DMR is getting big around here

roger_mull-1024x776I remember seeing some of the first DMR handhelds appear around here about 2 years ago, and I wasn’t really impressed. The audio quality sounded great, but to me it was another infrastructure-heavy type of system that fell somewhere between a repeater on steroids, D-Star and a VOIP system like Echolink.

Apparently here in Columbia, a proof of concept of the system was installed in late 2013 at Little Mountain, and it’s really taken off locally. The large statewide SCHEART network obtained some funding, and the DMR network is now in its second (possibly third?) phase here in the state, with new machines and talk groups being added frequently. I recently participated in a statewide emergency exercise  as a member of Auxcomm, and I noticed DMR radios were in heavy use at the state EOC. Also, every time I get around a group of hams, the subject of DMR comes up. So I thought maybe it was time to learn more.

In an effort to demystify the mode a bit, I asked a local emcomm expert to present a program on DMR at our April club meeting. We had record attendance at the meeting, with many operators I’ve never met coming out of the woodwork to attend. There were no shortage of questions either. For the better part of an hour, we inspected actual DMR hardware (two repeaters, numerous handhelds), viewed real-time DMR traffic on the web, learned about the networked talk groups, time division systems, and a local “bridge” that connects DMR with D-Star and other proprietary systems.

At at the end of the day, the presentation helped me understand the mode and I actually wanted to give it a shot. I don’t currently own a DMR radio, but I suppose I’m in the market — in particular, the Tytera handhelds seems very popular here, and one can be had for a reasonable $140 or less on Amazon. Programming is obviously important, and the folks at SCHEART release new “code plugs” frequently as the network expands.

First steps:

  • Before purchasing a DMR rig, register your callsign at DMR-MARC. This is the “master listing” of DMR users to prevent ID/callsign conflicts. You can’t really use your radio until you have an ID.
  • Get a radio. The Tytera 380 is popular here, and cheap. Offerings from Connect Systems and of course, Motorola are also popular, with the latter being many more times expensive.
  • Get some code plugs. NCPRN.net and SCHEART.us have the most recent files. These are programming files that contain info about the repeaters on the system.
  • Use the radio: Select the proper zone for your area and choose a talk group. It’s helpful to understand the architecture of the network, and know exactly what’s happening in the background too. For example, if you key up on the entire “PRN” network, you are simultaneously bringing more than 40 repeaters across the eastern US online. You probably don’t want to use PRN for ragchew, so you should move your QSO to a more localized “chat” frequency.

Download the presentation

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