Newcomers to digital voice radio run into two words almost immediately — reflector and talkgroup — and the guides usually assume you already know what they mean. They are not the same thing, they don't come from the same part of the hobby, and using one term when you mean the other is one of the most common sources of confusion. This page explains what each one is in plain language, then shows how the idea takes a slightly different shape in each digital mode.
A reflector is a server on the internet that acts as a central meeting point for digital voice radio. On its own, a handheld or a local repeater can only reach as far as its signal carries. A reflector removes that limit: radios from all over the world connect up to the same server, and the server copies — reflects — whatever it receives back out to everyone else who is connected. That's the whole idea behind the name. When you key up, the reflector takes your audio and bounces it to every other station in the room.
The radios themselves never talk directly to each other. Each one has an internet path to the reflector, and the reflector sits in the middle. Picture a conference call: nobody dials every other participant individually; everyone dials into one bridge, and the bridge connects them all.
You don't connect to a reflector directly from your radio over the air. You reach it through a device that has both a radio side and an internet side — usually a personal hotspot sitting on your desk, or a repeater that has been set up to link to reflectors. That device handles the internet connection; your radio just talks to it on RF, the same as always.
A talkgroup is a channel within a network — a label that decides who hears your transmission. The word comes specifically from DMR, the most popular digital mode, where a talkgroup is simply a number. Talkgroup 91 might be the worldwide channel, 31 the North America channel, 310 some statewide chat, and so on. When you transmit on talkgroup 91, the network routes your audio to everyone currently listening to 91, and to no one else. Change the number and you've changed the room.
So the two words describe different things:
The reason they get tangled together is that both end up answering the same practical question — who is going to hear me when I key up? — and in some modes the lines genuinely blur. A large DMR network like BrandMeister is really one enormous distributed system with thousands of talkgroups; you pick a talkgroup, not a server. A D-Star or M17 reflector, by contrast, is a single named server you point your hotspot at. Both get you into a shared room. They just organize the rooms differently.
Most reflectors don't offer just one conversation. They're divided into separate, independent rooms so that several unrelated chats can run on the same server at once. Depending on the mode these subdivisions are called modules, rooms, or talkgroups, but the idea is identical: pick a room, and you hear only the people in that room.
On XLX and URF reflectors the rooms are modules, labeled by letter from A to Z. Everyone on Module C hears each other; that conversation is completely separate from Module D on the very same server. (The XLX guide develops this with a hotel-and-rooms picture — the reflector is the hotel, the modules are its 26 rooms.)
Every digital voice mode has some version of "connect to a shared place and pick a room." The terminology is just different in each one — which is the real reason the vocabulary feels so messy. Here is the same concept translated across the modes.
| Mode | What the shared server is called | What the rooms inside it are called |
|---|---|---|
| D-STAR | Reflector (REF / XRF / DCS / XLX, by linking protocol) | Modules, lettered A–Z |
| DMR | Network (BrandMeister, TGIF, etc.) — a distributed system, not one box | Talkgroups, numbered — carried on one of two timeslots |
| C4FM / Fusion | YSF Reflector (and Wires-X rooms) | The reflector is usually one room; Wires-X has rooms by number/name |
| M17 | Reflector (mrefd) | Modules, lettered A–Z |
| P25 | P25 Reflector / network | Talkgroups, numbered |
| NXDN | NXDN Reflector / network | Talkgroups, numbered (with a RAN as an access code) |
Read down that table and a pattern appears. The modes that grew out of the D-Star world — D-Star itself, and M17 — organize themselves as named servers with lettered modules. The modes that grew out of the commercial land-mobile world — DMR, P25, NXDN — organize themselves as networks with numbered talkgroups. Fusion sits in between. None of it is arbitrary; it reflects where each mode came from.
"Reflector" is a role, not a single program. Several different pieces of software fill that role, and which one a given server runs determines what modes it can host. The common ones in amateur radio:
xlxd)The workhorse multi-protocol reflector. A single XLX module can accept D-Star, DMR, and Fusion connections at once. With hardware transcoding added, all three can hear each other. It grew out of D-Star and is still one of the most widely deployed reflector systems. (Full detail in the XLX guide.)
urfd)The successor to XLX — a "universal" reflector. It does everything XLX does and adds M17, NXDN, P25, and USRP/AllStar support, with a more capable transcoder. If you want one server that bridges the widest range of modes, this is it. (Full detail in the URF guide.)
mrefd)The native reflector for the open-source M17 mode. Lettered modules A–Z, like D-Star, but built around M17's fully open codec and protocol. (Full detail in the M17 guide.)
The reflector for C4FM / Yaesu System Fusion. Typically presents as a single room that Fusion hotspots and repeaters link into, and it underpins much of the Fusion networking world.
Smaller but active corners of the hobby, each with its own reflector software, organized — true to their land-mobile roots — around numbered talkgroups rather than lettered modules.
DMR is the odd one out. Instead of you picking a single reflector server, DMR is built as large networks — BrandMeister, TGIF, and others — each a sprawling distributed system you join, after which you choose among thousands of numbered talkgroups. There's no single "DMR reflector" to point at; the network is the meeting place, and talkgroups are the rooms. (See How a DMR Network Works and BrandMeister and TGIF Compared.)
One last piece worth knowing, because it cuts across every mode. There are two ways to put your hotspot or repeater into a room:
Static links are how you keep a permanent presence in a favorite net. Dynamic links are how you go visit somewhere briefly without committing to it. Most operators run a couple of static rooms they always monitor and reach everything else dynamically.
Here's the apparent contradiction that sends people in circles. A YSF reflector is a reflector. An XLX reflector is a reflector. But DMR — supposedly — doesn't have reflectors; DMR has talkgroups. And yet one DMR network, DMR+, plainly uses both: it has talkgroups and it has reflectors, at the same time. How can that be?
The answer is history. DMR didn't arrive in amateur radio as one unified thing — it arrived as competing networks that made different design choices, and two of them went opposite directions on this exact question.
IPSC2 server software, and is the network behind many regional systems worldwide) came out of the older European reflector-linking tradition — the same way of thinking that gave us D-Star reflectors. DMR+ kept reflectors alive inside DMR rather than throwing them out. So it carries both mechanisms side by side.That's the whole reason DMR+ "uses both." It isn't a contradiction — it's two layers that DMR+ chose to keep separate, where BrandMeister chose to collapse them into one.
DMR+ splits the work across the two DMR timeslots, and it uses two different kinds of call to keep dialing-to-talk and dialing-to-link from getting mixed up:
The reflector command set is fixed and worth memorizing, because it's identical on every DMR+ server:
| What you want to do | Type of call | Number |
|---|---|---|
| Link to a reflector | Private call | 4001–4999 (the reflector's own ID) |
| Talk on the reflector you linked | Group call | TG 9 (local) |
| Listen to the reflector | (automatic) | it comes back to you on TG 9 |
| Unlink / disconnect | Private call | 4000 |
| Ask "what am I linked to?" | Private call | 5000 |
So 4001 through 4999 are reflectors, 4000 is the off switch, and 5000 is the status check. You can only have one reflector linked at a time — link a new one and the previous one drops. By convention the reflector machinery lives on timeslot 2, leaving timeslot 1 free for ordinary talkgroups, which is how a single DMR+ hotspot can offer both at once without the two colliding.
Picture it as a car. The talkgroup is the talking; the reflector command is the steering wheel. On BrandMeister the steering wheel was removed because every street has its own dedicated number — you just dial where you want to be. On DMR+ the steering wheel is still there: you steer (private call to 4001–4999), then you talk (group call on TG 9).
One more wrinkle, and it's the deepest source of the "reflector or talkgroup?" confusion. On DMR+, a reflector and a talkgroup can be two doors into the same room. Reflector 4001, for instance, is the Berlin-Brandenburg room — and that room is also reachable as a regional talkgroup. Same conversation, two ways in: link the reflector and talk on TG 9, or dial the regional talkgroup directly. This is exactly why a single net can be described as "a reflector" by one operator and "a talkgroup" by another and both be right. They're naming two different doors to one room.
If you run a hotspot that connects to several DMR networks at once through a DMRGateway (BrandMeister + DMR+ + an XLX server, say), you've seen numbers like 84000, 85000, or 64001 in your contacts and wondered where they came from. They exist to solve a collision: BrandMeister, DMR+, and XLX all use overlapping command numbers (everybody wants 4000 as the off switch), so the gateway gives each network a prefix to keep them straight — commonly an 8 in front for DMR+ (84000 to unlink, 85000 for status) and a 6 for XLX (64001–64026 to pick modules A–Z). The bare command is the same; the prefix just tells the gateway which network you're aiming at. (See Understanding the DMR Gateway.)
A reflector is a place — a server in the middle that copies your audio out to everyone connected to it. A talkgroup is a channel — a label, almost always a number, that sorts traffic into separate conversations within a network. The two aren't rivals; they're different layers. A reflector is where you end up; a talkgroup is how you dial. Most modes only show you one layer at a time — D-Star and M17 point you at named reflectors, BrandMeister hands you pure talkgroups — which is why the words seem to belong to different worlds. DMR+ is the one network that keeps both layers visible and working together, and once you see it that way, the contradiction disappears: you steer with a number, and you talk in a room. Underneath all the different vocabulary, every one of these systems is doing the same simple thing — gathering radios from everywhere onto the internet, so that keying up in San Jose can put you in a room with someone in Tokyo.