Talkgroups: static vs dynamic — how to subscribe without getting in the way

You spin your radio through the channels: on one you hear constant traffic, on another there's silence until you press PTT yourself. That's exactly the difference between static and dynamic talkgroups. Let's break down how they work, how to subscribe to the group you want, why a subscription "drops" on its own, and how to use all this without becoming the person who hogs a popular TG for half a day.

What a talkgroup is

A talkgroup (TG) is a virtual channel inside a DMR network — a kind of "room" organized by interest or geography. Every group has a numeric ID (for example, 9990 is the echo test; local groups have their own numbers). When you transmit on a channel set to a particular TG, you are heard by everyone who is currently "listening" to that same group through any repeater or hotspot across the whole network. Don't confuse a TG with a frequency: a single repeater frequency can "host" many different groups, and the same group is available on thousands of devices at once.

The key question for a newcomer is which groups your hotspot can actually hear right now. The answer depends on whether they are static or dynamic.

Static TGs: always connected

A static talkgroup is permanently "linked" to your hotspot or repeater on a specific timeslot. Its traffic reaches you at all times, with no action on your part — even if you haven't pressed PTT once all day. A static link is configured by the repeater owner (or by you on your own hotspot) once, and it stays in place until it is manually removed.

• Pro: you won't miss traffic from the group you care about — it comes through on its own.
• Con: if you make too many active groups static, the hotspot's air will be constantly busy, and dynamic subscriptions will get "drowned out" by other traffic.

Dynamic TGs: subscribing with a PTT tap

A dynamic talkgroup connects "on demand." The mechanics are almost embarrassingly simple:

1. Select the channel with the group you want on your radio (it must already be defined in your codeplug).
2. Give a short PTT tap — literally key up for 1–2 seconds (you don't even have to say anything).
3. The network "subscribes" your hotspot to that group: from then on you hear all of its traffic and can talk.

A subscription does not last forever. If there is silence for about 10–15 minutes — both from you and on the air in the group — the network automatically unsubscribes your hotspot so it isn't shuffling traffic for nothing. Any activity (yours or someone else's) resets the timer. On large networks like BrandMeister the time-out is usually 15 minutes without local traffic.

How to add a static TG on your own hotspot (in DMRhub)

If a group should come through for you at all times, it's more convenient to make it static via the panel rather than tapping PTT every 15 minutes. In DMRhub this is done in your dashboard:

1. Open your dashboard and go to your hotspot.
2. Find the section with the hotspot's list of static talkgroups.
3. Add the group number you want and save — the hotspot agent will pick up the config and write the link on the correct slot itself.

After that, the group will be audible as soon as the hotspot starts, with no manual key-ups. To remove the static link, do it in the same place: delete the number from the list and save.

Parrot echo test (9990)

Parrot is a built-in echo service: it records your transmission and plays it back a second or two later. It's the ideal way to confirm your radio really reaches the network and to hear your own audio from the outside (level, distortion, "muddiness").

Parrot is reached with a Private Call to ID 9990, not as a group channel. Define a channel in your codeplug with the contact "Parrot 9990," call type Private Call, then hold PTT and say a couple of phrases. Let go — and a moment later you'll hear your own recording come back as a private call.

Channel:      Parrot / Echo test
Contact (TX): 9990
Call type:    Private Call
Timeslot:     TS2 (for a hotspot)
Test:         press PTT → say 2–3 phrases → release → hear the echo

Slots: on a simplex hotspot, only TS2

DMR splits the time on a channel into two slots — TS1 and TS2. On a full duplex repeater you can spread static and dynamic links across both slots. But a simplex hotspot (a single transceiver that can't listen and transmit at the same time) works on one frequency where there is no true split into two slots — and by convention all of its traffic goes as TS2. So all your channels for a simplex hotspot must be on the second slot: whatever you set on the radio, the network will still see TS2.

Etiquette: don't hog the air, and unsubscribe

A talkgroup is a shared resource. A few simple rules so you don't get in everyone's way:

• Don't "park" static links on popular groups for no reason. The more active static links sit on a hotspot, the more tightly its single slot is occupied — and the worse your own dynamic subscriptions get through.
• When you're done, unsubscribe. You don't have to wait out the 15-minute time-out: you can "unlink" all dynamic groups manually by sending a group call to TG 4000. This drops all dynamic subscriptions and links at once.
• Don't "step on" someone else's conversation. While someone is talking in the group, leave a 2–3 second gap between transmissions — otherwise you cut people off and prevent others from breaking in.
• Remember "channel hang." While there is active traffic on the channel, it can be impossible to switch to another group with the PTT button — the system holds you on the busy TG. One more reason not to make everything static.