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.
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| 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.
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| 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.
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| 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
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