Saturday, January 11, 2020

Oblong Loops for 28 MHz and 50 MHz

Peter, VK3YE recently posted a video on YouTube about some oblong loop antennas 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

Thursday the 9th of January 2020 wasn't the best of days on 28 MHz. In the morning, there was an opening to the Nordic countries while there was a short opening to N Italy and Slovenia in the late afternoon.

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

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.

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

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.

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

Sporadic-E opening on 28 MHz - Sat 28th Dec 2019


There was some nice mid-Winter Sporadic-E on Saturday the 28th of December 2019 with an opening during the afternoon. The map above shows what I heard on 28 MHz so it would seem as if it mostly east-west.

I see from other reports that the 50 MHz and 70MHz bands were also open. It seems as if there was also a Sporadic-E opening at 144 MHz which is pretty amazing for the middle of the winter.

Cape Verde Islands heard on 144 MHz & 432 MHz in Europe over record distances

In a suprise end of year tropo opening, D41CV on the Cape Verde Islands off the west coast of Africa has been heard on 144 MHz and 432 MHz in the UK and Ireland.

144 MHz... On the 2m band, the FT8 signal from D41CV was heard as far inland as Staffordshire in central England. The signal was heard by G4KWQ in the locator square IO92AQ and the distance was an amazing 4,467 kms.


This is about 30kms further than the current tropo IARU Region-1 record of 4,436 kms which was set by D41CV and G3SMT in September of 2018.

While there was no new record set on the 27th of December 2019, it is surely only a matter of time before the current 144 MHz record is broken.

432 MHz... On 70cms, the reception report was probably even more impressive. On the evening of the 27th of December 2019, the 432 MHz FT8 signal from D41CV was heard by EI3KD on the south coast of Ireland.


The distance was 4,170 kms, an amazing distance for 432 MHz.

To put that into context, the current IARU Region-1 70cms tropo record is between D44TS on the Cape Verde Islands and CT1HBC in Portugal, a distance of 3,284 kms. The new reception report by EI3KD is about 900 kms further than the current record.

Again, it suggests that the current 70 cms record which was set back in 2014 is on borrowed time.

Tropo Forecast.... According to the tropo forecasts of Pascal F5LEN, there is potential for more openings from the British and Irish Isles down to Cape Verde Islands over the next few days. Any suitably equipped 2m and 70cms stations should avail of this opportunity and beam to the south-south-west.

Links...
1) Tropo forecasts by F5LEN

Thursday, December 26, 2019

ICOM radios down through the years...

ICOM recently posted this video on their YouTube channel showcasing some of the radios that they have released down through the years...

Monday, December 23, 2019

The Five-Metre Story ... Article from the Short Wave Magazine in 1949

After the Second World War, some radio amateurs in Europe were allowed to use the 5-metre band (58.5 MHz to 60.0 MHz) until 1949-1951 when this part of the VHF spectrum was cleared for TV transmissions.

The following article written by E.J. Williams (G2XC) appeared in the April 1949 issue of the Short Wave Magazine. It covers a period of time when radio amateurs in the UK were about to lose the band.

* * * * *

SHORT WAVE MAGAZINE - APRIL 1949

VHF BANDS
By E. J. WILLIAMS, B.Sc. (G2XC)
The Five -Metre Story- Summary of Results on Five-Metre Activity

To summarise the results obtained on Five Metres since the band was first operated, and the experience it has given all VHF workers in this country, is not the easiest of tasks-apart from which, we are all bidding farewell to an old friend. Operations on Five Metres find a unique and lasting place in the history of Amateur Radio in this country. In the amateur field, they made possible some remarkable developments in VHF technique ; every VHF operator, known or unknown, has benefited directly from the collective progress made by British amateurs on Five Metres ; and most operators cut their VHF teeth on the problems (which seem so easy now) posed by the Five Metre Band.

It will probably be agreed that the story of Five Metres divides itself into two well-marked periods. The first, the years up to about 1936, when self-excited transmitters and super regenerative receivers were the order of the day ; and the second, from 1938 onwards, when crystal control and either straight or superhet receivers became the standard equipment. The years between were a transition period when the need for stabilised apparatus was becoming generally recognised, with the DX possibilities of the band gradually assuming a greater importance.

Pre -War Era
For those who did not know the pre -crystal control period, we should like to paint a picture of five metres as it was then. The experience of your conductor started in 1933, but others knew the band long before that. That long distances might be covered on rare occasions had been proved by one or two reports of 100-mile (160kms) reception several years before, but in general, anything over 10 miles was considered DX and worth reporting. Transmitters were often of the push-pull tuned anode resonant grid type, feeding into long wire aerials.

Such was the transmitter at, for instance, G6NZ in Southsea. In common with other local enthusiasts, we built a super -regenerative receiver, but being on the opposite side of a 300-ft. hill from G6NZ, we failed to hear anything but ignition QRM. Nothing daunted, we persuaded a neighbour to spend Sunday mornings taking us round the district in his car, so that we could log G6NZ's signals in more favourable locations.

Other groups up and down the country were doing the same sort of thing. Portable work became the great thing. One Sunday in each month was set apart in the South of England as a 5-metre field day. Transceivers, each smaller than the last, were built by every- one and provided much fun, even if they did not add much to the sum total of radio knowledge. We remember a contact between G2XC and G6NZ while the latter was on a moving bus, and other similar novel contacts were made elsewhere.

In 1934, G6QB took his five -metre gear to the top of the Crystal Palace, while G5CV went aloft in an aircraft and obtained air-to- ground ranges of 130 miles (209 kms). G5BY went to the top of Snowdon, a venture repeated by G5CV, G6YQ, GW6AA and others later. Signals from Snowdon were heard as far away as Essex.

But by 1936, many of us were realising that so far we had only been playing at 5 metres and that if the full possibilities of the band were to be explored, both transmitters and receivers must be improved considerably. CW reception should be made possible, and that meant frequency stability at both Tx and Rx ends. Really good valves for use on 60 mc were still scarce and expensive, and in spite of the general acceptance that CC transmitters and straight or superhet receivers were desirable, progress was slow. Gradually, however, stabilised transmissions increased in number as news spread of the possibility of European DX ; commercial harmonics had been logged during the summer of 1936 and G2FA worked F8NW across the Channel, while G5BY (then at Croydon) was reported heard at W2HXD (trans-Atlantic).

But the first European QSO was delayed until July 2, 1938, when G5MQ worked I1IRA. About this same time, inter -G con- tacts over distances up to 100 miles (160 kms) or so were becoming commonplace, as a result of the improved Tx, Rx and aerials in use. In fact, we find A. J. Devon saying in the Short Wave Magazine for October, 1938, " 56 mc contacts are of little value as news items when the distances involved are less than 50 miles. (80 kms)" In the latter half of the same year, G5BY-G6FO obtained regular schedule contacts over the 126-mile (202 km) path between Croydon and Newport, Mon., for the first reliable ground -to -ground GDX, and G6FO also logged G6DH at 180 miles (290 kms). The G5BY-G6FO contacts stood for many months as the GDX record.

Early 1939 found G6DH striving to work ON4DJ across 85 miles of sea. And so came the summer, when in 8 days of June, G6CW made 13 contacts over 100 miles. Contacts between G and I were made on June 1, 13, 24 and 25, and G2ZV and G6CW set up a new inter -G record of 150 miles (240 kms). The Snowdon tests of that same summer were, however, not so successful as a result of a severe gale which reduced all the expectations of GW6AA and his helpers to nothing. In spite of that 25 stations were worked, including G6CW at 137 miles (220 kms). In August, 1939, the GDX record advanced another stage, when the late G2OD (Worthing) contacted GBKD (Sheffield) over a 190 -mile (306 km) path, while G2AO (Eastbourne) worked PAOPN. When, on the outbreak of war, activity ceased on September 3, 1939, not only had the GDX record been brought to a figure which would have been considered incredible only a few years previously, but contacts had been made between G and EI, F, I and PA.

Post -War Results
And so to 1946, when with the return of amateur licences the Five -Metre Band was one of the two bands made available, but shorn now of its LF end. With better and cheaper valves, and a general trend towards beams in place of long wires and simple dipoles, GDX was soon being worked. By June, A. J. Devon, in his feature "Five Metres" in the Magazine, was beginning to run out of superlatives ! G5BY made the first inter -European contact on May 19, working I1FA. About the same time G5MQ and G6VX were maintaining a 184 -mile schedule for 15 evenings in succession, while G5BY worked G5MQ on May 13 over a 215 -mile path. As A.J.D. said that month, "Inter -G working up to 200 miles is passing from the very uncommon and exciting". During June, the band opened to Europe on six occasions, G2XC, 5BD, 5BY, 5LL, 5MP and 6CW being there is take advantage of it. G5BY and G6LK started a regular schedule over 156 miles with remarkably consistent results. The GDX record passed to G5BY/ G8UZ. July 23, 1946, was an outstanding evening for inter -G work, while August 22 provided the best European evening of the year with the first HE contacts being made. Early October brought a fortnight of excellent conditions for GDX working, the evening of October 11 surpassing anything previously experienced. Complaints were coming in of congestion at the LF end of the band, and of weak, unindentifiable 'phones who failed to sign on CW.



In November came the first Short Wave Magazine Five -Metre Contest, lasting a fortnight. From the point of view of GDX, the event was a failure, conditions being far below normal, but all participants enjoyed it and activity was outstanding. G6VX (Hayes) was the easy winner of this Contest, with G5MA his runner up. There was a total entry of 44, and A. J. Devon estimated that about 300 G's were active on the band during the period.

G2WS/P in 1946


Aurora Openings
March 8, 1947, was the date of the first major Aurora opening on 58 mc, GDX signals being received from the North irrespective of great -circle directions and with fuzzy notes. During a further auroral display on April 17, G5MA (Ashstead) was logged by GM3BDA (Airdrie). In April, 1947, A.J.D., in the Magazine, Iaunched "Counties Worked" as a method of assessing collective progress, com- menting that there was known to be activity in 30 G counties. G5MA became first leader in the table with 22 counties worked. The EDX season opened on May 14 with the GM's receiving I's, while at G2XC we worked 21 counties in a month! The table of Five Metre Firsts was growing rapidly, and by the end of the summer 11 different European countries had been worked from the U.K. W5BSY/MM added to the excitement of that summer of 1947 by operating on 5 metres from the Mediterranean area, and a new GDX record was set up on June 1, 1947, over 285 miles (458 kms) between G5BY and G5GX.

Personality Note
In November, 1947, your present conductor took over from A. J. Devon, who for years had contributed this feature. As many may have guessed, it might now be disclosed that A.J.D. was the pseudonym of the Editor of the Short Wave Magazine.

Five metre news was temporarily eclipsed by the DX openings on 6 metres. A second Five -Metre Contest in January, 1948, attracted a good entry, although again we were unlucky with conditions. G6VX and G5MA repeated their former success and, as in the previous contest, occupied the first two places. The idea of the " Fiveband Club" was born on February 21, and was immediately well supported by VHF enthusiasts.

Rise-
Activity Week -Ends provided a valuable incentive during the summer of 1948. By a remarkable coincidence, all these week-ends produced unusually fine weather, and we were inundated with requests to make every weekend an "activity" one ! GM3OL and the Newcastle group broke through to the Midlands in May, and several new counties, notably Dorset, Somerset and Suffolk, appeared on the 5-metre map.

The Counties table now showed several stations at the 31 level. Excitement grew as in June GM3OL and G3BW were heard in the London area, and on June 13 a new GDX record was achieved by G3BLP and GM3OL, the distance being 296 miles (496 kms). On June 9 a tropospheric contact between G2XC and PAWL, 370 miles (595 kms), also set a new record. In fact, some 19 contacts during June of over, 200 miles (320 kms) via the troposphere were recorded in our columns. June 4 saw an excellent European opening, as many as eight different countries being heard.

With greatly increased activity in GI and GM the stage was well set for August 7, when an amazing spell of "aurora conditions" opened the band for working between Southern G and GM's and GI's. Record contact was that by G5MA and GM2DAU, a distance of 363 miles (584 kms). A further outcome of this occurrence was a rapid rise in the counties worked, G5WP reaching 41, and G6LK making his total 16 countries.

-And Fall
On September 1, 1948, the two -metre band became available for amateur use and from that date five -metre activity started on a steady decline. A contest organised by the R.E.F. on October 23-24 produced a brief burst of activity and enabled G3HWJA and G3CQC to make 460 -mile (740kms) contacts with F8YZ, thus raising the tropospheric record to an even higher figure. A second break in the general lull came as a result of our own Magazine VHF Contest in mid -November. This time conditions were excellent and numerous over-200-mile (320 kms) contacts were made, G5BY and G3HW/A being the outstanding stations.


To round it all off, we reproduce herewith the last set of Five -Metre Achievement Tables, based upon all the available information. Some of the figures are interesting : No less than 43 counties worked, 42 of them by a station in the South London area; nearly 100 stations figuring in the Counties Worked list, for which the qualifying standard is 14 counties ; 17 European countries worked by one station, followed by two operators with 15 countries each ; a total of 88 stations shown in the Countries Worked list ; 11 European countries worked first time on 58 me post-war, three of them-North Africa, Switzerland and Czechoslovakia-by the same operator ; an estimated total of not less than 600 G stations which have appeared on the band ; and some distance records which will stand as a monument to the operators who made them.

The detail of all this achievement, over a period of years, is contained in the pages of the Short Wave Magazine, which from the beginning has devoted much space, time and energy to the VHF bands. No other record can be so complete nor so accurate. It is with pride that we look upon their results in the VHF field and the vast accumulation of technical knowledge and experience gained by so many of our readers for still further VHF exploration. But unless they had taken the time and the trouble, not only to record their results but also to report them to us, this all - too -brief Summary would not have been possible, and much of the history of VHF achievement would have been lost. 

And so we come to the close of the story. Among the thoughts which pass through one's mind is the remarkably persistent attraction the band was held for so many operators. Many of the calls that were in the five-metre news in 1933 still hit the headlines in 1948. Among its regular habitués existed a unique spirit of friendly rivalry, an amazing willingness to help the other man, even to break one's own records.

From the technical point of view the Five - Metre Band laid the foundations of British VHF technique and provided a grand opportunity to investigate sporadic -E propagation ; the Summaries of European Activity and EDX contacts which we prepared from readers' reports have been acknowledged by research laboratories in several countries as a valuable contribution to the study of VHF propagation problems.


Most of the well-known 5-metre call -signs can now be heard on two metres-or if not there, then on 70 cms. The experience of Five - Metre operation enabled excellent two -metre records to be set up within a few months. On 70 cm. technique is somewhat different, but we have no doubt that the persistence and endeavour which brought success on "five" will prevail on 70 cm. as well and that in due course a story of great achievements will be written for this new band. Five has gone ! Here's to Two and Seventy ! 

British VHF Records 
58 mc (58 MHz)
GDX (Tropo), G3BLP/GM3OL, 296 miles (476 kms)
GDX (Aurora), G5MA/GM2DAU, 363 miles (584 kms)
Tropo (European), G3CQC/F8YZ, 460 miles (740 kms)

Saturday, December 21, 2019

Radio Netherlands TV documentary on 70 years of international broadcasting

Back in 1997, Radio Netherlands produced a TV documentary about the history of radio broadcasting on the short wave bands during the 20th century. The programme was put up on the Vimeo platform recently.

Anyone with an interest in short wave broadcasting might find it of interest...



Note that the video is 48 mins long.

Monday, December 16, 2019

Winter 2019 QRSS Compendium


QRSS is a CW mode in which the receiver bandwidth is drastically reduced and the rate at which code is sent is slowed beyond that which would be normally be readable by ear. A typical signal has a dot length of three seconds and a dot length of nine. The signal is 'decoded' by looking at the trace on a computer monitor rather than by ear.

There is a dedicated group called the QRSS Knights promoting the mode and are very active during the Summer months on 28 MHz.

Andy, G0FTD has compiled  a Winter 2019 Compendium and it can be viewed in PDF format HERE

Opening to Africa on 28 MHz - Sun 15th Dec 2019

The ARRL 10-metre contest was held last weekend and it usually generates quite a bit of activity if the band is in good shape.

On Saturday the 14th of December, conditions on the band were poor and I just heard a few stations on FT8 from around Europe. I scanned the CW and SSB portion of the band once and I heard just one very weak German station on CW.

I wasn't around on Sunday the 15th of December but I left the radio on monitoring the band. It seems as if the band was much better with plenty of Sporadic-E signals from Europe.


The really interesting signals are the ones from further away. For example, I heard Greece and Turkey... double hop Sporadic-E or F2 propagation?

In Africa, I heard TT8SN in Chad as well as three in South Africa. 3B8CW on Mauritius in the Indian Ocean was also heard.

Considering it's December and we're at the bottom of the sunspot cycle, it was a reasonable opening.

(Solar Flux: 71 / Sunspot number 0)

Sunday, December 15, 2019

Experiments continue on the 40 MHz band in the west of Ireland

Back in early 2018, the 40 MHz (8-metre) band was allocated to radio amateurs in Ireland (EI) on a secondary non-interference basis. Since then, interest in experimenting on the band has increased and there are now a number of EI stations carrying out tests.

The latest EI station on the band is Stefan, EI4KU in Co.Clare in the west of Ireland. Stefan has kindly forwarded on some details and photos of his latest tests.

Equipment... Stefan has built a small 1-watt beacon running on 40.013 MHz and is carrying out propagation tests. The photo below shows the home made beacon and the associated antenna tuning unit (ATU).


The beacon is using a crystal running at about 13 MHz and this is modulated by a varactor diode (FSK - Frequency Shift Keying). This is then tripled up to 40.013 MHz and is then buffered and amplified. The output transistor is a 2SC1970 running in Class-C with one watt after the low pass filter.

The signal is then fed into a home made Z-match ATU as shown below.


Unusually, 100-Ohm balanced coax cable is used on the output. This however provides a very good match to the antenna which is a single quad loop which would have an impedance of about 100 ohms.


The photo above shows the quad loop. The sides are about 2 metres each and it is shown being fed at the bottom so it is horizontally polarised.

This photo below shows the view to the north from Stefan's location so it looks as if he is in a good spot for VHF.


Stefan is currently in the process of building a transverter for the band. If anyone would like to carry out some tests on the 40 MHz, EI4KU can be contacted via QRZ.

Tests... In November of 2019, Stefan carried out some tests with Phil EI9KP and Michael EI3GYB in Co.Mayo with the equipment shown above and both heard the CW beacon.

EI4KP (IO52OW), EI9KP (IO54MB) & EI3GYB (IO53OT)

The distances covered were about 125 kms for EI9KP and 100 kms for EI3GYB.

The waterfall display below shows the slow cw signal as received by EI9KP in Mayo.


Interestingly, the signal over the 125 km path wasn't always steady. This second screenshot from EI9KP shows some multi-path distortion on the signal.


In an email, Phil EI9KP described it like this..."Screenshot attached showing reception of the beacon signal showing diffracted signal (wavey pattern). The signal diffraction is actually audible on the long carrier and it sounds like a wave building."

Phil also reports that he was using a horizontally polarised 2 element Yagi beam 5m above ground level for reception of the signal and it was RST 519.

EI3GYB... Michael, EI3GYB also reports that he heard Stefan's beacon from a distance of about 100 kms. Interestingly, Michael reports that there was a very slow fading on the band at times with the signal going from nothing up to 519. Most of the time, it was around 319 when the band was stable.

This mix of steady and fading signals would seem to concur with some of the reception reports that EI9KP experienced.

Michael doesn't have a dedicated antenna for the 8 metre band but instead was switching between a Sandpiper Moxon for 2/4/6 in horizontal position and a Windom antenna for 160 to 6 metres. According to Michael..."The Moxon was the best, although I had a period where I received nothing via the Moxon, but a 5/1 signal on the Windom."

It seems like that the 6m part of the Sandpiper Moxon was probably acting as a shortened dipole on 40 MHz so the gain would be somewhat reduced.

Michael also reports having several contacts with Phil, EI9KP on SSB who is 25 kms distant.

Thanks to Phil, EI9KP and Michael, EI3GYB for their reception reports... de EI7GL

Friday, December 13, 2019

Cambridge Consultants announce low cost DRM receiver design

DRM or Digital Radio Mondiale has long been touted as the digital solution for Medium Wave and Short Wave broadcast radio with higher efficiencies and less noise. There have been tests for well over a decade but very few adopters until now.

India now has 35 DRM transmitters covering the sub-continent with a potential audience of about a billion people. There is however still a serious issue regarding the high cost of receivers.

A company called Cambridge Consultants have now announced a prototype of a DRM design which will cost $10 or less. If they are successful, it could be a game changer for digital radio.

This is from their press release... "Cambridge Consultants has just held its annual Innovation Day, where we throw open our doors to industry leaders and reveal future technology. One of our highlights was the prototype of a DRM design that will cost ten dollars or less to produce, addressing that vital need for information by the 60-ish per cent of our global population that doesn’t have internet or TV. It’s low power, so can run from solar or wind-up.

This design will be ready in 2020, available for any radio manufacturer to licence and incorporate into its own products. "

More info HERE