New 2700km+ IARU Region-1 tropo record on 23cms between Ireland and the Canary Islands - 17th July 2020

On the 17th of July 2020, there was an opening between the Canary Islands and the UK & Ireland on the VHF & UHF bands. A remarkable contact was made on 1296 MHz between EA8CXN and EI2FG which turned out to be a new IARU Region-1 tropo record for the 23cms microwave band.

In a report on his website, Cesar EA8CXN reports that there was a good tropo opening on July 17, 2020,  between Ireland-England and the Canary Islands.

In the evening, EA8CXN completed contacts with G7RAU, G4LOH and EI20C (op. Mark, EI3KD) on 432 MHz. EI20C mentions that John, EI2FG is also active on 1296 MHz so tests begin.

G7RAU is the first to complete a successful contact on SSB on 1296.200 MHz using just 5 watts into a 56 element Yagi. G4LOH also completed a contact.

After a period of deep QSB, a successful SSB contact was completed with EI2FG on 23 cms with 5/1 and 5/4 reports exchanged. The distance was an amazing 2714 kms.

Not only was this the first ever contact between Ireland and Canary Islands on 1296 MHz but it was also a new IARU Region-1 tropo record for 23 cms.

The map above shows the limit of the new record. The old record of 2661 kms was set on the 14th of July 2017 between EA8AVI and M0VRL.

The map also suggests that there is plenty of scope for the record to be broken with sea paths further north to the west of Wales and up the Irish Sea.

Equipment... For the record SSB contact on 23 cms, EA8CXN was using 150 watts into a small parabolic dish which was 50 cms in diameter. The feed point for the dish was a 3-element horizontally polarized PCB Yagi.

EI2FG was using his EME station of 200 watts into a 3-metre parabolic dish. The feed point was Right-Hand Circular Polarization on transmit and Left-Hand CP on receive.

Propagation... The mode of propagation was via a maritime duct over the ocean.

This duct exists for long periods of the year between the Canary Islands and the western coast of Spain & Portugal and then gets extended sometimes further north to the UK and Ireland.

In conclusion.... To put this this record 2714 km contact on 1296 MHz, a microwave band into perspective, it's worth remembering that the distance across the North Atlantic from Ireland to Newfoundland is around 3000kms. 

It's also likely that the record distance could be exceeded further north to Wales or up the Irish Sea as outlined earlier. The biggest obstacle at the moment is probably the lack of stations on 23 cms.

If the D4VHF station on Cape Verde Islands off the coast of Africa ever became operational on 1296 MHz, the record could well be extended to about 4000 kms.

Links...

1) EA8CXN post in Spanish

432 MHz world tropo record extended even further to 4,644 kms - 1st Jan 2020

On Saturday the 28th of December 2019, Ian GM3SEK in the south-west of Scotland managed to work D41CV on 432 MHz to set a new world record for tropo on the band. The distance for this FT8 contact was an amazing 4,562 kms.

Considering the fact that it was on the 70cms band and that  the south-west coast of Scotland was one of the longest sea paths to Cape Verde Islands, it seemed as this might be a long term record.

It wasn't to be however as just a few days later on Wednesday the 1st of January 2020, Nick G4KUX in the county of Durham in the north of England managed to work D41CV also on FT8 on 432 MHz to push the record out a further 80kms or so to 4,644kms.

This is the screenshot of G4KUX having an FT8 contact with D41CV on 432 MHz.

Nick, G4KUX lives in an elevated location to the west of Bishop Auckland in County Durham in the north of England. His location is about 360 metres above sea level and he has a good take off for radio in all directions.

For the record breaking contact with D41CV, Nick was using 400 watts into a UHF Log-Periodic antenna as shown in the photo below. The suprising thing about this is that the gain of the Log-Periodic would be pretty modest and is probably no better than say a 3 or 4 element Yagi.

The gain of the Log is probably at least 10dB lower that say a box of four Yagi antennas like the ones Nick has for 144 MHz.

Mode of Propagation???... Looking at the path for the previous record contact on 432 MHz from Ian, GM3SEK in the SW of Scotland to D41CV on Cape Verde Islands then we can probably speculate that the mode of propagation was via a sea duct.

For G4KUX however, the signals had to cross over some hills and mountains in Wales and the north of England. Considering there were very good tropo conditions at the time across western Europe, it seems likely that there was an elevated duct for the most northerly part of the contact and this then coupled into a sea duct further south.

Record Limit... The map below shows the new limit of the 432 MHz tropo record.

Can the record be broken? Probably. We saw in 2019 several occasions during the year when a sea duct existed between Cape Verde Islands and the British and Irish Isles. If the only mode of propagation is via sea ducting then maybe the new record will be set from the western islands of Scotland.

What we saw in the last few days at the end of 2019 and the start of 2020 was the rarer occurrence of the sea ducting happening at the same time as an extensive tropo opening with elevated ducting. This will no doubt happen again but maybe not so often.

G4KUX contacts... This is a list of some contacts G4KUX made around the same time on FT8 on 432 MHz.

G4KUX IO94BP F6DBI IN88 FT8 -08 -15 20191229 105400  20191229 105500 70CM 432.174000  0
G4KUX IO94BP F5APQ JO00 FT8 -06 +03 20191231 153200  20191231 153400 70CM 432.174000  0
G4KUX IO94BP ON4QJ JO20 FT8 -12 -09 20191231 153500  20191231 153600 70CM 432.174000  0
G4KUX IO94BP F1ISM JN09 FT8 +03 +02 20191231 155300  20191231 155400 70CM 432.174000  0
G4KUX IO94BP ON4AOI JO21 FT8 -06 -14 20191231 160200  20191231 160400 70CM 432.174000  0 
G4KUX IO94BP F6KBF JN18 FT8 -03 -17 20191231 160500  20191231 160700 70CM 432.174000  0 
G4KUX IO94BP SP7CKH JO92 FT8 -13 -19 20200101 121100  20200101 121300 70CM 432.063000  0
G4KUX IO94BP SP2JYR JO92GP FT8 -15 -10 20200101 121400  20200101 121400 70CM 432.063000  0
G4KUX IO94BP DL1TRK JO63  FT8 -20 -14 20200101 121500  20200101 121500 70CM 432.063000  0 
G4KUX IO94BP HF1J JO73  FT8 -17 -21 20200101 151400  20200101 151700 70CM 432.063000  0 
G4KUX IO94BP DL1SUZ JO53 FT8 +00 +06 20200101 151700  20200101 151800 70CM 432.063000  0 
G4KUX IO94BP PH0TV JO32 FT8 -16 -11 20200101 152000  20200101 152100 70CM 432.063000  0 
G4KUX IO94BP D41CV HK76MU FT8 -15 -20 20200101 192900  20200101 201300 70CM 432.174000  0 

As you can see, Nick was able to work into France, Belgium, Poland, Germany and the Netherlands while there was high pressure and tropo ducting about.

All in all, an amazing week or so of propagation on the VHF and UHF bands.

Links...
a) F5LEN tropo forecasts

D41CV and GM3SEK set new 144 MHz tropo record of over 4500 kms

In what was probably the best tropo opening to Cape Verde Islands to date, Ian White GM3SEK in Scotland managed to work D41CV on the Cape Verde Islands on FT8 to set a new IARU Region-1 tropo record for 144 MHz. The contact was made on the 28th of December 2019 and the distance was estimated to be in the region of 4565 kms which is about 130 kms further than the previous record which was set by D41CV and G3SMT in September of 2018.

GM3SEK used 400 watts into an 11-element beam to complete the record contact.

A number of other stations in England, Wales, Ireland and the Isle of Man managed to complete contacts with D41CV as well.

To put the opening into context, the stations that heard D41CV on FT8 on Saturday the 28th of December 2019 are shown below. Also shown is the limit of the previous record.

What really stands out is the number of stations that heard the signal from D41CV and were further than the old record.

Of these, GD3YEO and GD6ICR both managed to complete a contact for what were probably the first ever contacts between Cape Verde Islands and the Isle of Man on 144 MHz.

John, MW1CFN on the Isle of Anglesey did not make a contact but managed to hear D41CV with a small 3-element yagi!

MI0XZZ to the north of Belfast managed to hear D41CV despite the fact that the signal had to travel over the island of Ireland.

Possibly the most interesting reception report was that of 2M0TNM in the far west of Scotland. The distance was an impressive 4,710 kms and was almost completely a sea path. If anyone is likely to break the new record then it's likely to be from there.

432 MHz... Amazingly, GM3SEK also managed to work D41CV on 432 MHz for a new world record distance for tropo. That report is in a separate post HERE.

Mode of propagation... As you'll notice, it's those with a sea path that were able to avail of the opening. It was likely to have been the usual maritime ducting.

The tropo prediction map below from Pascal, F5LEN shows the path from Cape Verde to the UK and Ireland.

Links...
1) F5LEN tropo prediction website
2) Excellent end of year tropo opening results in new world record 432 MHz contact of 4562 kms

Australian 70cms digital record extended to 2,806 kms

Early on the morning of the 5th of December 2019, there was a remarkable tropo contact between Leigh, VK2KRR and Peter, VK6KXW on 70cms across the Australian continent. The distance was 2,806 kms and crossed over the Great Australian Bight, a part of the ocean well noted for tropospheric ducting.

This was a new Australian record for a digital contact on 432 MHz as both stations were using the FT8 mode. The previous record was 2,793 kms which was set back in December of 2016.

VK6KXW was running 75 watts from an IC9700 into a single yagi. VK2KRR was also running 75 watts from an IC9700 but his antenna was a box of four yagis.

VK2KRR's box of four yagis used for the contact. Source: VK2KRR on Facebook

The time of the contact was probably also a factor as tropo ducting is often at its best very early in the morning when the atmosphere has settled down and the sun hasn't risen yet.

The current non-digital record for the 70cms band in Australia is just a bit further at 2,862 kms. This was set between VK6KXW and VK7AC on the 17th of January 2019.

While examining both of these contacts, it can be difficult to relate to the distance of 2,806 kms and just how far it is. It might be useful for stations in Europe to remember that the distance from the west coast of Ireland to Newfoundland in Canada is 3,000kms, just an extra 200 kms.

Leigh VK2KRR has a nice website with plenty of VHF info, visit https://www.vk2krr.com/

New 432 MHz station on Cape Verde Islands raises possibility of new records being set

144 & 432 MHz Yagi antennas on Cape Verde

So far in 2019, the D4C contest team on Cape Verde Islands off the west coast of Africa have made some pretty amazing contacts on 144 MHz. Using the call D41CV, they have worked across the Atlantic to the Caribbean, up to the UK, France and Ireland via marine tropo ducting and into Germany, Italy and Slovenia with a combined Sporadic-E / marine ducting mode.

Many of these contacts were well in excess of 4000 kms in distance. See links to posts HERE.

The D4C team have recently announced that they are now active on 432 MHz (70cms).

"We are now capable to be active on #70cm #432Mhz #uhf using a 16 El yagi "Pinocchio" model (wooden boom) home made. Transverter connected to @FlexRadioSystem 6600M driving a solid state PA running 100W seems working as we have worked on SSB loc IM66 for 3000 km dx #hamradio"

As the tropo prediction map from F5LEN shows below, a marine duct off the west coast of Africa seems to exist for long periods of time during the Summer and Autumn months.

This should allow D41CV on the Cape Verde Islands to work up to coastal stations in Spain and Portugal on 432 MHz, a distance of roughly 2,900 kms.

Potential for new records???

Before we look at the potential of D41CV setting new records, we should probably look first at what the current IARU Region 1 record for tropo on 432 MHz is.

Back on the 9th of July 2015, G4LOH in the south-west of England worked D44TS on 432 MHz CW. This was a sea path of roughly 4070 kms, an amazing distance for 70 cms.

This contact was as a result of the marine duct extending much further north so that it managed to get as far as England.

Just to show how good conditions were that day, here is video clip showing G4LOH hearing the D4C/B beacon on 432 MHz...



One important point here is that G4LOH worked D44TS where as D41CV is actually on a different island. As you can seen from the map below, Cape Verde is spread out over several different islands...

You'll also notice that D41CV is further south than D44TS.

If we now look at how far 4070 kms is from D41CV then we get this map...

This means that if anyone in Ireland, Wales or England managed to work D41CV on 432 MHz then it would be a new IARU Region 1 tropo record.

I would suggest that as long as there is a 432 MHz capable station active on Cape Verde Islands then this is probably a case of 'when' rather than 'if '.

Trans-Atlantic on 432 MHz???

It's hard to imagine a 70cms signal getting across the Atlantic but it's something that can't be discounted.

Earlier in June of 2019, there was a tropo duct across the Atlantic from Cape Verde to the Caribbean which lasted several days and allowed the propagation of 144 MHz signals.

If 144 MHz signals lasted for several days, was there a shorter period of time when 432 MHz signals would have propagated inside the marine duct?

If it were possible then this is what the 4070 km distance from D41CV looks like...

If a 432 MHz signal can travel 4070 kms from Cape Verde Islands to England then perhaps trans-Atlantic is not impossible?

There should be some interesting times in the months and years ahead as these possibilities are explored.

Links...
1) Archive from G4LOH's blog
2) IARU Region 1 tropo records for 432 MHz
3) F5LEN Tropo Forecast