Thursday, January 30, 2020
Video: Amateur Television on the Microwave Bands
This 39 minute talk about Amateur Television was given at the Cardiff Microwave Roundtable in the Spring of 2019 and it has just been uploaded to YouTube.
It gives a good summary of the current state of Amateur TV in the UK and the techniques and frequencies used.
Sunday, January 26, 2020
Opening to Africa and the Middle East on 28 MHz - Sun 26th Jan 2019
While the signals didn't seem that strong, 48 stations in 17 countries were heard.
There seemed to have been Sporadic-E over Europe and this then linked to paths to South Africa and the Middle East.
ZN6NL in South Africa was heard as well as 4X4MF in Israel and 9K2KH in Kuwait.
The Solar Flux was 73 which is up a tiny bit from the more usual 68 of late.
Things might start getting better as we heard towards the equinox.
Saturday, January 25, 2020
Czech RF10 Military Radio covering 44 to 54 MHz
The RF output is via a socket for a whip / long wire antenna (shown above on the far left) or via the BNC socket alongside it.
An example of the radio is shown in this LINK
While it does not cover the new 40 MHz 8-metre band, it may be of interest to those listening on the low VHF frequencies or anyone on the 50 MHz / 6-metre band.
Thanks to Robbie, EI2IP for the above link.
Additional info HERE
Saturday, January 18, 2020
Commercial Kenwood transceivers for 40 MHz
There are a large number of commercial and utility companies making use of the low VHF band in the USA from 30 to 50 MHz. Several manufacturers including Kenwood sold radios to service this market.
In the past, these were largely operating on FM but many systems are now being replaced with their digital equivalents. As a result, many old Kenwood commercial FM transceivers can be picked up on sites like eBay.
These radios are a potential source of relatively cheap FM radios for the 40 MHz (8-metre) band.
It should be noted that commercial radios are usually programmed to operate on certain frequencies. Any second hand models will need to be re-programmed.
Here are the Kenwood radios that operate on the Low VHF band.
* * * * *
Kenwood TK-190... This handheld radio comes in two versions. The TK-190K covers 29.7 to 37.0 MHz and the TK-190K2 covers 35.0 to 50.0 MHz. Both versions have an output power of 1-watt (Low) and 6-watts (High).
This radio had a list price of $643 in 2007.
* * * * *
Kenwood TK-630... This radio was released in the early 90's.
It is available with power output levels of 110 watts on FM! The TK-630 is available in three frequency ranges... 29.7 MHz to 37 MHz, 35 MHz to 43 MHz and 41 MHz to 50 MHz.
In the past, these were largely operating on FM but many systems are now being replaced with their digital equivalents. As a result, many old Kenwood commercial FM transceivers can be picked up on sites like eBay.
These radios are a potential source of relatively cheap FM radios for the 40 MHz (8-metre) band.
It should be noted that commercial radios are usually programmed to operate on certain frequencies. Any second hand models will need to be re-programmed.
Here are the Kenwood radios that operate on the Low VHF band.
* * * * *
Kenwood TK-190... This handheld radio comes in two versions. The TK-190K covers 29.7 to 37.0 MHz and the TK-190K2 covers 35.0 to 50.0 MHz. Both versions have an output power of 1-watt (Low) and 6-watts (High).
This radio had a list price of $643 in 2007.
* * * * *
Kenwood TK-630... This radio was released in the early 90's.
It is available with power output levels of 110 watts on FM! The TK-630 is available in three frequency ranges... 29.7 MHz to 37 MHz, 35 MHz to 43 MHz and 41 MHz to 50 MHz.
Friday, January 17, 2020
Winter 2019 - 2020 edition of ECHO IRELAND now available
The Winter 2019/2020 edition of ECHO IRELAND is now available for IRTS members to download in PDF format. Any member wishing to change from the print version to the electronic PDF format should contact the Membership Records Officer... www.irts.ie/officers
Thursday, January 16, 2020
ARRL release 'On the Air' magazine for beginners
In an effort to reach out to more people, the American Amateur Relay League (ARRL) have produced a new magazine aimed at beginners and those new to the hobby.
There are a number of interesting articles in it including a simple ground quarter wave ground plane antenna for 144 MHz and 432 MHz as well as a multi-band HF antenna.
From what I understand, the first one is free and future issues will be only for ARRL members.
You can view the Jan/Feb 2020 issue HERE
Wednesday, January 15, 2020
Commercial 40 MHz transceiver from a Polish company
To be more precise, the 3005-40 model comes in two variants... one can operate from 30 MHz to 41 MHz and the other one can operate from 40 to 52.5 MHz.
According to the specs, it has up to 32 channels max which suggests that it is designed to be used for a specific purpose i.e. operate on a fixed number of channels. It's not really suitable for say scanning the low VHF spectrum to see what can be heard.
It operates on FM and there is a choice of 12.5 or 25 kHz spacing. The power output is 5 to 10 watts.
The specs also say the current consumption on receive is 3.5 amps. This is 42 watts! It's very likely that it is the power consumption while transmitting.
More info about the radio can be seen on the company website HERE
I suspect that the company may only be interested in selling to companies rather than individuals but I like to keep a list of any 40 MHz equipment on the site.
Thanks to Rob PE9PE for the link for this radio.
Monday, January 13, 2020
ARRL to introduce $5 radio kits...
ARRL is developing low-cost (target $5.00), build-it-inan-hour receiver and transmitter kits. We intend to make these available at nominal cost to members and radio clubs who want to have a different “soldering experience” at their next hamfest.
In a world of smartphones and social media, the thought of talking to someone in another country over a radio is no longer the novelty that it once was.
Building kits and actually getting something to work may well appeal to a lot of people and they get to learn something in the process.
Considering the size of the ARRL, it's likely that these kits may well prove to be very popular and widely available in time. At a $5 price point, they are likely to be very basic but at least it's a start.
Source... http://www.arrl.org/files/file/QST/This%20Month%20in%20QST/February2020/February%20%20Editorial.pdf
Sunday, January 12, 2020
28 MHz wide open again - Sun 12th Jan 2020
28 MHz was wide open to Europe again today with loads of Sporadic-E signals on the band. Despite the fact that it's the middle of January, the band was as good as many days during the summer months.
The skip distance was slightly longer today compared to yesterday with not too many from the Netherlands making it through.
There were a few long distance stations heard which I assume were via double hop Sporadic-E but I guess you can never be too sure on 28 MHz. It's just possible some of the more southerly ones were via F2.
Two signals that stood out were LA5SJA way up in the north of Norway. I'd guess he must be in almost 24 hours of darkness at the moment. Also heard was R9XM deep into Russia.
Opening to N America on 28 MHz - Sat 11th Jan 2020
After a quiet start, 28 MHz on Saturday the 11th of January 2020 sprang into life from the late morning on with plenty of Sporadic-E signals on the band.
In total, I heard 247 stations in 30 countries. The unusual ones were ZS6NL in South Africa, LU8YD in Argentina and K1CA and W2VW in the USA. The American ones were interesting as it's unusual to get East-West propagation this far north during mid-Winter at the bottom of the Solar Cycle.
The Solar Flux was at 74 which is up a bit on recent weeks, sign of the next cycle starting?
The European stations heard on 28 MHz are shown below. The best thing about FT8 is that it really shows if a band is open or not. It seems as if there is some sort of Sporadic-E on 28 MHz on most days even throughout the winter.
In the days before FT8 when we only had cw beacons to listen to, that really wasn't so obvious. You could look at the text books and read that there is a Summer Sporadic-E season with a mid-Winter peak. It looks are if it never really dies away, even in the depths of Winter.
Saturday, January 11, 2020
Oblong Loops for 28 MHz and 50 MHz
What attracted my attention to it was the simplicity of the antenna and it has some notable features...
1) Ease of Construction... As you can see from the diagram on the left, the 50 MHz version is only 1-metre wide and the 28 MHz version is 1.8-metres wide.
It's not hard to imagine using a horizontal non-conductive support that wide and then effectively hanging the whole structure from something like a PVC mast or even the branch of a tree.
2) Simple 50 Ohm feed point... Most loops in the shape of squares or triangles seem to have an impedance around 100 ohms and require some sort of matching device.
This oblong loop seems to have a lower impedance and is closer to 50 ohms. As a result, it can be fed directly with 50 Ohm coaxial cable. It would however be probably worth making a few loops in the coax at the feed point to make a choke balun.
3) Cost... The antenna can be made with bits of PVC pipe and some wire. It should be very cheap to make.
If you want to get on say 50 MHz then this oblong antenna would be way better than some sort of commercial vertical covering 6m, 2m and 70cms. It should also be way better than some HF antenna like a G5RV or similar that it pressed into service. In terms of bang for buck, something like this is hard to beat. You'll need to get it up high though.
Have a look at VK3YE's video below and you'll get a better idea of what it's like.
Thursday, January 9, 2020
Opening to South Africa on 28 MHz - Thurs 9th Jan 2020
The one unusual signal was ZS6LKF from South Africa.
Txmtr Band Mode Distance Time (UTC)
IK4POI 10m FT8 1633 km 19:02:14
IK3BNO 10m FT8 1659 km 18:50:29
F1RAD 10m FT8 1273 km 17:52:14
IK4LZH 10m FT8 1665 km 17:40:49
S52EN 10m FT8 1803 km 15:23:18
G0FWX 10m FT8 435 km 13:39:15
LB6D 10m FT8 1444 km 12:55:59
LA5VSA 10m FT8 1386 km 12:24:15
OH1EDK 10m FT8 2107 km 12:22:59
OH6NEQ 10m FT8 2320 km 12:13:29
SM3SJN 10m FT8 1924 km 12:08:59
LA3BO 10m FT8 1479 km 12:05:14
LA7DHA 10m FT8 1496 km 12:02:29
OH7NO 10m FT8 2468 km 12:00:29
SM3LBN 10m FT8 1813 km 11:53:59
OH7TV 10m FT8 2479 km 11:41:59
LA9GSA 10m FT8 1499 km 11:36:44
LA5WJA 10m FT8 1609 km 11:27:14
OH1KH 10m FT8 2097 km 11:26:44
LA3DV 10m FT8 1433 km 11:26:14
LB2AG 10m FT8 1260 km 11:20:44
OH2ECG 10m FT8 2232 km 11:06:59
LA8EJ 10m FT8 1451 km 11:04:14
LA6JEA 10m FT8 1527 km 10:55:14
ZS6LKF 10m FT8 9336 km 10:42:44
GM1OXB 10m FT8 716 km 10:41:44
OH1TP 10m FT8 2103 km 10:39:59
OH1MRR 10m FT8 2103 km 10:16:59
EI3GRB 10m FT8 102 km 10:03:29
PA7EY 10m FT8 899 km 09:37:44
Wednesday, January 8, 2020
Sporadic-E on 28 MHz - Wed 8th Jan 2020
While Tuesday the 7th of January 2020 was pretty quiet on 28 MHz, the Sporadic-E propagation made a return on Wednesday the 8th of January with plenty of signals being heard on the band.
The only unusual signals were from southern Russia. These were either double hop Sporadic-E or possibly one hop F2.
According to PSKReporter, I uploaded 231 reports from 26 countries on 28 MHz on the 8th of January 2020.
The Solar Flux is at 72 which up a bit on recent weeks but is still very low.
Monday, January 6, 2020
Sporadic-E opening on 28 MHz - Mon 6th Jan 2020
There was a pretty good mid-Winter Sporadic-E opening on 28 MHz on Monday the 6th of January 2020. As can be seen from the map above, I heard plenty of PA stations from the Netherlands at about 1,000kms suggesting a reasonably high MUF. That seems to have been the case as others reported that 50 MHz was open as well.
There wasn't much in the way of DX but nice to see some activity on the band all the same, especially at the bottom of the sunspot cycle.
Saturday, January 4, 2020
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
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
Wednesday, January 1, 2020
Remarkable start to the New Year with a new 144 MHz tropo record from Cape Verde Is to Western Scotland
Back in September of 2018, G3SMT in the west of England managed to work D4Z on the Cape Verde Islands on 144 MHz to set a new IARU Region-1 tropo record of 4,431kms.
On the 28th of December 2019, Ian, GM3SEK worked D41CV from the same location on the Cape Verde Islands to extend the 144 MHz tropo record to 4,565kms.
On the 1st of January 2020, the New Year was hardly a few hours old when Calum, GM0EWX on the Isle of Skye in the west of Scotland managed to work D41CV on FT8 on 144 MHz. This now extends the IARU Region-1 tropo record to an amazing 4,776kms.
For the contact, GM0EWX was using an IC7100 with 400 watts into two 15-element long Yagi's about 15 metres above ground level.
Calum kindly sent on screenshots of the FT8 contact and they are added to the end of this post.
Mode of Propagation... It's very likely that the bulk of the path was due to a sea duct extending from the west coast of Africa, up past Portugal and up to the British and Irish Isles.
You'll notice however from the first map that the most northerly part of the path crosses over the island of Ireland. It seems likely that there may well be an elevated duct for this part of the path and it is then coupling into the sea duct for the remainder of the journey.
New limit... As the tropo record extends north, the number of potential stations capable of breaking it reduces.
The one intriguing possibility is a tropo path from the Cape Verde Islands up to the Faroe Islands, a distance in excess of 5,000kms. Is it possible?
Just how far is the new record?... As outlined in previous posts, it's fine to be quoting numbers for new records but sometimes you need a map to put things into perspective.
If the record was say east-west over the North Atlantic, a signal from St.Johns in Newfoundland, Canada would reach this far into Europe...
...and a signal from the south-west of Ireland would reach this far into North America...
Addendum... Here are some screenshots of the FT8 QSO courtesy of Calum, GM0EWX.
On the 28th of December 2019, Ian, GM3SEK worked D41CV from the same location on the Cape Verde Islands to extend the 144 MHz tropo record to 4,565kms.
On the 1st of January 2020, the New Year was hardly a few hours old when Calum, GM0EWX on the Isle of Skye in the west of Scotland managed to work D41CV on FT8 on 144 MHz. This now extends the IARU Region-1 tropo record to an amazing 4,776kms.
For the contact, GM0EWX was using an IC7100 with 400 watts into two 15-element long Yagi's about 15 metres above ground level.
Calum kindly sent on screenshots of the FT8 contact and they are added to the end of this post.
Mode of Propagation... It's very likely that the bulk of the path was due to a sea duct extending from the west coast of Africa, up past Portugal and up to the British and Irish Isles.
 |
| Tropo forecast from F5LEN - 03:00 UTC 01-01-2020 |
You'll notice however from the first map that the most northerly part of the path crosses over the island of Ireland. It seems likely that there may well be an elevated duct for this part of the path and it is then coupling into the sea duct for the remainder of the journey.
New limit... As the tropo record extends north, the number of potential stations capable of breaking it reduces.
The one intriguing possibility is a tropo path from the Cape Verde Islands up to the Faroe Islands, a distance in excess of 5,000kms. Is it possible?
Just how far is the new record?... As outlined in previous posts, it's fine to be quoting numbers for new records but sometimes you need a map to put things into perspective.
If the record was say east-west over the North Atlantic, a signal from St.Johns in Newfoundland, Canada would reach this far into Europe...
...and a signal from the south-west of Ireland would reach this far into North America...
Addendum... Here are some screenshots of the FT8 QSO courtesy of Calum, GM0EWX.
Tuesday, December 31, 2019
4,400km opening between Cape Verde Islands and the City of London on 144 MHz - 30th Dec 2019
On the afternoon and evening of Monday the 30th of December 2019, there was another amazing tropo opening on 144 MHz from the Cape Verde Islands off the west coast of Africa to the UK.
On previous occasions, the openings have been mostly confined to the western parts of the UK where there is almost a complete sea path to the Cape Verde Islands. On the 30th of December however, the opening was further east.
The map above and below shows the stations that heard the FT8 signals from D41CV or were heard by D41CV.
As you can see below, the opening seems to have been confined to a narrow corridor and had to cross over Brittany in France and the north-west part of Spain.
In a separate tropo opening a few months back, only the most westerly French station on the Brittany peninsula managed to work D41CV as they could just about clear the Spanish coast for a complete sea path. On the 30th of December however, more French stations got in on the action.
The most amazing reports however were those from around London. Up until the 28th of December 2019, the IARU Region-1 tropo record for 144 MHz stood at 4,431kms.
Now look at the map above. The distance from D41CV to the stations in London is...
G7LRQ (4,436kms), M0HRF & M0ICR (4,427 kms) and G7LXP (4,435kms).
In terms of making a two way contact, I believe G4DCV, G7LRQ and M0ICR were successful. Others may have been as well but I don't have any further info.
Now consider this. The distance from London to St.John's in Newfoundland, Canada is 3,735kms. The signal from Cape Verde Islands is an extra 1,000kms further.
It is really incredible that a signal a VHF signal at 144 MHz could travel 4,400+ kms from some islands off the west coast of Africa and get as far as the capital city of the UK.
Tropo ducting... The map below shows the tropo forecast from Pascal, F5LEN. As you can see, there is a maritime path from the west of Africa to the UK and Ireland.
Links...
1) F5LEN Tropo Forecasts
On previous occasions, the openings have been mostly confined to the western parts of the UK where there is almost a complete sea path to the Cape Verde Islands. On the 30th of December however, the opening was further east.
The map above and below shows the stations that heard the FT8 signals from D41CV or were heard by D41CV.
As you can see below, the opening seems to have been confined to a narrow corridor and had to cross over Brittany in France and the north-west part of Spain.
In a separate tropo opening a few months back, only the most westerly French station on the Brittany peninsula managed to work D41CV as they could just about clear the Spanish coast for a complete sea path. On the 30th of December however, more French stations got in on the action.
The most amazing reports however were those from around London. Up until the 28th of December 2019, the IARU Region-1 tropo record for 144 MHz stood at 4,431kms.
Now look at the map above. The distance from D41CV to the stations in London is...
G7LRQ (4,436kms), M0HRF & M0ICR (4,427 kms) and G7LXP (4,435kms).
In terms of making a two way contact, I believe G4DCV, G7LRQ and M0ICR were successful. Others may have been as well but I don't have any further info.
Now consider this. The distance from London to St.John's in Newfoundland, Canada is 3,735kms. The signal from Cape Verde Islands is an extra 1,000kms further.
It is really incredible that a signal a VHF signal at 144 MHz could travel 4,400+ kms from some islands off the west coast of Africa and get as far as the capital city of the UK.
Tropo ducting... The map below shows the tropo forecast from Pascal, F5LEN. As you can see, there is a maritime path from the west of Africa to the UK and Ireland.
Links...
1) F5LEN Tropo Forecasts
Monday, December 30, 2019
Conditions on 144 MHz - Sun 29th & Mon 30th Dec 2019
After a relatively quiet day on 28 MHz, I decided to listen for FT8 signals on 144 MHz for the 24 hours from 21:00 on Sunday the 29th of December to 21:00 on Monday the 30th of December 2019.
Using just an indoor Slim Jim vertical half-wave in the attic of my house, this is what I heard...
As you can see, there was some really good tropo conditions on the VHF bands with distances of just over 1,000kms being heard. Not bad for an internal antenna.
The best DX heard was EA1YV 1084kms, F1TRF 1073kms and DL6YBF 1066kms.
Using just an indoor Slim Jim vertical half-wave in the attic of my house, this is what I heard...
As you can see, there was some really good tropo conditions on the VHF bands with distances of just over 1,000kms being heard. Not bad for an internal antenna.
The best DX heard was EA1YV 1084kms, F1TRF 1073kms and DL6YBF 1066kms.
Saturday, December 28, 2019
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
Excellent end of year tropo opening results in new world record 432 MHz contact of 4562 kms
On some days, there are good openings on the VHF and UHF bands. Saturday the 28th of December 2019 was not only good, it was exceptional.
As outlined in a previous post, some record breaking signals from the Cape Verde Islands were heard in the UK and Ireland on Friday the 27th of December. On Saturday the 28th of December, those tropo conditions got even better.
The day got started with Mark, EI3KD working D41CV on FT8 on 432 MHz at 09:06 UTC for a new IARU Region-1 70cms record of 4,170 kms. Mark later went on to work the Cape Verde Islands on 432 MHz SSB.
Like on previous occasions, the record only lasted a few hours. At 11:09 UTC, Ian GM3SEK in the south-west of Scotland managed to work D41CV on FT8 on 432 MHz extending the record distance to an amazing 4,562 kms. GM3SEK was using 100 watts and a 23 element on 70cms.
It would seem as if this is not only a new IARU Region-1 70cms tropo record but also a new world record!
To put that into context, the red dot on the map below shows the limit of the old record of 3,284 kms which was between D44TS and CT1HBC back in July of 2014.
This is a screenshot of the FT8 contact between D41CV and GM3SEK on 432 MHz.
144 MHz... GM3SEK also worked D41CV on 144 MHz for a new IARU Region-1 tropo record. This is covered in a separate post HERE
More of propagation?... The tropo prediction map from Pascal, F5LEN is shown below. The key point to note is that the path between D41CV and GM3SEK is mostly over water.
It's probably unlikely that GM3SEK would have managed the contact if it was not for the fact that he is located on the northern edge of the Irish Sea between the UK and Ireland. Like on previous occasions, the most likely mode of propagation for most of the path was marine ducting with the UHF signal getting trapped in a layer above the surface of the ocean.
New record... Can it be broken? The map below shows the how far the new record distance reaches.
Considering that it's probably likely that a maritime path will be required, somewhere slightly further north in Scotland. Someone in the north-east of England might do it but it would require crossing a lot of the UK.
The one stand out location however is from the far western isles of Scotland.
4,562 kms.... Just how far is it? Sometimes it can be difficult to really appreciate just how far distances are, especially when the numbers get really high. I have prepared 3 maps which help illustrate just how far the new record is. And keep reminding yourself, this is 432 MHz!
If you put the transmitter on the south-west of Ireland, this is how far it would reach into North America...
If the transmitter was at St.Johns in Newfoundland, this is how far it would reach into Europe...
And for our Australian colleagues, this is how far the signal would reach if the transmitter was located on the north island of New Zealand...
Will the record be broken? ... I guess you should never say never but the potential number of stations to the north of GM3SEK seems to make it unlikely.
An amazing day for UHF radio and records.
Links...
1) F5LEN tropo propagation forecasts
As outlined in a previous post, some record breaking signals from the Cape Verde Islands were heard in the UK and Ireland on Friday the 27th of December. On Saturday the 28th of December, those tropo conditions got even better.
The day got started with Mark, EI3KD working D41CV on FT8 on 432 MHz at 09:06 UTC for a new IARU Region-1 70cms record of 4,170 kms. Mark later went on to work the Cape Verde Islands on 432 MHz SSB.
Like on previous occasions, the record only lasted a few hours. At 11:09 UTC, Ian GM3SEK in the south-west of Scotland managed to work D41CV on FT8 on 432 MHz extending the record distance to an amazing 4,562 kms. GM3SEK was using 100 watts and a 23 element on 70cms.
It would seem as if this is not only a new IARU Region-1 70cms tropo record but also a new world record!
To put that into context, the red dot on the map below shows the limit of the old record of 3,284 kms which was between D44TS and CT1HBC back in July of 2014.
This is a screenshot of the FT8 contact between D41CV and GM3SEK on 432 MHz.
144 MHz... GM3SEK also worked D41CV on 144 MHz for a new IARU Region-1 tropo record. This is covered in a separate post HERE
More of propagation?... The tropo prediction map from Pascal, F5LEN is shown below. The key point to note is that the path between D41CV and GM3SEK is mostly over water.
It's probably unlikely that GM3SEK would have managed the contact if it was not for the fact that he is located on the northern edge of the Irish Sea between the UK and Ireland. Like on previous occasions, the most likely mode of propagation for most of the path was marine ducting with the UHF signal getting trapped in a layer above the surface of the ocean.
New record... Can it be broken? The map below shows the how far the new record distance reaches.
Considering that it's probably likely that a maritime path will be required, somewhere slightly further north in Scotland. Someone in the north-east of England might do it but it would require crossing a lot of the UK.
The one stand out location however is from the far western isles of Scotland.
4,562 kms.... Just how far is it? Sometimes it can be difficult to really appreciate just how far distances are, especially when the numbers get really high. I have prepared 3 maps which help illustrate just how far the new record is. And keep reminding yourself, this is 432 MHz!
If you put the transmitter on the south-west of Ireland, this is how far it would reach into North America...
If the transmitter was at St.Johns in Newfoundland, this is how far it would reach into Europe...
And for our Australian colleagues, this is how far the signal would reach if the transmitter was located on the north island of New Zealand...
Will the record be broken? ... I guess you should never say never but the potential number of stations to the north of GM3SEK seems to make it unlikely.
An amazing day for UHF radio and records.
Links...
1) F5LEN tropo propagation forecasts
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