz from the USA. At 17:30, the opening to North America died out but I began to hear many stations on 6m from England (G), Wales (GW) and Ireland (EI).
I immediately went to the 8-metre band and heard the Irish beacon EI1KNH on 40.013 MHz. I sent SMS messages to EI4GNB and EI7HBB but got no response.
About 15 minutes later, Tim EI4GNB called me on FT8 on 40.680 MHz. After that, we went on to complete contacts on FT4, JT65 and SSB.
I also tried to make contact with Lloyd, EI7HBB in the west of Ireland for almost an hour but had no success.
Lloyd, EI7HBB also kindly sent on a reception report from his location in the west of Ireland showing reception of EI4GNB by tropo and S50B by Sporadic-E.
As can be seen from the screen grab, both stations at -17dB and -10dB were quiet weak.
In 2019, we saw reports of crossband contacts being made between Ireland and other European countries. In 2020, we saw the welcome appearance of two more countries who could transmit on the 8-metre band. Hopefully these results will encourage other radio amateurs around Europe to try and get permission from their respective regulatory authorities for the band.
Links...
1) For more information on the new 8-metre band, see the 40 MHz page... https://ei7gl.blogspot.com/p/40-mhz.html
At the end of April 2020, EI4GNB in Ireland made the first 40 MHz contact with LY2YR in Lithuania. On the 13th of June 2020, LY2YR made the first 40 MHz contact with S50B in Slovenia.
Just two days later on the 15th of June 2020, the third 40 MHz first occurred when Tim, EI4GNB in Ireland made contact with Borut, S50B in Slovenia.
The initial contact was made on the FT8 digital mode followed by FT4 and JT65.
Screenshot from EI4GNB showing the contacts made on FT8, FT4 & JT65 |
The mode of propagation for the contact was via Sporadic-E and the distance was just under 1660 kms.
The contact was made on 40.680 MHz in the middle of the ISM (Industrial, Scientific, Medical) band. Both Tim and Borut noted a lot of interference from digital noises on the ISM band (40.660-40.700 MHz) so it looks like the 8-metre allocation in Slovenia is prone to interference.
For the contact, EI4GNB was running 50 watts from an ICOM IC-7100 to a 2-element Quad for 8-metres. S50B was also running 50 watts from an ICOM IC-7100 but to a Sirio vertical for 40 MHz.
Report from Borut, S50B... At about 17:00 UTC, I worked many stations on 50 MHz from the USA. At 17:30, the opening to North America died out but I began to hear many stations on 6m from England (G), Wales (GW) and Ireland (EI).
I immediately went to the 8-metre band and heard the Irish beacon EI1KNH on 40.013 MHz. I sent SMS messages to EI4GNB and EI7HBB but got no response.
About 15 minutes later, Tim EI4GNB called me on FT8 on 40.680 MHz. After that, we went on to complete contacts on FT4, JT65 and SSB.
I also tried to make contact with Lloyd, EI7HBB in the west of Ireland for almost an hour but had no success.
Screenshot from S50B of the contact |
As can be seen from the screen grab, both stations at -17dB and -10dB were quiet weak.
In 2019, we saw reports of crossband contacts being made between Ireland and other European countries. In 2020, we saw the welcome appearance of two more countries who could transmit on the 8-metre band. Hopefully these results will encourage other radio amateurs around Europe to try and get permission from their respective regulatory authorities for the band.
Links...
1) For more information on the new 8-metre band, see the 40 MHz page... https://ei7gl.blogspot.com/p/40-mhz.html
Sunday, June 14, 2020
First contact between Lithuania and Slovenia made on the new 40 MHz band - 13th June 2020
At the end of April 2020, LY2YR in Lithuania made a contact with EI4GNB in Ireland for the first LY-EI QSO on the new 40 MHz amateur band.
Gintas, LY2YR achieved another first for the 8-metre band when he worked Borut, S50B in Slovenia on the 13th of June 2020 using the FT8, FT4 and CW modes. The frequency used was 40.680 MHz which is in the middle of the ISM (Industrial, Scientific, Medical) band.
Even though the ISM band of 40.660 MHz to 40.700 MHz has been allocated for beacons in Slovenia since 1998, it was only this year that the licencing authority there clarified that radio amateurs could make contacts as well.
The contact between LY2YR and S50B was approximately 1270 kms and the propagation mode was Sporadic-E. Even though the distance is pretty normal for Sporadic-E, there were some difficulties due to some 1000-metre high mountains just a few kms from S50B's location. Both stations had to wait until the Sporadic-E was strong enough to overcome the path loss.
LY2YR also completed an FT8 contact with S50TG, the 17-year old son of S50B.
For the first Lithuania to Slovenia 8-metre contact, LY2YR was using a YAESU FT-200 and a Hexbeam for 28 MHz/50 MHz.
S50B was using an ICOM IC-7100 with about 100 watts into a SIRIO vertical for 8-metres.
S50B is now looking to make the first 40 MHz contact with Ireland.
Links...
1) For more information on the new 8-metre band, see the 40 MHz page... https://ei7gl.blogspot.com/p/40-mhz.html
Wednesday, June 10, 2020
WSPR balloon on 20m over the Arctic - 10th June 2020
On the morning of the 10th of June, I left the radio monitoring the WSPR frequency on 20m to see if I would hear anything special. I noted two signals...
Australia... The first was the signal from VK3MO and VK3QN in Australia, always interesting because of the distance. I'm not 100% sure though if they were short path as shown on the map or long path. Might be something worth checking another time.
The one that really caught my eye was the VE3KCL callsign with the strange locator. I assumed at first a decoding error but no, it turns out to be a very small WSPR transmitter hung underneath a helium balloon over the Arctic Ocean!
As of the evening of the 10th of June, it was at an altitude of 10,000 metres, in constant sunlight, has a temperature of minus 6 deg C and is travelling at 18 knots.
It sends out a WSPR signals on 20m with a power output of 10 milliwatts. It was launched on the 16th of May 2020 and has is now starting its third circumnavigation of the planet.
More info here... http://qrp-labs.com/flights/u4b9.html
There are some of the WSPR decodes that I got which shows the locator square changing...
Timestamp Call MHz SNR Drift Grid Pwr Reporter RGrid km az
2020-06-10 20:58 VE3KCL 14.097177 -30 0 MR20 0.01 EI7GL IO51tu 4047 266
2020-06-10 20:38 VE3KCL 14.097178 -29 0 MR10 0.01 EI7GL IO51tu 4011 264
2020-06-10 19:48 VE3KCL 14.097178 -25 0 MR11 0.01 EI7GL IO51tu 4024 262
2020-06-10 18:38 VE3KCL 14.097184 -25 0 MR01 0.01 EI7GL IO51tu 3992 260
In addition to the QSPR signal, it is also sending out a QRSS signal in the form of a balloon!
The image I got a grab of isn't great but you can make out the circle in the waterfall.
Australia... The first was the signal from VK3MO and VK3QN in Australia, always interesting because of the distance. I'm not 100% sure though if they were short path as shown on the map or long path. Might be something worth checking another time.
The one that really caught my eye was the VE3KCL callsign with the strange locator. I assumed at first a decoding error but no, it turns out to be a very small WSPR transmitter hung underneath a helium balloon over the Arctic Ocean!
As of the evening of the 10th of June, it was at an altitude of 10,000 metres, in constant sunlight, has a temperature of minus 6 deg C and is travelling at 18 knots.
It sends out a WSPR signals on 20m with a power output of 10 milliwatts. It was launched on the 16th of May 2020 and has is now starting its third circumnavigation of the planet.
More info here... http://qrp-labs.com/flights/u4b9.html
There are some of the WSPR decodes that I got which shows the locator square changing...
Timestamp Call MHz SNR Drift Grid Pwr Reporter RGrid km az
2020-06-10 20:58 VE3KCL 14.097177 -30 0 MR20 0.01 EI7GL IO51tu 4047 266
2020-06-10 20:38 VE3KCL 14.097178 -29 0 MR10 0.01 EI7GL IO51tu 4011 264
2020-06-10 19:48 VE3KCL 14.097178 -25 0 MR11 0.01 EI7GL IO51tu 4024 262
2020-06-10 18:38 VE3KCL 14.097184 -25 0 MR01 0.01 EI7GL IO51tu 3992 260
In addition to the QSPR signal, it is also sending out a QRSS signal in the form of a balloon!
The image I got a grab of isn't great but you can make out the circle in the waterfall.
Summer 2020 edition of ECHO IRELAND now available for IRTS members to download
The PDF version of the Summer 2020 edition of ECHO IRELAND, the IRTS newsletter is now available for members to download... www.irts.ie/echo/download.html
Tuesday, June 9, 2020
Illegal Fishing Buoy on the 28 MHz WSPR Frequency
Back in June of 2018, I had a post up about how I had noticed an illegal fishing buoy on the FT8 frequency of 28.074 MHz. Today, I noticed one on the WSPR frequency of 28.1246 MHz.
Truth be told, these things are all over the bottom of the 10-metre band and it's not hard to stumble across them.
The image above shows the fishing buoy on the waterfall display of the WSJT-X programme. It turns on as a carrier which rapidly drifts upwards, settles down and finally gives an ID in morse. The whole transmission lasts for about 10 seconds.
I was listening one day on 28.200 MHz for the International Beacon Project cluster of beacons and sure enough, there was one there as well.
From what I understand, they are used to mark the position of fishing nets at sea and are almost impossible to police or regulate.
Truth be told, these things are all over the bottom of the 10-metre band and it's not hard to stumble across them.
The image above shows the fishing buoy on the waterfall display of the WSJT-X programme. It turns on as a carrier which rapidly drifts upwards, settles down and finally gives an ID in morse. The whole transmission lasts for about 10 seconds.
I was listening one day on 28.200 MHz for the International Beacon Project cluster of beacons and sure enough, there was one there as well.
From what I understand, they are used to mark the position of fishing nets at sea and are almost impossible to police or regulate.
Monday, June 8, 2020
Trans-Atlantic opening on 28 MHz - Sun 7th June 2020
There was a nice trans-Atlantic opening on 28 MHz and 50 MHz late on Sunday the 7th of June 2020. I had no real interest in trying to make any contacts so I left the radio monitoring the WSPR frequency on 28.1246 MHz.
WSPR signals heard...
Timestamp Call MHz SNR Drift Grid Pwr Reporter RGrid km
2020-06-07 23:40 W8AC 28.126032 -24 0 EN91jm 5 EI7GL IO51tu 5434
2020-06-07 23:28 W8AC 28.126032 -26 0 EN91jm 5 EI7GL IO51tu 5434
2020-06-07 23:24 W8EDU 28.126102 -26 0 EN91fm 5 EI7GL IO51tu 5455
2020-06-07 23:12 W8EDU 28.126102 -23 0 EN91fm 5 EI7GL IO51tu 5455
2020-06-07 23:10 W8AC 28.126032 -25 0 EN91jm 5 EI7GL IO51tu 5434
2020-06-07 23:04 W8EDU 28.126102 -26 0 EN91fm 5 EI7GL IO51tu 5455
2020-06-07 22:58 WA9WTK 28.126062 -23 0 FN42fk 10 EI7GL IO51tu 4734
2020-06-07 22:58 WB8ILI 28.126083 -25 -1 EN82pq 5 EI7GL IO51tu 5451
2020-06-07 22:56 W8EDU 28.126102 -22 0 EN91fm 5 EI7GL IO51tu 5455
2020-06-07 22:18 WA3DNM 28.126074 -18 0 FM29fw 5 EI7GL IO51tu 5168
2020-06-07 22:10 VE1VDM 28.126125 -26 0 FN85ij 2 EI7GL IO51tu 4001
2020-06-07 22:00 VE1VDM 28.126125 -23 0 FN85ij 2 EI7GL IO51tu 4001
2020-06-07 21:58 WA9WTK 28.126063 -22 0 FN42fk 10 EI7GL IO51tu 4734
2020-06-07 21:50 VE1VDM 28.126125 -21 -1 FN85ij 2 EI7GL IO51tu 4001
2020-06-07 21:40 WA3DNM 28.126075 -17 0 FM29fw 5 EI7GL IO51tu 5168
2020-06-07 21:40 VE1VDM 28.126124 -23 0 FN85ij 2 EI7GL IO51tu 4001
2020-06-07 21:38 WA3DNM 28.126075 -15 0 FM29fw 5 EI7GL IO51tu 5168
2020-06-07 21:30 VE1VDM 28.126124 -22 -1 FN85ij 2 EI7GL IO51tu 4001
VE1VDM was the first signal heard at 21:30 UTC and the last trans-Atlantic signal was from W8AC in Ohio at 23:40 UTC.
Most of the stations were running 4, 5 or 10 watts. The strongest SNR (Signal to Noise ratio) was -15dB which would have meant that it was buried in the noise and barely perceptible by ear.
I suspect the signals from VE1VDM may have been double hop Sporadic-E while the US stations were triple hop.
QRSS... Most the QRSS (very slow morse) transmissions from North America are just below the WSPR frequency. This allow you to look at the WSPR waterfall display in WSJT-X and see if there are any QRSS signals there.
As soon as I heard VE1VDM in Nova Scotia on WSPR, I opened up the SpectrumLab programme to take this screen grab...
In the graphic above, the vertical dotted lines mark 5 minutes of time so the scan from left to right took about 20 minutes. You wouldn't want to be in a rush to go anywhere with QRSS 😊
The signal from VE1VDM was actually stronger before this grab was taken so I would guess the QRSS signal is equivalent to roughly a -22dB WSPR signal. This seems to be about the limit of where a QRSS signal can be seen properly.
The really interesting signal though is the 100 milliawatt one. If you know the QRSS callsign in advance, you can infer the relevant information from the fragments on the screen even when the signal is much lower.
As an aside, I did see a very weak sawtooth waveform as ell during the opening.
I'm assuming for now that it was just some sort of local interference but I took a screenshot of it just for reference.
Low Band VHF... After seeing a report on Twitter about US fire traffic on 33 MHz, I had a quick look and I did come across a weak unidentified signal on 33.900 MHz. I think I was too late though and the band was closing at that stage.
Saturday, June 6, 2020
69 MHz licence free radio band in Sweden and Finland
I'm always interested to hear about other users of the low VHF bands and it was brought to my attention recently that there was a licence free band at 69 MHz in Sweden.
I had forgotten about this band and when I listened during a recent Sporadic-E opening, I could hear a conversation in Swedish on the calling frequency of 69.1875 MHz.
I thought I'd put together a post to keep a record of the frequencies in use...
Sweden... It seems as if this band which was introduced in 2016 is intended for use by anyone with a need for two way communications without the need of getting a licence. i.e. hunters, forestry workers, farmers, etc or just people who want to communicate like on CB.
There are 8 channels at the bottom of 69 MHz with a power limit of 25 watts. These are in 12.5 kHz steps...
CH1 - 69.0125 MHz
CH2 - 69.0375 MHz
CH3 - 69.0625 MHz
CH4 - 69.0875 MHz
CH5 - 69.1125 MHz
CH6 - 69.1375 MHz
CH7 - 69.1625 MHz
CH8 - 69.1875 MHz Calling Channel
There are another 10 channels further up the band. These have no channel numbers, have a maximum output power of 5 watts and have channel steps of 6.25 MHz.
69.60625 MHz
69.61875 MHz
69.63125 MHz
69.64375 MHz
69.65625 MHz
69.66875 MHz
69.68125 MHz
69.69375 MHz
69.70625 MHz
69.71875 MHz
* * * * *
Finland... Finland has a similar system called RHA68 with channels in the 68 MHz to 72 MHz range.
Channel group A
Channel Frequency Usage Power limit
1 68.100 MHz Roadside assistance organizations 25 W
2 68.300 MHz Motor sports 25 W
3 68.425 MHz Voluntary rescue service 25 W
4 68.525 MHz Motor sports 25 W
17 68.225 MHz Voluntary rescue service 25 W
Channel group E
Channel Frequency Usage Power limit
5 68.050 MHz General use 5 W
6 68.575 MHz General use 5 W
7 68.175 MHz General use 5 W
8 67.500 MHz General use 5 W
9 71.375 MHz General use 5 W
10 71.425 MHz General use 5 W
11 71.475 MHz General use 5 W
12 71.625 MHz General use 5 W
13 70.200 MHz General use 5 W
14 71.025 MHz General use 5 W
15 71.050 MHz General use 25 W
16 71.100 MHz General use 25 W
18 68.375 MHz General use 25 W
19 71.175 MHz General use 25 W
20 71.750 MHz General use 25 W
21 71.900 MHz General use 25 W
22 71.350 MHz General use 5 W
23 71.550 MHz General use 5 W
24 71.575 MHz General use 5 W
25 71.600 MHz General use 5 W
26 72.325 MHz General use 5 W
Links...
1) Swedish 69 MHz Facebook Group (Private Facebook Group - Need to join to see posts)
Friday, June 5, 2020
Radio experiments for the Solar Eclipse on the 21st of June 2020
There is annular solar eclipse coming up on Sunday the 21st of June 2020 and the track is shown above. An annual eclipse is where the moon blocks most but not all of the light from the sun and in the centre of the path, the eclipse looks like a ring of fire.
Even though it's not a total eclipse, most of the radiation from the sun will be blocked and a group of scientists are looking for volunteers to monitor a Chinese time beacon on 10.000 MHz for any changes.
This citizen science project involves monitoring the time standard for extended periods of time using the FLDIGI software.
More info here... https://hamsci.org/june-2020-eclipse-festival-frequency-measurement
The eclipse also raises the possibility of individuals doing their own experiments. Is it possible to monitor say WSPR signals that cross the path or maybe monitoring the signal strength of a broadcast station?
It would probably involve doing some tests either side of the solar eclipse to make sure that the effects you saw were actually due to the eclipse.
The eclipse starts around 04:30 UTC and ends around 08:30 UTC. The maximum point will be over the north of India around 06:30 UTC.
Link...
1) Wikipedia link for the 2020 Solar Eclipse
Addendum...
Thursday, June 4, 2020
Video about the VK9XG expedition to Christmas Island in 2018
In October of 2018, six radio amateurs from the UK activated Christmas Island which is to the south of Indonesia in the Indian Ocean. A presentation on the expedition was given at the RSGB convention in 2019 and the RSGB have now just put it up on YouTube.
I have to admit that I have pretty much no interest in these type of expeditions but I found a few points of interest in the video.
As you can see from the map below, Christmas Island is located to the south of Indonesia.
This meant that while it was easy to work areas like Japan, it was more difficult to work Europe and North America.
As you can see from the image below, they were located next to the Indian Ocean, an ideal spot for radio.
Back in October of 2018, the Solar Flux would have been very low as we were well on the way to the bottom of the sunspot cycle. This essentially meant that the higher HF bands like 10m & 12m were very poor and most of the contacts were on 21 MHz and below.
A breakdown of the modes is... SSB 11.5%, CW 68% and FT8 20.5%. This suggests that for the SSB only operator then it was going to be hard to make a contact with them.
It also reflects the explosion of interest in what was then the new FT8 digital mode and the decline in modes like RTTY.
The use of FT allowed allowed an analysis of received signal strengths.
Those with a signal to noise ratio of 0dB and above would have supported a SSB contact.
Contacts on CW would have been possible at -12dB and above.
Those contacts below -12dB were only possible on FT8.
This reflects the poor conditions and shows again that it was tough going for the SSB only operator to catch them.
It also reflects why weak signal modes like FT8 have had such an impact as it allows those with modest stations to compete with the rest.
160 Metres... It was interesting to see how they were able to work stations in the USA and how the pattern followed the areas just before sunrise.
On a more disturbing note, there were also stations on the east coast of the USA renting out time on a remote station on the west coast to make a contact on top band.
Technically it's within the rules of the ARRL DXCC programme. Morally, it's just cheating.
Links...
1) Info on ClubLog
I have to admit that I have pretty much no interest in these type of expeditions but I found a few points of interest in the video.
As you can see from the map below, Christmas Island is located to the south of Indonesia.
This meant that while it was easy to work areas like Japan, it was more difficult to work Europe and North America.
As you can see from the image below, they were located next to the Indian Ocean, an ideal spot for radio.
Back in October of 2018, the Solar Flux would have been very low as we were well on the way to the bottom of the sunspot cycle. This essentially meant that the higher HF bands like 10m & 12m were very poor and most of the contacts were on 21 MHz and below.
A breakdown of the modes is... SSB 11.5%, CW 68% and FT8 20.5%. This suggests that for the SSB only operator then it was going to be hard to make a contact with them.
It also reflects the explosion of interest in what was then the new FT8 digital mode and the decline in modes like RTTY.
The use of FT allowed allowed an analysis of received signal strengths.
Those with a signal to noise ratio of 0dB and above would have supported a SSB contact.
Contacts on CW would have been possible at -12dB and above.
Those contacts below -12dB were only possible on FT8.
This reflects the poor conditions and shows again that it was tough going for the SSB only operator to catch them.
It also reflects why weak signal modes like FT8 have had such an impact as it allows those with modest stations to compete with the rest.
160 Metres... It was interesting to see how they were able to work stations in the USA and how the pattern followed the areas just before sunrise.
On a more disturbing note, there were also stations on the east coast of the USA renting out time on a remote station on the west coast to make a contact on top band.
Technically it's within the rules of the ARRL DXCC programme. Morally, it's just cheating.
Links...
1) Info on ClubLog
Moonbounce on 21 MHz from the worlds largest antenna array for the band!
The 21 MHz antenna array of ES5RY in Estonia is reputed to be the largest in the world for that band.
The array is made up of eight 5-element Yagi's for 15m mounted on a 70-metre tower. It has a gain of 16dBd in free space with a beamwidth of less than 30 degrees.
It has a phasing system which allows the selection of five different take-off angles.... 4, 7, 10, 15 and 30 degrees.
Here is a video of ES5RY hearing a signal coming back from the moon on 21 MHz!
This next video shows the construction of the array...
The array is made up of eight 5-element Yagi's for 15m mounted on a 70-metre tower. It has a gain of 16dBd in free space with a beamwidth of less than 30 degrees.
It has a phasing system which allows the selection of five different take-off angles.... 4, 7, 10, 15 and 30 degrees.
Here is a video of ES5RY hearing a signal coming back from the moon on 21 MHz!
This next video shows the construction of the array...
Wednesday, June 3, 2020
Amazing 5600 km opening on 144 MHz from Cape Verde Islands to Poland
This post is now in two parts.
The original post is shown in Part 1 below.
The updated information with the log from D4VHF is shown in Part 2 further down the post.
* * * * *
Part 1...
On Friday the 29th of May 2020, there was an extensive Sporadic-E opening across Europe which reached as high as 144 MHz allowing stations across the continent to make many fine contacts.
The most extraordinary contacts however was probably the opening from the Cape Verde Islands off the coast of Africa to Poland on 144 MHz. The longest path recorded seems to have been when the FT8 signals from D4VHF were heard by SP5XMU in Warsaw, a distance of just over 5,600kms.
The map above shows the stations on FT8 that reported hearing or were heard by D4VHF. The most intensive part of the Sporadic-E seems to have been along a narrow corridor stretching from Lyon in France to Warsaw in Poland.
Mode of Propagation... It seems very likely that there were two propagation modes at work for this extraordinary path from the Cape Verde Islands to Central Europe.
As shown by the tropo prediction map above courtesy of F5LEN, there is a reasonably stable maritime tropo duct from the Cape Verde Islands to south coast of Portugal, a distance of about 2,800kms.
The path from Poland to the south-west of the Iberian Peninsula was spanned by a Sporadic-E opening which was in progress across Europe at the time.
As with openings of this nature, there is always the possibility of double hop Sporadic-E which can't be discounted for a good part of the path. However, this tropo duct off the north-west coast of Africa is a remarkably steady feature and it seems to be there for a large part of the year. It's hard to imagine that it didn't play a major part in the opening.
In 2019, there were other similar mixed Sporadic-E & tropo duct openings from Cape Verde to Italy and Germany. The distances involved with this opening to Poland though are exceptional.
* * * * *
PART 2...
Update. Now that the dust has settled, we can look at the log of D4VHF and who they worked...
While many stations heard D4VHF on FT8, a much smaller number managed to make a contact.
Here is the log...
2020-05-29,10:05:15, CT1END,IM58,144.175900,FT8,-07,-04,,,
2020-05-29,11:10:00, IK4ADE,JN54,144.175900,FT8,-07,-09,,,
2020-05-29,11:57:15, IK0ZYH,JN62,144.175900,FT8,-15,-17,,,
2020-05-29,12:15:45, EA8AJC,IL18,144.175900,FT8,+28,+17,,,
2020-05-29,12:36:00, F6EAS,,144.175900,FT8,+04,+02,,,
2020-05-29,12:43:30, EC1KV,,144.175900,FT8,-15,-15,,,
2020-05-29,12:49:15, F1DUZ,IN97,144.175900,FT8,-18,-19,,,
2020-05-29,12:52:00, F6CIS,,144.175900,FT8,-15,-19,,,
2020-05-29,12:59:45, F6DBI,IN88,144.175900,FT8,-03,-07,,,
2020-05-29,13:22:30, F8DBF,IN78,144.175900,FT8,-06,-08,,,
2020-05-29,13:47:00, G4RRA,,144.175900,FT8,-15,-16,,,
2020-05-29,13:49:00, G8BCG,,144.175900,FT8,+00,-16,,,
2020-05-29,13:52:00, GW7SMV,,144.175900,FT8,-05,-16,,,
2020-05-29,13:54:30, G3NJV,IO70,144.175900,FT8,-15,-01,,,
2020-05-29,13:55:30, G7RAU,IN79,144.175900,FT8,-13,-13,,,
2020-05-29,14:19:15, CT1IUA,IM67,144.175900,FT8,-16,-12,,,
2020-05-29,15:27:00, DJ8RZ,JN58,144.175900,FT8,-08,-10,,,
2020-05-29,15:30:45, DL5MCG,,144.175900,FT8,-09,-19,,,
2020-05-29,15:34:45, I2FAK,JN45,144.175900,FT8,+10,-11,,,
2020-05-29,18:41:15, CT1ANO,IN51,144.175900,FT8,-18,-19,,,
2020-05-29,18:55:15, CU2GI,HM77,144.175900,FT8,-19,-18,,,
2020-05-30,08:39:45, EA8AIN,IL18,144.175900,FT8,-09,+08,,,
2020-05-30,16:21:30, EA7FDW,IM76,144.175900,FT8,-11,-12,,,
2020-05-30,16:44:45, EA7E,IM66,144.175900,FT8,-18,-20,,,
2020-05-30,16:49:45, CT1EYQ,IM58,144.175900,FT8,-18,-17,,,
2020-05-30,17:16:45, EC2AGL,IN91,144.175900,FT8,-06,-16,,,
2020-05-30,17:22:45, CT1ADT,IM57,144.175900,FT8,-13,-07,,,
The FT8 signals sent and received by D4VHF according to the PSK Reporter website are shown at the end of this post.
Some points...
1) SSB V FT8... For a Sporadic-E opening on 144 MHz, a mode like SSB would be much better in terms of speed. However, look at the signal strengths in the log. Most are in the minus dB range so a SSB QSO would probably have not been possible.
As for what would be a better mode is up for debate. Marginal contacts via CW? Faster digital modes like FT4? No matter what mode was used, there would have always been incomplete contacts and a limit to how many would get in the log.
2) Mode of Propagation... From what we know, there seems to be two components.
First, there is a marine duct off the west coast of Morocco which allows VHF signals to propagate from Cape Verde Islands up to the Canary Islands (1500kms), Portugal & Spain (3000kms) and the UK (4000kms).
According to one of the operators of D4VHF...Mark EA8FF, there was no tropo between D4 and EA8 or EA7 at the time. And yet, this marine duct over the sea was probably present for a good part of the path. I don't think we can discount it and yet, there must surely be Sporadic-E openings on 144 MHz in that part of the world as well? We can't always assume it's a marine duct.
While we can debate the paths from D4 to the coasts of Portugal or the south of Spain, those signals from further north were almost certainly via Sporadic-E.
The question is was it tropo & Sp-E, multi-hop Sp-E at 144 MHz?? Just in terms of probability, I personally don't believe in triple hop Sporadic-E at 144 MHz. Double maybe, triple?!?!
3) Sporadic-E to the UK... The problem with just a list of stations is that there are like data points for a graph, they don't make much sense until you draw the graph. In the same vein, when you generate a map and see the location of the stations, you can see patterns.
Again, see the map above. Note how the UK stations are strung out in a nice narrow line. This is a classic Sporadic-E footprint. The furthest station was GW7SMV at just over 4300kms.
4) Poland... The other unusual dimension to this opening was the unusual opening at the same time from Portugal to Poland. See the QSO map below from Tom, SP5MXU...
As you can see, SP5XMU was able to work stations in Portugal at a distance of almost 2800kms. What is unusual about this is that the usual maximum distance for one-hop Sporadic-E is about 2300kms. Where did the extra 500kms come from?
This is usually explained by say a tropo extension at one or both ends. Another is the possibility of chordal hop as suggested by SO3Z in the comments. In that scenario, the signal is going between two Sporadic-E clouds before returning to the ground again.
The chordal hop theory may help explain how the 144 MHz signals covered at least part of the 5600km distance from Cape Verde Islands to Poland.
Part 2 Conclusion... In the past with traditional modes like SSB and CW, we could be reasonably sure about the mode of propagation on VHF bands like 2 metres. Now with digital modes like FT8 we are seeing signals buried in the noise which makes it harder to be certain about how the signal was propagated.
I know FT8 isn't popular with everyone but the new digital modes are allowing radio amateurs to discover paths on VHF that we never knew existed.
* * * * *
Equivalent Distances... As always, it's interesting to look at some maps to put these remarkable distances in perspective.
The 5600 km distance from the Cape Verde Islands to Warsaw would reach as far north as Oslo, the capital of Norway.
It's hard to believe but the whole island of Iceland is actually closer!
From a western perspective, the equivalent distance reaches as far as Washington DC in the USA.
Remember, there are no satellites or moonbounce involved here. This is a 144 MHz signal being propagated by Sporadic-E and tropo.
What if...??? The map of the USA above suggests maybe one potential extraordinary path. From time to time, there seems to be a tropo duct across the Atlantic from Care Verde to the the Caribbean. Could this be extended even further to the west by a Sporadic-E opening at the same time???
FT8 signals heard by D4VHF...(over 3400kms)
The original post is shown in Part 1 below.
The updated information with the log from D4VHF is shown in Part 2 further down the post.
* * * * *
Part 1...
On Friday the 29th of May 2020, there was an extensive Sporadic-E opening across Europe which reached as high as 144 MHz allowing stations across the continent to make many fine contacts.
The most extraordinary contacts however was probably the opening from the Cape Verde Islands off the coast of Africa to Poland on 144 MHz. The longest path recorded seems to have been when the FT8 signals from D4VHF were heard by SP5XMU in Warsaw, a distance of just over 5,600kms.
The map above shows the stations on FT8 that reported hearing or were heard by D4VHF. The most intensive part of the Sporadic-E seems to have been along a narrow corridor stretching from Lyon in France to Warsaw in Poland.
Mode of Propagation... It seems very likely that there were two propagation modes at work for this extraordinary path from the Cape Verde Islands to Central Europe.
As shown by the tropo prediction map above courtesy of F5LEN, there is a reasonably stable maritime tropo duct from the Cape Verde Islands to south coast of Portugal, a distance of about 2,800kms.
The path from Poland to the south-west of the Iberian Peninsula was spanned by a Sporadic-E opening which was in progress across Europe at the time.
As with openings of this nature, there is always the possibility of double hop Sporadic-E which can't be discounted for a good part of the path. However, this tropo duct off the north-west coast of Africa is a remarkably steady feature and it seems to be there for a large part of the year. It's hard to imagine that it didn't play a major part in the opening.
FT8 screenshot from D4VHF |
In 2019, there were other similar mixed Sporadic-E & tropo duct openings from Cape Verde to Italy and Germany. The distances involved with this opening to Poland though are exceptional.
* * * * *
PART 2...
Update. Now that the dust has settled, we can look at the log of D4VHF and who they worked...
While many stations heard D4VHF on FT8, a much smaller number managed to make a contact.
Here is the log...
2020-05-29,10:05:15, CT1END,IM58,144.175900,FT8,-07,-04,,,
2020-05-29,11:10:00, IK4ADE,JN54,144.175900,FT8,-07,-09,,,
2020-05-29,11:57:15, IK0ZYH,JN62,144.175900,FT8,-15,-17,,,
2020-05-29,12:15:45, EA8AJC,IL18,144.175900,FT8,+28,+17,,,
2020-05-29,12:36:00, F6EAS,,144.175900,FT8,+04,+02,,,
2020-05-29,12:43:30, EC1KV,,144.175900,FT8,-15,-15,,,
2020-05-29,12:49:15, F1DUZ,IN97,144.175900,FT8,-18,-19,,,
2020-05-29,12:52:00, F6CIS,,144.175900,FT8,-15,-19,,,
2020-05-29,12:59:45, F6DBI,IN88,144.175900,FT8,-03,-07,,,
2020-05-29,13:22:30, F8DBF,IN78,144.175900,FT8,-06,-08,,,
2020-05-29,13:47:00, G4RRA,,144.175900,FT8,-15,-16,,,
2020-05-29,13:49:00, G8BCG,,144.175900,FT8,+00,-16,,,
2020-05-29,13:52:00, GW7SMV,,144.175900,FT8,-05,-16,,,
2020-05-29,13:54:30, G3NJV,IO70,144.175900,FT8,-15,-01,,,
2020-05-29,13:55:30, G7RAU,IN79,144.175900,FT8,-13,-13,,,
2020-05-29,14:19:15, CT1IUA,IM67,144.175900,FT8,-16,-12,,,
2020-05-29,15:27:00, DJ8RZ,JN58,144.175900,FT8,-08,-10,,,
2020-05-29,15:30:45, DL5MCG,,144.175900,FT8,-09,-19,,,
2020-05-29,15:34:45, I2FAK,JN45,144.175900,FT8,+10,-11,,,
2020-05-29,18:41:15, CT1ANO,IN51,144.175900,FT8,-18,-19,,,
2020-05-29,18:55:15, CU2GI,HM77,144.175900,FT8,-19,-18,,,
2020-05-30,08:39:45, EA8AIN,IL18,144.175900,FT8,-09,+08,,,
2020-05-30,16:21:30, EA7FDW,IM76,144.175900,FT8,-11,-12,,,
2020-05-30,16:44:45, EA7E,IM66,144.175900,FT8,-18,-20,,,
2020-05-30,16:49:45, CT1EYQ,IM58,144.175900,FT8,-18,-17,,,
2020-05-30,17:16:45, EC2AGL,IN91,144.175900,FT8,-06,-16,,,
2020-05-30,17:22:45, CT1ADT,IM57,144.175900,FT8,-13,-07,,,
The FT8 signals sent and received by D4VHF according to the PSK Reporter website are shown at the end of this post.
Some points...
1) SSB V FT8... For a Sporadic-E opening on 144 MHz, a mode like SSB would be much better in terms of speed. However, look at the signal strengths in the log. Most are in the minus dB range so a SSB QSO would probably have not been possible.
As for what would be a better mode is up for debate. Marginal contacts via CW? Faster digital modes like FT4? No matter what mode was used, there would have always been incomplete contacts and a limit to how many would get in the log.
2) Mode of Propagation... From what we know, there seems to be two components.
First, there is a marine duct off the west coast of Morocco which allows VHF signals to propagate from Cape Verde Islands up to the Canary Islands (1500kms), Portugal & Spain (3000kms) and the UK (4000kms).
According to one of the operators of D4VHF...Mark EA8FF, there was no tropo between D4 and EA8 or EA7 at the time. And yet, this marine duct over the sea was probably present for a good part of the path. I don't think we can discount it and yet, there must surely be Sporadic-E openings on 144 MHz in that part of the world as well? We can't always assume it's a marine duct.
While we can debate the paths from D4 to the coasts of Portugal or the south of Spain, those signals from further north were almost certainly via Sporadic-E.
The question is was it tropo & Sp-E, multi-hop Sp-E at 144 MHz?? Just in terms of probability, I personally don't believe in triple hop Sporadic-E at 144 MHz. Double maybe, triple?!?!
3) Sporadic-E to the UK... The problem with just a list of stations is that there are like data points for a graph, they don't make much sense until you draw the graph. In the same vein, when you generate a map and see the location of the stations, you can see patterns.
Again, see the map above. Note how the UK stations are strung out in a nice narrow line. This is a classic Sporadic-E footprint. The furthest station was GW7SMV at just over 4300kms.
4) Poland... The other unusual dimension to this opening was the unusual opening at the same time from Portugal to Poland. See the QSO map below from Tom, SP5MXU...
As you can see, SP5XMU was able to work stations in Portugal at a distance of almost 2800kms. What is unusual about this is that the usual maximum distance for one-hop Sporadic-E is about 2300kms. Where did the extra 500kms come from?
This is usually explained by say a tropo extension at one or both ends. Another is the possibility of chordal hop as suggested by SO3Z in the comments. In that scenario, the signal is going between two Sporadic-E clouds before returning to the ground again.
The chordal hop theory may help explain how the 144 MHz signals covered at least part of the 5600km distance from Cape Verde Islands to Poland.
Part 2 Conclusion... In the past with traditional modes like SSB and CW, we could be reasonably sure about the mode of propagation on VHF bands like 2 metres. Now with digital modes like FT8 we are seeing signals buried in the noise which makes it harder to be certain about how the signal was propagated.
I know FT8 isn't popular with everyone but the new digital modes are allowing radio amateurs to discover paths on VHF that we never knew existed.
* * * * *
Equivalent Distances... As always, it's interesting to look at some maps to put these remarkable distances in perspective.
The 5600 km distance from the Cape Verde Islands to Warsaw would reach as far north as Oslo, the capital of Norway.
It's hard to believe but the whole island of Iceland is actually closer!
From a western perspective, the equivalent distance reaches as far as Washington DC in the USA.
Remember, there are no satellites or moonbounce involved here. This is a 144 MHz signal being propagated by Sporadic-E and tropo.
What if...??? The map of the USA above suggests maybe one potential extraordinary path. From time to time, there seems to be a tropo duct across the Atlantic from Care Verde to the the Caribbean. Could this be extended even further to the west by a Sporadic-E opening at the same time???
FT8 signals heard by D4VHF...(over 3400kms)
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