Presentation on the DMR network in Ireland... by EI7IG & EI8JA

At the recent AGM of the Irish Radio Transmitters Society, John Ronan EI7IG and John McCarthy EI8JA made a presentation on the current state of the DMR digital radio network in Ireland and its brief history to date.

The slide show can be seen HERE. Use the Up & Down arrows to change the page and the Left & Right arrows to change the chapter.

FT8 on 28 MHz... Sun 13th May 2018

Another day with loads of activity on FT8 on 28 MHz. The map below shows what was heard in the 24 hours of the 13th of May 2018...

The 10 metre band opened in the morning and closed around 22:00 UTC. There was one short spell in the early afternoon where the band closed completely when there was no Sporadic-E propagation.

As can be seen from the map, there was plenty of signals from South America but not a whole lot going East-West. I suspect there would be a lot more spots from Africa if only there were stations active there.

The map below shows the activity from Europe. The most consistent signals all day were from the south to Spain and Portugal.

The Solar Flux was 69 today which is pretty low. Overall, I heard 445 different stations in 49 countries over the last 24 hours.

Presentation on the FT8 digital mode by EI5KO

At the recent IRTS AGM in Galway, Keith Wallace EI5KO made a presentation on the new FT8 digital mode which seems to be hugely popular at the moment. Following the AGM, Keith uploaded the slides to the IRTS Facebook page.

The problem with Facebook though is that anything more than a few days old is usually not seen anymore and of course, not everyone uses that platform.

I recently downloaded the Powerpoint slides and I found them to be a useful introduction to the mode. With Keith's permission, I have now put these up on Google Docs so that anyone can view them.

The link is HERE

FT8 on 28 MHz... Sat 12th May 2018

Another day listening to FT8 signals on 28 MHz and it was another busy one. Although it was similar to the previous days, it was different. The chart below shows what was heard during the 24 hours of Saturday the 12th of May 2018...

Nothing exotic from the east this time but it did open to North America! These signals from the south-east of the USA and one from Canada were heard around 14:00 to 15:00 UTC and were most likely multi-hop Sporadic-E. The ones from the USA were around the 6000km mark... three x 2,000km hops. The Canadian one was around 4,000kms... two 2,000 hops.

The South American signals were interesting. The ones from Brazil and Argentina were from the afternoon while the three signals from Chile were in the late evening.

The map below shows the signals here a bit closer to home...

Interesting signals from Mauritania and Western Sahara, both possibly double hop sporadic-e.

Sometimes it's the signals that are missing are the interesting one. No signals from Denmark or the south of Sweden today although I know there were stations active there.

Even though the maps might suggest that the band was wide open all day, it really wasn't. This is what was heard during the 17 hours or so that the band was open. At any one instant, the band was often open to just a small area but over the day, different signals appeared as the conditions changed.

Overall, I heard 519 stations today in 61 countries.

FT8 on 28 MHz... Fri 11th May 2018

Another interesting day listening to FT8 digital signals on the 28 MHz band. This is what I heard during the 24 hour period...

Signals from stations in China and Kazakhstan were heard at about 4:45 UTC which was dawn at my location. F2? Sp-E?

Several from South America including the Falkland Islands.

Cape Verde, Maderia and the Canaries in the Atlantic.

TR8CA in Gabon and the maritime mobile station off the coast of Angola again.

Again, plenty from Europe....

It still suprises me how many stations in the UK I can hear. They should normally be too close except for when the Sporadic-E conditions are pretty intense. As for today??? Direct Sporadic-E? Backscatter? Meteor or Aircraft scatter?

Interesting little group of stations out in Eastern Ukraine and in Russia. The band was also open to Germany at the same time so the eastern european signals were probably double hop Sporadic-E.

In total, I heard 387 different stations in 44 countries. Not as busy as the 10th of May but pretty good all the same.

FT8 on 28 MHz... Thurs 10th May 2018

I left the radio on 28 MHz all day today listening on the FT8 frequency. From what I could hear, the band seemed to be open from early morning until after midnight.

This is what was heard during the 24 hours of Thursday the 10th of May 2018...

Considering the solar flux levels are down at 70, it was pretty amazing what could be heard on 10 metres. Some of the notable signals heard were....

Five stations in Indonesia.
One in China as well as several in Kazakhstan and Uzbekistan.
One in South Africa and a maritime mobile station off the coast of Angola.
Brazil, Argentina and Chile in South America.
Two in Puerto Rico, two in the Dominican Republic and one in Dominica in the Caribeean.
And of course, plenty in Europe...

According to the PSK reporter website, I heard 865 stations in 59 countries in the last 24 hours.

It was interesting that because I was the only station in Ireland for most of the day, I was sometimes the only person hearing a distant station because of my westerly location.

At one stage, I had a look at the WSPR website. At that instant, there were 70 stations monitoring the 10 metre band on WSPR then where as there were 302 on FT8 at the same time. That's the thing that impresses me most about FT8, it seems to have the critical mass of people using it for it to be useful. I have noticed that on WSPR in the past, the band was obviously open to certain areas but there just wasn't anyone on from those locations.

Another advantage of just listening on this mode is that I don't actually have to be there. I was away from the radio for most of the day and the PC was doing all the work of decoding the signals and uploading the spots to the PSK reporter website.

This was only my second day listening on FT8 and I'd imagine I'll be using it now for the Summer for the Sporadic-E season.

New experimental digital gateway for Cork Harbour...

In order to facilitate testing of digital modes, Don EI8DJ has set up an experimental low power gateway at his home in Crosshaven in Cork Harbour. Please note that this will be on air only when Don is in the shack so it won't be on 24/7.

Some of the specs are as follows...

Frequency : Simplex on 438.700 MHz

Modes : DMR, DSTAR, Yaesu System Fusion and P25

DMR Settings : Colour Code 1, Time Slot 2.

Power : 5w into a Diamond X50 colinear.

Coverage is dependent on terrain but tests suggest that it is pretty good out to about 10kms and perhaps further to stations out to 20kms on higher ground. Radio coverage software suggests that it may be accessible from high ground on the north side of Cork City but the south side might be out of range.

As can be seen from the map, it is in an ideal location for radio amateurs on visiting cruise and passanger ships stopping off at Cobh and Ringaskiddy.

Click to see large version of Cork City north side coverage

If you have any questions about the gateway, Don can usually be found on the Cork repeater or on the Southern Ireland Repeater Network.

Traffic and signal levels heard on the EI8DJ gateway can be seen HERE

For more information on digital radio locally, have a look at the digital page on the Southern Ireland Repeater Network website.

FT8 on 28 MHz... Wed 9th May 2018

This morning, I noticed that the 28 MHz band was open but I couldn't hear one single CW beacon on the band. After hearing about the popularity of the latest digital mode FT8, I downloaded it and was listening on the band within an hour.

This is what I heard today on 28 MHz in Europe on FT8...

Most are about the right distance for Sporadic-E but there were a few suprises. The stations in the UK and Brittany were about the 500km mark...a bit short for Sporadic-E but not unknown. The ones in Bulgaria, Turkey and Russia are too long for one hop Sporadic and were probably multi-hop.

Outside of Europe, I heard these....

Like yesterday, I suspect that some Sporadic-E was helping out for the first hop to get down to lower latitudes where F2 propagation was possible. Still though, some interesting signals were heard. The one is Angola was a UW5EJX maritime mobile off the African coast.

In the 12 or so hours from 11:00 UTC to 22:00 UTC, I heard 104 different stations spread across 31 countries.

After just one day listening on the mode, I am very impressed at what I heard with a simple vertical antenna.

Links...
1) WSJT-X software suite
2) PSK reporter

French Guyana worked on 28 MHz...

Tues 8th May 2018... The Sporadic-E season is now well under way with plenty of signals being heard on the 10 metre band. On Tuesday the 8th of May, the band was open to part of Europe like Germany, Poland, Austria, Czech Republic, North Italy and Spain. As Sporadic-E signals go, it was nothing out of the ordinary with most around the 1200 to 2000km distance.

FY5KE... In the evening (16:45 UTC), there was an opening to South America which was interesting. I heard a station in Brazil on SSB and I worked FY5KE in French Guyana on CW with the first call.

Perhaps not the rarest of calls but interesting all the same. It's great to have the 10 metre vertical working properly again after repairing it last weekend.

The distance was 6600 kms which was pretty good. Almost certainly, the first hop from Ireland was via Sporadic-E out into the North Atlantic...maybe 1500kms or so... and the rest of the roughly 4000 kms was via other multiple hops.

Even though the Solar Flux is down around 70, F2 layer propagation might be possible from more southern latitudes like Spain, hence the need for the first Sp-E hop from Ireland.

Fishing buoy... I also came across a fishing buoy beacon on 28.420 MHz. This one was giving out a 5 second carrier followed by the letter 'D' (I think as it was very weak) and then would stay silent for 2m 25s. As far as I know, these are used to mark the location of fishing nets. Even though they are illegal, they seem to be pretty common and I would guess that this one was probably operating somewhere out in the Atlantic? The fact I heard it around the same time as the opening to South America would suggest this to be the case.

Repair of the CB Half-Wave antenna...

Back in November of 2016, I put up a CB half-wave vertical to use on 28 MHz. After being off air for four years, I just wanted to put up something cheap and easy to listen on the 10 metre band. I tuned it for 28.3 MHz and it tuned out to have a reasonable performance.

After being exposed to the weather for over a year, I found that when I tried to use it a few weeks back, it had gone intermittent and the VSWR was really high.

My initial suspicion was that water had got into one of the five telescopic sections that slide into each other resulting in poor contacts. I used a multimeter to measure the resistance between each section when the antenna was on the ground and it measured ok. I removed the waterproofing for the top telescopic section and on inspection, it was as clean as the day I put the antenna up.

One thing I then noticed was that the small screw at the base of the antenna looked slightly rusted. Using a Phillips screwdriver, I tightened this slightly and this fixed the problem! The VSWR returned to a nice low curve as it was before.

In hindsight, I probably should have waterproofed this screw from the elements but I'd guess that most people don't bother. It reminded me of a valuable lesson... be careful where there are two different types of metals touching.

In this case, a steel screw was making contact with aluminium ....a sure recipe for corrosion issues. I'll probably try to waterproof this over the next week.

Irish radio amateurs gain access to huge swathes of the VHF spectrum

The Irish Radio Transmitters Society announced today in their weekly news that Irish radio amateurs are to gain access to a huge part of the low band VHF spectrum.

EI stations will now have access to 30 to 49 MHz...all 19 MHz!!! The spectrum from 54 to 69.9 MHz has also been allocated... another 16 MHz! All of this is on a secondary basis and a 50 watt power limit.

Over the years, it's usual for the IRTS to lobby the licensing authority to get access to a small band here and there but not on this scale. I'm still assuming it isn't a mistake as the information on the Comreg website has been verified in the IRTS news. It may well be possible that it may in time become more defined as two distinct bands in the 40 MHz and 60 MHz region but for now, you can see the allocation as per the Comreg website shown above.

IRTS News...
Additional Frequencies
In December 2015 ComReg published a Draft Radio spectrum Management Strategy 2016-2018. The Society responded with a comprehensive submission to this draft and a summary of this was published in the March 2016 edition of Echo Ireland.

In June 2016 ComReg published its final Radio Spectrum Management Strategy 2016-2018 and indicated its intention to grant some additional spectrum to the amateur service. This has now been done and is in line with some of the requests made in the Society’s submission.

The 70 MHz band has been extended to 69.9 MHz to 70.5 MHz. This is an increase of 275kHz over the existing band of 70.125 to 70.450 MHz and is the full band that may be allocated to the amateur service under the European Common Allocations table.

Further spectrum covering all modes including digimodes has been granted on a secondary basis at 30 to 49 MHz and 54 to 69.9 MHz. The latter band also includes digital television in addition to all other modes. These new frequency bands are listed among the bands available generally to radio amateurs in Annex 1 of a recently revised version of the Amateur Station Licence Guidelines document ComReg 09/45 R4 which is available on the ComReg website.

The new bands in the 40 MHz and 60 MHz regions will, among other things, facilitate modern type beacons in the region of these frequencies as well as moving the existing 70MHz beacon on 70.130 MHz to the section of the band designated for beacons.

IRTS will be producing a local band plans for these two bands in consultation with countries that have allocations at these frequencies and IARU.

The Society would like to express its appreciation to ComReg for the release of this extensive spectrum to the amateur service on a secondary basis.

Source : IRTS News - 29th April 2018

Subsequent news item from the Royal Society of Great Britain (RSGB)..."In a landmark step, the Irish regulator Comreg has agreed to amateur access, on a secondary basis, to an extensive amount of VHF spectrum including 30-49MHz and 54-69.9MHz. In addition, their existing 4m band has been widened to the full 69.9-70.5 MHz CEPT range. It is expected that this will facilitate a number of innovative developments, including digital amateur television and new or realigned VHF propagation beacons. The RSGB congratulates its IRTS colleagues on their success, which dates back to a 2016 consultation input."

Germany to get 70 MHz allocation from 2nd May to 31st Aug 2018

I saw a news item recently that Germany is to get a temporary allocation on 70MHz again in 2018 from the 2nd of May to the 31st of August.

The allocation will be from 70.150 - 70.180 MHz. This does of course coincide with the Summer Sporadic-E season which will greatly increase the chance of making some contacts.

The suggested range for someone in central Germany is shown below....

The shortest skip distance is likely to be around the 1000 km mark and will probably require a very intense opening, possibly from mid May to early July.

The longest skip distance should be around the 2200 km mark. It's likely that the most common openings will be around the 1500 to 2000 km range.

If you live in Ireland, it might be handy to check for some useful markers. If you can hear Polish radio stations on 88-108 MHz, then check 70MHz to see if it is open to Germany. If you can hear Dutch or Belgian stations on 50 MHz, then check 70 MHz.

BBC report shows the impact of a sea path on Medium Wave signals

There has been a very interesting discussion on the Medium Wave Circle forum over the last few days about what kind of distances can be achieved over sea paths during daylight hours. Someone posted an interesting link to some tests that were done by the BBC back in 1936.

The BBC engineers used a 1kw transmitter at Start Point on a headland on the south coast of Devon to calculate the limit of acceptable signal strength which is shown above (extrapolated to a 100kw power level). They used a frequency around 1053kHz which has a wavelength of about 284 metres.

You'll notice how the signal struggles to penetrate inland yet can be easily heard along the south coast. As you can see, the signal strength at Hastings which is 307 kms / 191 miles to the east was the same as at Exeter which was over a land path and only 55 kms / 34 miles distant.

It really does show just how well ground wave signals on the Medium Wave band travel over sea water paths.

The BBC report can be seen HERE

Links...
1) Additional information about Start Point on the MB21 website HERE

Clare FM interview with organisers of the Wild Atlantic Way

There was an interesting interview recently on commercial radio station Clare FM with Simon Kenny EI7ALB and Alan Cronin EI8EM about the 2017 Atlantic Way promotion.

Long distance reception of a Spanish station on Medium Wave during daylight hours

Since I did a previous scan of the Medium Wave band in March, I have found several other very weak signals buried in the noise. One of these however is just about audible and can be heard in the middle of the day. I built a very basic loop aerial with some wire would around a cardboard box (30 x 45 cms) and tuned it with a variable capacitor. The result was that I can now ID two of the signals.

The signal on 855 kHz was Radio Nacional 50kw transmitter near Santander on the north coast of Spain, a distance of 992 kms or 616 miles. As can be seen from the map above, the path is almost completely over the ocean.

The aerial mast in Spain is just 300m or so from the water while I am 10 kms from the south coast of Ireland.

Radio mast near Santander

The other signal heard was from the test DRM transmitter of France Blue (8kw) on 1071 kHz near Brest, a distance of 500 kms or 310 miles.

I was wondering if the signals were possibly sky wave but I don't think so. They are there in the middle of the day every day and they are really steady like you might expect from a ground wave signal.

The radio used was a very basic Sony radio which was indoors. The loop aerial was just sitting on top of it.

992 kms seems like a remarkable distance for a ground wave signal on the medium band. There are plenty of much closer transmitters in the UK that I can't hear but the sea path to Spain seems to be making all the difference.

Night time scan of the Medium Wave band during April 2018

Following on from the day time scan of the Medium Wave band that I did back in March 2018, I have spent the last four weeks listening to the band at night. As before, I was using basic domestic radios at my house near Cork City on the south coast of Ireland.

I used the Silvercrest above which is a very basic and not so sensitive receiver to find a signal using the digital frequency readout. I would then use the more sensitive analogue Sony radio below to listen to the signal properly so I could identify it.

All of the signals were heard roughly 2-4 hours after sunset... approx 9pm to 1am local time. As you might expect, a lot more signals were heard during the hours of darkness and the full list is shown at the bottom of the page.

Some stats and figures....

a) Spain...A total of 109 different signals were heard and roughly 50% of those were from Spain. With the sea path to the south from Ireland, it was probably no suprise that the Spanish signals were so strong and numerous on the band.

b) Gaps....Tuning from 531 kHz to 1602 kHz, there were 35 channels where no signal was heard. It's not that there was no signal there, it's just that I couldn't hear one. In some cases, very strong signals tended to block out the adjacent channels.

c) Countries......The countries with the highest number of stations heard were Spain and the UK. The only signal heard from Eastern Europe was Radio Free Europe in Lithuania.

Italy...Some stations in the north-west of the country were heard at about 1400kms.
Algeria & Tunisia....Some high power stations were heard here along the north African coast at roughly 2000kms.
Portugal...Not too many from there.
France....Two signals....a monster 1 megawatt transmitter in the south east (~1500kms) and a digital DRM (Digital Radio Mondiale) transmitter from a site near Brest in Brittany (~500kms). The DRM signal could be heard as a hissing signal with no obvious pattern.

Belgium and the Netherlands...Not too many from there.

UK...The UK signals were by far the most interesting ones to hear. Many were buried in the noise and were only identified by listening to a particular song and then checking online to see what they were playing. I found that the online feeds were often 20-30 seconds behind the live radio signal.

Strong English Stations.....In terms of strong signals that could be listened to at night, these were the strong ones....
810 BBC Radio Scotland Westerglen??
882 BBC Radio Wales 100 Washford, Somerset, England
909 BBC Radio 5 Live 50 Clevedon, Somerset
1053 TalkSport 500 Droitwich, SW of Birmingham
1089 Talk Sport 2 Washford
1215 Absolute Radio 100 Washford, Somerset, England
1341 BBC Radio Ulster 100 Lisnagarvey, Belfast
1368 Manx Radio 20 Isle of Man

These were what I would call acceptable quality. Most of the others had too much interference with them to really listen to. I found it interesting in how on a band full of signals, I could only find seven English speaking stations that were worth listening to at night.

Interference...This biggest issue when trying to listen to some of the UK stations was the level of noise and interference. In many cases, there was a strong Spanish station on the same frequency and it was a case of rotating the radio and nulling out the Spanish station using the directional properties of the internal ferrite rod aerial. On one occasion, I could hear a Spanish station perfectly clear, I'd rotate the radio by 90 degrees and there was a perfectly clear English station on the same frequency.

Echo......Some of the UK and Spanish stations are using the same frequency multiple times in their respective countries. It probably sounds fine in the targeted service area but outside the service area, it results in a loud echo which makes it difficult to listen to.

2 second echo......This was an interesting one. There are two Smooth Radio transmitters listed on 1557 kHz.

1557 Smooth Radio 0.76 Northampton
1557 Smooth Radio 0.5 Southampton

It was impossible to identify which one I was hearing until I realised that I was actually hearing both of them with a two second delay between them! I'm not sure which one was first but I was certainly hearing both of them.

In conclusion...... It was interesting to do a detailed scan of the medium wave band to get a feel for what it is like currently. It is something I would have done many many years ago when I first started listening on radio.

What's pretty obvious is that a lot of stations in Central and Eastern Europe have now closed down their medium wave transmitters and have moved to VHF and digital. Looking at the various frequency listings and from my own observations, Spain and the UK are the two main countries in Europe that still use the medium wave band in a big way.

In the past, I would have listened to the band using a long wire aerial... great for bringing in the weak signals but it can't discriminate between stations. With so many Spanish stations on the band, it is really important to have a directional aerial so that some stations can be nulled out.

I was also suprised as to just how well the internal ferrite rod aerial in the Sony radio performed as it pulled in some of the lower power stations in the UK, especially the ones under 1kw. Prior to this, I would have assumed that I would need a long wire to pull in the low power ones but that doesn't seem to be the case.

The full list of station heard is below...

Low Pass Filter for the 10m & 11m Bands

Another one from the archives :o). This is a design for a low pass filter for 29 MHz and would be suitable for anyone on the 28 MHz or 27 MHz bands who needs a filter to reduce harmonics. This is especially valid for anyone using a low powered radio to drive an external amplifier. e.g. Amplifying  4w to say 50-100w.

Coils...12 SWG wire. 6 turns. 8mm internal diameter. Coil length 19mm.

Capacitors...High Voltage ceramic or Mica. 110pf Cap is 100pf and 10pf in parallel.

A suitable enclosure might be a diecast box with the filter built on copper clad board. Note the screen which can be made from the pcb material as well. If you can live with a slightly lower performance in terms of filtering, you can omit the internal screens but make sure you put it in a metal box.

Hands free morse code contact :o)

This is a great video! Italian radio amateur Mauri IZ5OVP makes contact with C31CT in Andorra...but without a morse key! :o))



For those of you who can't read morse, it goes...

IZ5OVP gives his call sign IZ5OVP in morse
C31CT replies with IZ5OVP IZ5OVP 599
IZ5OVP replies with R R 599 BK
C31CT concludes the contact with R TU

molto bene

A quick look at network radios...

What is radio? As time goes by, the fine line between what can be called 'radio' and what is the internet is becoming increasing blurred.

I was on the 70cms band today using the Echolink gateway about 10 miles to the north in Watergrasshill and I spoke to Brian GM7JDS in Scotland who was using an Inrico TM-7...a so called 'Network Radio'.

A network radio is essentially a mobile phone that is made to look and behave like a radio. It can have the same appearance and some like the Inrico TM-7 have a traditional microphone which might be found on a mobile rig. It uses the Android operating system, behaves like any smartphone and can be used through wi-fi as well.

But is it 'radio' as opposed to 'a radio'? Is it 'radio' if someone at the other end is actually using a real radio with RF going out over the airwaves? What if someone is using say a DMR radio into a local hotspot in their own house, is that any more 'real radio' than this?

At first glance, a network radio isn't a radio... or at least not a traditional radio. But if it allows you access to various repeaters around the world, is it not just a remote access for a radio? If it looks like a radio and behaves like a radio, is it a radio? Many people will have different opinions.

Some of the purists may well dismiss this as not real radio but it could be the perfect solution for someone with antenna restrictions or living in an apartment complex.

From my own point of view, anything that results in some activity on an amateur band somewhere can only be a positive thing.

There is an explanation on network radios below...

Proposal to establish EI VHF Activity Nights

Proposal : Establish EI VHF Activity Nights

17th March 2018 : At present, the activity level on the VHF and UHF amateur bands is very low, possibly the lowest ever. It doesn’t help matters when the few radio amateurs that are active are spread across different bands and modes and are on air at different times.

The suggestion is that VHF activity nights should be established on Tuesday evenings. The RSGB hold VHF/UHF contests on certain Tuesday nights and the proposed schedule would tie in with those.

The schedule would be as follows...

First Tues of the month... 2m (Aligns with the UK)
Second Tues of the month... 70cms (Aligns with the UK)
Third Tues of the month... 6m & 4m
Fourth Tues of the month... Digital - Fusion / DMR / D-Star

Each activity period would be from 7 to 10pm. It's up to individuals to do what they want to do. SSB / FM simplex / repeaters. Local rag chew or try to see how far they can get.

The plan is to start it in Cork in April of 2018 and to try to encourage other areas to take part as well. I have asked the IRTS VHF manager to help publicise it on their website and newsletter.

Update : 3rd May 2018... The banner for the activity night is now up on the IRTS website.