VIDEO: Beginners guide to digital voice modes (D-STAR, DMR & FUSION) ...by Tim, GW4VXE

As part of the RSGB Tonight at 8 video series, Tim GW4VXE gave an interesting presentation on digital voice modes like D-Star, DMR & Fusion. This is really aimed at beginners or anyone who is not familiar with these modes.

The video is shown below. The presentation lasts from about 06:00 to 1:09:30 and there is a Q&A session after it which lasts until 1:43:40.

Digital Radio Operating Manual - Sept 2021... by Steve Wright, EI5DD

Steve Wright, EI5DD has now updated his comprehensive manual for anyone in Ireland with an interest in the DMR, C4FM and D-Star digital modes. The 62-page document  is a substantial increase on the 44-page 2020 edition and should be of interest to anyone starting off and even to established users who want to get a better understanding of the various digital systems.

While the guide is primarily aimed at radio amateurs in Ireland, a lot of the material covered should be of interest to radio amateurs in other countries as well.

The online manual can be seen HERE

Buzzing interference on a digital DMR signal

 

On the 4th Tuesday of every month, we hold a local digital net here in Cork and this weeks net was on the DMR Talk Group 2723.

During the net, it was noted that Robby EI3GGB had quite a loud buzzing noise on his audio. His voice blocked out the buzzing/hum but the sound was very noticeable in between his words.

Rob was using a TYT MD-380 handheld with a magmount antenna on 70cms.

The buzzing sound sounded very much like mains hum, as if he was using a battery charger at the same time as when he was transmitting. He tried switching from the mains power supply to just a battery pack on its own but to no avail.

Through a process of elimination, we eventually traced the problem back to an external speaker mike.

It would seem that the problem is the RF signal on transmit is getting into the speaker mike and causing interference. We don't know yet whether the RF is getting into the electronics in the microphone or via the lead and into the radio.

Robby bought the 'Kenwood' speaker from China but it's not clear whether it's the real deal or just a clone. Hopefully the RF interference can be cured by using a simple clip on split ferrite core which Robby is going to source.

If you are using DMR and people start saying that your audio is distorted, noisy or buzzing then try removing the speaker mike if you have one.

New DMR repeater EI7FXD now operational in Cork - Dec 2020

The good news radio wise locally is that a new DMR repeater on 70 cms is now on air near Cork City in Ireland. It is co-sited with the existing EI7FXR analogue FM repeater at Farmers Cross near Cork Airport.

The callsign of the new digital repeater is EI7FXD and it has an output frequency on 430.250 MHz The input is 9 MHz higher on 439.250 MHz. This configuration is usually designated as DVU-R20.

The colour code is 1.

The Brandmeister ID of the repeater is 272015 should anyone wish to monitor the Brandmeister dashboard and hoseline.

Info from the Southern Ireland Repeater Group - DMR repeater for Cork City

A new 70cms DMR repeater was installed at Farmer's Cross near Cork city on Monday December 21st to provide DMR coverage to Cork City and surrounding areas. The set up consists of a Motorola DR-3000 repeater and the antenna is a CAT-C440 @ approx 50ft. It's the fourth digital repeater set up by the Southern Ireland Repeater Group and will complement our other three digital installations located at West Waterford, Waterford City and Mt. Leinster.

EI DMR registrations at the end of Q3 2020

 

The above chart shows the number of DMR (Digital Mobile Radio) registrations by EI stations for every quarter up to the end of Q3 2020. The first DMR numbers were issued in 2015 and this peaked with a surge of interest in 2017. After that, the number of registrations per year slowed and dropped by about 30% to a lower level.

It now looks as if 2020 has seen a rebound in the registration numbers with the numbers at the end of Q3 2020 already ahead of the total for 2019.

The first quarter of 2020 had 19 new registrations but 10 of these were for club call signs which will probably never be used. The second and third quarters were for individuals and show a renewed growth in interest and numbers. Even if the club calls are removed, it looks likely that 2020 will end up as the second highest year yet in terms of new DMR registrations.

As of the end of Q3 2020, a total of 229 DMR numbers were issued for EI calls. If the club calls and duplicates are removed then 192 individual EI stations have DMR numbers.

Digital Radio Operating Manual... by Steve Wright, EI5DD

Steve Wright, EI5DD has now compiled a comprehensive manual for anyone in Ireland with an interest in the DMR, C4FM and D-Star digital modes. The 44-page document should be of interest to anyone starting off and even to established users who want to get a better understanding of the various digital systems.

While the guide is primarily aimed at radio amateurs in Ireland, a lot of the material covered should be of interest to interested parties in other countries as well.

The online manual can be seen HERE

Info about EI7FXD - the new DMR repeater in Cork on 70 cms

As outlined in a previous post, a new DMR repeater on 70 cms should be on air near Cork City in the next few week. It will be co-sited with the existing EI7FXR analogue FM repeater at Farmers Cross near Cork Airport.

COMREG has issued a licence call EI7FXD for the new DMR repeater with an output frequency on 430.250 MHz The input is 9 MHz higher on 439.250 MHz. This configuration is usually designated as DVU-R20.

The colour code will be 1.

The Brandmeister ID of the repeater will be 272015 should anyone wish to monitor the Brandmeister dashboard and hoseline, when it becomes active.

EI7FXD Coverage... The map below shows the approximate coverage out to about 60 kms.

A lot of the more distant coverage in Green is just the tops of hills so it's probably more appropriate to look at the close in coverage.

Some points...

• The Farmers Cross site overlooks Cork City so there should be saturation coverage there. Anyone with a DMR handheld should be able to access it.
• Anywhere in the shadow of hills is likely to have problems on 70cms. e.g Blarney, Inishannon, Bandon, Mallow, Fermoy, Glanmire & Passage West.
• The coverage on the N25 to the east should be good as far as the Youghal by-pass. After that, there is coverage from the Clashmore repeater EI7CDD.
• Coverage on the M8 motorway to Dublin is good until Watergrasshill. Once you crest the hill, coverage may be a problem.
• The same applies on the N20 north to Mallow. Coverage ends just north of Rathduff.
• On the N22 to the west, there should be good coverage until Lissarda. After that, screening from hills will be an issue.

It is expected that the new repeater will be on air before the end of 2020.

Video on the Galway Digital Radio Network by Steve Wright, EI5DD

A recent video presentation by Steve Wright, EI5DD on the principles of DRM radio and the network in Ireland is shown below ........

If anyone in Ireland is interested in getting going on digital radio then it's worth watching to get a basic understanding of what's involved.

EchoLink now connected to Irish DMR Network

The Irish digital radio community continues to grow with more stations registering for DMR numbers every month. New digital repeaters and gateways have been established around Ireland to allow various users talk to each other.

One of the latest improvements to be made to the DMR network has been the establishment of a link to the Echolink network by John Anderson MI0AAZ. Anyone connecting to MI0AAZ-L under LINKS on the Echolink network will now connect to Talk Group 2724 on the Irish DMR network.

It will also connect at the same time to Yaesu Fusion Wires-X room  CQ-IRL  no 41411,  YSF independent fusion network no 04251 and the Allstar network no 29884.

This is an excellent way for those who are unsure about digital radio to connect to users on the DMR network so that they can ask questions and to see what the audio sounds like.

Additional info...
There are currently three Talk Group channels on the Irish DMR network with  multi bridging capability to other digital voice systems.

DMR TG 2724 links to the following:
Allstar node 29884
Fusion C4FM  YSF node 04251
Fusion C4FM Wires-x node 41411
Echolink node 883269

DMR TG 27247 links to the following:
DSTAR XRF925D
Fusion C4FM Wires-x 41280 & 41619
Fusion C4FM FCS 00430

DMR TG 27248 links to the following:
Allstar node 47137
DSTAR XRF925C
Fusion C4FM FCS 00480

Credits : Thanks to John MI0AAZ and Don EI8DJ for the above info.

Guest post : The Galway DMR Repeater by EI5DD

The following article was written by Steve Wright EI5DD and outlines the progress being made in establishing a new DMR repeater in Galway in the west of Ireland.

The Galway DMR Repeater... by Steve Wright, EI5DD (Sept 2018)

After deliberation, it was decided that a good quality Commercial DMR Repeater should be acquired for Galway. It is easy to suggest that ex commercial DMR mobiles could be converted and lashed together with homebrew components but at the end of the day there is nothing to beat the reliability of an item that was purpose and virtually operator proof.

Consideration was given to ex-commercial Motorola Repeaters, but they still retain their value despite long hours of service and being a well-used second-hand model. It should be noted that Waterford have a plentiful supply of these repeaters and have two in service at present but there was a slight reluctance to sell one off to the “Galway Lads” as they would surely have a good use for every item further down the road considering the prolific Southern Ireland Repeater Network currently expanding. There are, in fact, plans to place a third Digital repeater on Mount Leinster by 2019.

The Galway Repeater and Gateway ready for the New Site

The decision to go with Hytera was prompted by John, MI0AAZ, who had a little used Hytera RD 985 UHF repeater for a reasonable price. This Repeater was capable of running 50 watts maximum although it would be more prudent to run it at 40 watts. The repeater had built in cavity filters capable of handling the power passed through them. Aengus, EI4ABB, kindly tuned them without difficulty, and had them ready within the day. The code plug was relatively easy to compile and probably the harder part was ensuring that the internet connection was correct set up within. Unfortunately, to get the internet information correct required adjustment of settings within the wireless router. By working between the two systems it was possible to secure a trouble-free connection. Connection to the Repeater was made to the router by Ethernet cable.

Inside the Hytera

As the 2 metres Digital Gateway is to be co-sited, the same procedure was required for the connection of the Gateway to the Internet. Not an easy task but it all came together with the purchase of the correct router.

Fortunately, an ABS case had been purchased from Arthur, EI7GMB, some time ago. It was a perfect housing for Repeater, Gateway, Pi-Star controller and Power Supply. Everything was securely housed with a cooling fan installed below the GM350 Gateway Radio. Time to apply the power. Everything sprang into life and went through its boot-up process. Connectivity through the internet was perfect and it was possible to adjust parameters on the Gateway via remote access. Once Set-up, the Repeater settings can not be altered remotely unless there is a computer attached. There would never be a need to do so at the best of times although a means of cutting the power and restarting would be necessary should a hang up occur. Unlikely, but possible. To this end a remote access GSM controller was added to cover this eventuality and also a necessary addition to shut down the Repeater at the whim of ComReg should the eventuality arise. All systems were in perfect working order and the soak test began.

The Galway Multi-mode Gateway

After running solidly for one month, the repeater has run trouble free. There is no de-sense on the receive side. Signals passed through have exhibited no distortion and the Bit Error Rates (BER) are zero. Obviously, there are limitations in coverage from the EI5DD QTH but it does give opportunities to observe the effects of reflections or weak signals. Around this time Mark, EI6GUB, obtained a DMR set and has given the Repeater and Gateway plenty of activity. His activity was not confined to Galway, or Ireland, but reached out to England and Scotland where plenty of QSOs were made. In the background it was possible to determine the reliability of communications through the Repeater and Gateway systems.

The Repeater and gateway are now be considered ready for their new site where an excellent service typical of this high spot can be expected. Better still, the Western side of Galway along the Spiddal Road will be enhanced as well as operation from the Aran Islands. Loughrea and Tuam should receive good signals and the roads along the opposite side of the Bay and around the Burren will also benefit.

Where do we go from here? Following the IRTS AGM we had enough to procure a second Repeater. An offer of a second, brand new Hytera RD 985 was snapped up to complete the system. It would be proposed that this be located on a high spot in the middle of Galway or, wherever is most effective, where it would be able to cover huge footprint of the county and perhaps neighbouring counties. As the footprint of the Galway Repeater would overlap with the proposed Repeater, it should be possible to “Roam” between the two much like a cellular phone. This would provide seamless communication whilst driving over distance.

Practicality suggests that there would be minimal fuss installing this Repeater as the operating parameters have already been defined. It would only require a power supply, connection to the internet and appropriate filters, and an antenna to get it on the air. This process should be painless considering the ground work done on our other two systems.

Those on trips abroad will be guaranteed communication back into Galway as will those who have relocated. Operators driving through the Galway area will be given an excellent service as will those resident in the City and County. Of course, it will rely on a little co-operation from our own operators in the form of a welcoming QSO from time to time.  Even if the Galway operator appearances are few and far between, there will always be a wealth of activity within the network that may be operated by the press of the PTT via a User Activated Talk Group. Never a moment where it is not possible to connect another DMR operator anywhere in the world.

In conclusion, it the facilities in Galway would be second to none in the digital world. DMR is obviously a proven technology governed by the ETSI standard. It works well for commercials and has “done what it says on the tin”. Judging by the equipment in use, the Hytera RD 985 is reliable and will be trouble free so there will be little need for maintenance. Additionally, the 2m Digital Gateway complements the system and gives the VHF operators another entry into the system. Obviously, there may be firmware upgrades from time to time but his again should pose no problem and would be brief. You are all cordially invited to enjoy and participate this rapidly developing network.

The Server 
It was through Steve, EI5DD, and John MI0AAZ, and Dave Randles, M0AUT, that the possibility of the Brandmeister Server for Ireland was negotiated through the Brandmeister management team in Holland. Having secured the go ahead, the next job was to find a home for it. John Ronan kindly consented to establishing it in his IT section located in the Waterford Institute of Technology. The system was established in the Waterford IT in March 2016. Following a running in period, and more familiarity with the system, the Server went live in May 2016. The criteria for operation was to have a minimum of 10 repeaters linked in – we only had 3, 2 Gateways and a number of personal hotspots. Within the year, we have a migration of Scottish Repeaters and several UK repeaters resulting in 20! The migration was down to the fact that the server was running perfectly with minimal down time save for the occasional Firmware and Software updates not to mention that the Sysop was approachable.

The system has been trouble-free to date and well managed/maintained by John Ronan, EI7IG. By comparison, the UK has had numerous outages. It really is a credit to Ireland. It is a vital requirement to have somebody with the knowledge and dedication running such a system.
Waterford

Waterford have made huge progress with the establishment of two multi-mode Digital Repeaters and propose a third on Mount Leinster in 2019. Such enthusiasm has encouraged many operators to participate in Digital Radio in Cork and Waterford and surrounding areas. John McCarthy, EI8JA, has spent much of his time building and setting up the Digital Repeaters in his area alongside his commitment to the Southern Ireland Analog Repeater Network. The dedication exhibited by John Ronan, EI7IG, has made it possible to connect these projects together and to the rest of the world.
The DMR network will expand and it will probably be down to the efforts of the Southern Ireland Repeater Network. Galway can do little more at this time. It is going to be well served and can only rely on the continuity from other areas such as Mayo or in directions along the Dublin road from neighbouring counties.

Mayo has a Digital Gateway running both DMR and Fusion and this provides a fine link into the system. It has been running for the last year and results are good from it. It does, however, share the antennas for EI3IX’s

Other parts of the country have long standing plans that have not developed much further than discussion. Ronnie, who would have been in a great position, had he made progress at the time. Hopefully his efforts will bear fruit soon. Ronnie did have plans for the Dublin area as well and that would probably encourage an interest from an area well populated with amateurs. Mullingar has a DMR Repeater License but nothing built or active to date. Rumour has it that Dundalk has plans but nothing actually written in stone as yet.

Limerick has fusion but has never exploited its networking capabilities making Fusion a bit of a “dead Duck”. The repeater does, however cover a good area and /M Fusion is possible which is a plus point. A shame that Limerick operators seldom communicate outside of their own group.  Donegal’s fusion project is not really a player as such as it is tucked away giving little coverage here in the southern parts of the world.

The Galway Repeater will eventually see a high location and combined with its wires-X should provide an excellent service. This will give everybody an opportunity to network via Wires-X but all is not lost, as Fusion can be accessed via Talk Group 2724 on DMR.

Links...
1) EI5DD website
2) Galway VHF Group

DMR registrations in Ireland at the end of Sept 2018

The number of EI stations registering for Digital Mobile Radio numbers continues to grow with an average of 12 per quarter so far in 2018. The chart below shows that 136 DMR numbers had been allocated as of the end of September 2018.

Out of those 136 numbers, 5 were clubs and 12 EI calls had two numbers so the total number is something like 119 individuals.

Looking at the island of Ireland overall, it is perhaps a little suprising to see how many DMR numbers are allocated in Northern Ireland by comparison.

The 410 from Northern Ireland can be broken down as follows...
GI* = 138
MI* = 213
2I* = 59

Buried in those figures are full, novice and foundation licences. Some may have two numbers and some may have upgraded from a foundation to a novice call in the last three years. If we use the EI numbers as a guide then that 410 in the north could actually mean something like 350 individuals.

That gives a ball park figure of about 470 individuals with DMR numbers on the island of Ireland.

The big difference in numbers between Northern Ireland the the Republic may possibly be accounted for by the following reasons...

1) One year ahead... Digital Radio and DMR started in Northern Ireland about a year ahead of the rest of the island. The big surge in numbers in EI in the first two months of 2017 mirror a similar surge in GI a year earlier.

2) Licence for beginners... It's a lot easier to get a licence in the north of Ireland with the option of a foundation and novice licence. In the Republic, the only option is to sit a test and get the full licence.

Links...
1) http://ham-digital.org/dmr-userreg.php

DMR net planned for Monday evenings in Ireland

In an effort to promote activity on digital radio in Ireland and to gauge the level of interest, a new weekly net is starting on Talk Group 2722 on Monday the 24th of Sept 2018.

Extract from the IRTS news...
DMR Net Monday, 24th of September : Steve, EI5DD is planning to hold a National DMR net on Monday the 24th of September at 8:30 pm sharp on the Ireland Calling Channel TG 2722. The purpose of this initiative is to determine how many operators are now active on air and to evaluate the approximate numbers for each county including those in Northern Ireland. Each county will be called in alphabetical order. To keep the activity swift and snappy, please give Callsign, Name, County, and conclude with No Traffic.

The Call-in should only take 15 minutes maximum and there will be plenty of time to hold a free for all QSO at the end of the call ins. If sufficient interest is shown, we may hold this net on a weekly basis.

Update : This ended after 3 weeks.

EI DMR registrations at the end of June 2018

As of the end of June 2018, there were 126 DMR registrations allocated to EI callsigns. It had looked as if the growth in digital registrations had begun to taper off at the end of 2017 but it continued to grow in 2018.

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.

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.

Snapshot of DMR activity in EI - 10th March 2018

After a few contacts earlier today on digital radio (DMR), I began to wonder what the DMR activity levels in Ireland was like among EI calls. After a small bit of digging, I came up with some stats which are current as of the 10th of March 2018.

Some stats...

1) 108 DMR numbers...There are 108 registered DMR numbers issued to EI calls. Even though number 272109 was issued, number 272008 is missing...so that's 108 in total.

2) 100 Individuals (incl 3 clubs)... Eight individuals have two DMR numbers a) EI9IL/EI1UN b) EI3JE c) EI4GJB d) EI4KN e) EI5CA f) EI7IG g) EI8EJB and h) EI9ED. So that makes 108 - 8 = 100 individuals with registered DMR numbers. (Three are clubs but I'll count those as individuals).

3) 46% Heard... Out of the 100 individuals registered for DMR, only 46 have been heard. (49 - 3 duplicates from EI3JE, EI4KN and EI7IG). If that's correct then that means 46% of the those that have registered a DMR number have actually activated it.

4) 41 active in 2018...Of the 46 heard, a total of 41 of these were heard in the first 10 weeks of 2018. That probably represents the current number of EI calls actually active at present on this digital mode.

5) Distribution of activity... Of the 41 heard in the first ten weeks of 2018, this is where the majority were heard last...(as of the 10th of March 2018)...
...a) 21 heard on MMDVM individual hotspots.
...b) 7 heard on EI7WCD in Tramore near Waterford City.
...c) 7 heard on EI7CDD in West Waterford.
...d) 2 heard on EI2GCD in Galway City.

6) Registrations by County... If we count the club calls and account for those with two DMR numbers, this is the breakdown by county (3 and more)...

It breaks down as Cork 14, Galway 13, Waterford 8, Limerick 8, Dublin 6, Louth 6, Clare 5, Mayo 5, Wexford 4, Donegal 3, Tipperary 3, Kerry 3 and Kildare 3.

7) DMR Registrations by Quarter... The chart below shows the total number of registered DMR users in Ireland (EI) at the end of 2017.

It's worth pointing out that the stats above don't show the large pocket of activity in Northern Ireland as well (GI).

Taken all together, there are three pockets of activity in Ireland...in the south-east near Waterford & East Cork, near Galway City and in the north-east near Belfast.

It's amazing there is no real activity yet from near Dublin? Why?

Links...
1) EI registered DMR numbers

Line of Sight to the DMR repeater EI7CDD

After a spell of four years off the radio, I got on air again in late 2016. Once I came back, I found out there were some new developments in the world of digital radio with D-Star, Yaesu System Fusion and DMR. I read up on these but at that stage at the start of 2017, there were no digital repeaters anywhere near me in Cork.

After another short spell off the radio from May to December 2017, I found out in January of 2018 that a new digital repeater with the call sign EI7CDD had been installed in West Waterford in September of 2017.

The new repeater was located on a 300m high hill called Carronadavderg in West Waterford which just so happens to be line of sight to my house!

Carronadavderg is high enough so that it is visible for me over the hills to the north of Killeagh. The repeater is 45kms / 28 miles away.

On any sort of clear day, I can see Carronadavderg on the horizon. This is a photo I took today with a small telephoto lens on the camera. The golf course in the foreground is about 2-3kms away.

The white below the summit of Carronadavderg is a layer of snow while the darker summit is covered in trees.

On closer inspection, some white microwave dishes can be barely seen on the summit when the sun was shining there. The houses in this view are some 25kms distant.

The view was a little better when the dark masts were contrasted against a bright background. I can pick out six masts in total...three large ones and three small.

Pretty amazing what the camera could pick up from 45kms away!

The main thing of course is that it is line of sight from here which allows me to access the DMR repeater with 1w from a TYT MD-380 handheld with a whip antenna.

When I check the Last Heard list for EI7CDD, I seem to have a signal of S4-6 when I stand next to a window here in the house so I can get into the DMR system fine.

EI DMR Registrations...

A few weeks back, I got a registration number for using DMR (Digital Mobile Radio). Considering DMR has its roots in the commercial world, I think that this will become the de facto standard for digital radio on the VHF amateur bands in the future...as opposed to D-Star or Fusion.

I was curious to see how many EI stations have registered to do and I put together the chart above. The 2017 peak coincided with articles in the IRTS newsletter.

The chart below shows the total number of DMR registrations for EI calls at the end of each quarter up until the end of 2017...

As of the 9th of February 2018, there are 106 EI calls registered on DMR. Needless to say, not all of them are active or may even have equipment but it does show a growing interest in this digital mode.

Update 9th March 2018 : Using the 'Heard Users' function, 47 of the 108 registered users have been heard using DMR. That's roughly 44%.