Pretty cool news! The Liverpool Amateur Radio Club is investigating a a DMR repeater and providing DMR tech training sessions In Syracuse.Press release from LARC on their DMR plans:
Liverpool
Amateur Repeater Club (LARC) Plans for Digital Mobile Radio (DMR)
August 6,
2018
DMR has been a hot topic of late and the LARC Board of
Directors (the “Board”) has engaged in many discussions on the topic over the
last year. At the August 6 board
meeting, the Board passed a motion to bring to the membership at the September
meeting a funding authorization, pending successful evaluation (see below), for
the purchase, configuration and deployment of a LARC DMR repeater for the greater
Syracuse area. If one looks at some of
the DMR footprints in Upstate NY, there is a very noticeable DMR void in the
Syracuse area. Repeaters exist both to
the East and West of us. The Board
believes now is an opportune time to embrace the technology as it is clearly
here to stay.
The Board has reached out and met with several fellow hams
with extensive experience in design and implementation of DMR repeaters. Very early in that process, it was apparent
that creating a successful DMR presence was much more than standing up a
conventional repeater. DMR is not about
RF. It is a highly sophisticated
Information Technology project. Anything
installed must be fully compatible with an existing infrastructure. The programming of compatible radios is,
again, highly technical. One must fully
understand both sides of that equation for successful and efficient
implementation of a DMR repeater.
There are two primary DMR networks in the amateur radio DMR
community, DMR-MARC (http://www.dmr-marc.net/)
and BrandMeister (https://brandmeister.network/). There are some key differences in the
networks but suffice it to say, bridges exist between both. Much of the current local DMR community is
using BrandMeister via hotspots (e.g., SharkRF OpenSpot, Pi-Star, etc.) as no
local DMR repeaters exist. DMR-MARC on the other hand, does not permit hotspots
and is purely repeater based for local traffic with Internet as the backbone for
inter-repeater traffic. Within the DMR-MARC
network C-Bridge provides for the IP interconnectivity of DMR-MARC
repeaters. It is important to note that
the repeater in question is capable of running on either network. It becomes a
“simple matter of programming” as the saying goes.
We were fortunate to obtain a Motorola SLR5700 DMR repeater,
at no cost to LARC, for experimentation and educational purposes. If approved by the membership, LARC will
purchase the repeater for production deployment. Several LARC Board members have formed a
working group to integrate all the necessary pieces and create a temporary
installation for evaluation purposes.
The Board welcomes any DMR knowledgeable working group membership from
the club. We intend to utilize the DMR-MARC
network utilizing the C-Bridge network in Upstate NY which will integrate well
with the Upstate NY DMR-MARC infrastructure.
As the working group
moves forward with DMR evaluation and testing, the 443.3 machine will be
unavailable as testing of the DMR repeater will leverage 443.3 site, frequency,
duplexers and antenna.
Should this evaluation prove successful, the group will
present their experiences and recommendations to the general membership at our
September meeting. All hams, members or
not, are welcome to attend that meeting.
Should the general membership recommend approval, LARC will then
purchase and install a permanent DMR repeater in Syracuse. Additionally, should the concept be approved,
we intend to implement a comprehensive educational program for all hams. This will explain the infrastructure, provide
guidance in radio programming, and offer a programming service for most DMR
radios. There are some technical considerations that the Board must
consider and, in some cases, membership insight must be considered.
·
Location: The DMR repeater will be a UHF
repeater. One option is to replace the 443.3 Fusion repeater with the DMR
repeater as that site already has antenna, duplexers and is a prime repeater
location. It is important to note;
reliable cell service is important as a cellular modem is required to provide
the back end inter-repeater C-Bridge connectivity. The current 443.3 site has a new AT&T cell
tower just outside the repeater building and we get 5 bars inside the building
mitigating the need for an external cellular antenna. The other option would be to leverage the
Cazenovia location which currently is VHF only.
Cazenovia coverage is not as good as the 443.3 site and an additional
set of duplexers and an antenna would be required. LARC does have a spare UHF
duplexer and will have to test it to assess health. A third option is to relocate the 443.3
machine to Cazenovia and stand up DMR at the current 443.3 location. This option would require coordination with
UNYREPCO (Upstate NY Repeater Council), the frequency assignment body for
Upstate NY repeaters.
·
Code Plug Management: DMR radio programming is
100% dependent on use of “code plugs” which provide the radio with its
“personality”. Although code plugs all
provide the same capabilities, each vendor has their own software for code plug.
The Board envisions a body of subject matter experts that can assist members in
programming their radios for those that do not have experience in code plug
management.
·
C-Bridge talk group administration and
management: As with any complex managed infrastructure, membership may have
many wants and/or desires regarding talk group management. Given this is new
technology to us, the Board and ultimately the DMR repeater trustee(s) will
have to adopt some form of Request for Change (RFC) process by which membership
requests can be addressed. As was stated
earlier, this is less about RF and more about Information Technology.
I cannot express the importance of understanding that, at
this point, all of this is an experiment.
Nothing will be permanent until the General Membership votes to support
this energetic project. We realize that
there is already a plethora of misinformation and unsubstantiated rumor. Hopefully, this will clarify the
misconceptions and offer anyone interested the opportunity to participate and
provide their observations.
Thanks for your continued support in advancing Amateur Radio
in Central New York.
Sincerely,
LARC Board of Directors
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