Palmetto DMR

The Palmetto Amateur Radio Club’s Talk Group is on TG 3202487.

To see who was last heard on the TG, click here.

DMR can be overwhelming initially, but once the initial state of intimidation is overcome, it is a great way to make “DX” QSOs without actually DXing. It will open doors for your HT you never thought would be possible.

DMR is a digital form of communication that combines RF with digital transmission over the internet. This is very important to realize because in an emergency, when the grid is down or when you have no internet service, DMR will not work.

There are multiple DMR networks. The PARC is utilizing the Brandmeister DMR network.

What do I need for DMR?

First, you need to be a licensed amateur radio operator with a valid call sign, and with that, you can apply for a DMR ID. To apply for a new DMR ID, click here.

The next thing you need is a radio that is DMR capable. That can be an HT, e.g., the AnyTone 878UVII Plus, or a mobile radio. As long as the radio is DMR-capable, you are good to go. Then you need a DMR-capable repeater in your area or a hotspot.

Let’s talk about general terms and configuration.

General Settings

The first thing you need to know is, of course, the frequency. The other 2 essential things you need to know are the Color Code (CC) and the Time Slot (TS).

Color Code (CC)

There are 16 different CCs. To access the repeater/hotspot, you must program the correct CC. CC is the equivalent of CTCSS on the Analog side. While the CTCSS is optional for an analog repeater, the CC is not. The only real purpose of the CC is when multiple repeaters operate on the same frequency with overlapping coverage.

Time Slot (TS)

You also need to know what TS the repeater is listening to. DMR Tier II/Tier III occupies 12.5 kHz bandwidth that two channels share using Time-Division Multiple Access (TDMA).

This results in a spectrum efficiency of 6.25kHz per channel. Comparing the spectrum efficiency of DMR to a wideband analog FM, DMR only uses 25% of the bandwidth per talk channel.

Each channel can carry either voice and/or data depending on system design. The two time slots are Time Slot 1 (TS1) and Time Slot 2 (TS2).

Talk Groups (TG)

Talk Groups (TG) are a way for groups of users to share a time slot (one-to-many) without distracting and disrupting other users of the time slot. It should be noted that only one Talk Group can be using a time slot at a time. If your radio is not programmed to listen to a Talk Group, you will not hear that Talk Group’s traffic.

The DMR standard also supports private calls (one-to-one), encryption, and data. Private calls are not allowed by most amateur networks, and many consider private calls not amateur-friendly; private calls tie up many repeater time slots across the network. Encryption is not legal on amateur radio! Data and text messaging are supported on some networks.

DMR Simplex Frequencies

The standard for simplex traffic in the amateur community is to use TG99 on TS1 with CC1.

UHF Simplex Channels:

  • 441.0000 MHz
  • 446.5000 MHz
  • 446.0750 MHz
  • 433.4500 MHz

VHF Simplex Channels:

  • 145.7900 MHz
  • 145.5100 MHz