What Is DMR and How Do You Program It?
DMR (Digital Mobile Radio) is a digital communication standard used in amateur radio,
public safety, and commercial systems. It’s prized for its efficient spectrum use—allowing
two simultaneous conversations on a single frequency via Time Division Multiple Access
(TDMA).
When programming a DMR radio, you’re essentially defining:
- Who you want to talk to (Talk Groups)
- What you want to hear (Receive Lists)
- How your radio accesses it (Channels)
- How it’s organized on the radio (Zones)
Understanding these building blocks allows you to fully tailor your radio to your personal or
mission-specific communication needs. template page created by Superb Addons. You can edit this page’s content and its template. If the blocks you want to edit can’t be found in the page content, please edit the selected template.
Talk Groups (a.k.a. Group Contacts)
Talk Groups are the digital equivalent of “rooms” where operators gather. Each one is:
Using the correct time slot ensures your transmission reaches the intended network
and doesn’t interfere with other traffic
So, when selecting a talk group, you’ll usually need to know its assigned time slot on
your target repeater or hotspot.
Time slots are essential in DMR:
- Assigned a unique numeric ID (e.g., TG 91 for Worldwide)
- Programmed as a Group Call contact type
- Paired with a channel to direct your transmission
- Often associated with a specific time slot on a repeater or hotspot.
Important: The Receive List does not affect who you transmit to—only who will open
your radio’s squelch during receive.
DMR Channels
A Channel is a bundle of configuration data that determines:
- Most repeaters and hotspots support two simultaneous paths, called Time Slot 1
and Time Slot 2 - A talk group will typically be designated for use on one specific time slot (e.g., TG91
on Slot 1, TG310 on Slot 2) - Using the correct time slot ensures your transmission reaches the intended network and doesn’t interfere with other traffic
So when selecting a talk group, you’ll usually need to know its assigned time slot on
your target repeater or hotspot.
Receive Lists (Talk Group Lists)
A Receive List tells your radio which talk groups to listen for when idle on a particular
channel.
- If omitted, you’ll only hear transmissions on your set talk group.
- If included, it allows monitoring multiple groups—ideal for busy repeaters or
hotspots that carry several conversations. - TX & RX Frequencies (often defined by a repeater or hotspot)
- Color Code (similar to CTCSS/DCS for DMR)
- Time Slot (1 or 2)
- Transmit Contact (the talk group you’re transmitting to)
- Receive List (what talk groups will open the squelch)
Each channel represents one unique way of communicating through your radio.
Example channel:
Define “TG310” as 310 and “TG311” as 311 and define “My Receive List” as containing TG310 and TG311
| Name | Value |
| TX Frequency | 449.000 |
| RX Frequency | 444.000 |
| Color Code | 1 |
| TIme Slot | 2 |
| Contact | TG310 |
| Receive List | My Receive List |
Zones
Zones are like folders on your radio. They help you logically group your channels for easy
access.
- You can organize by region (e.g., Boston, Western MA), function (Simplex,
Repeaters/Hotspots), or role (Emergency Ops, Events). - Most radios limit channels per zone (e.g., 16 or 32).
- Some radios allow browsing all channels without zones—zones are optional on
many models.
Zones are purely organizational—they don’t change how your radio operates, but they
dramatically improve usability.
Putting It All Together – Sample Workflow
Let’s say you want to program TG310 (TAC 310) for your local repeater or hotspot:
- Create Contact: Add TG310 in your CPS as a Group Call contact.
- Build a Receive List: Include TG310 and TG311 if you want to monitor both.
- Make a Channel: Use the repeater or hotspot’s frequency, color code, and
designated time slot. Assign TG310 as the transmit contact and your receive list. - Add to a Zone: Place this channel alongside other commonly used ones for quick
access in the field.
Repeat this process for additional talk groups or other infrastructure.
