DMR

The Radio reference says which radios have DMR verified. DMR voice needs the codec (Installing) and a DMR ID in the codeplug.

Terms

Who you hear

The radio plays a group call when one of these is true:

• its talkgroup is the talk target's talkgroup, or the call is an all call;
• its talkgroup is in the channel's listen list;
• it is the reply target during the reply window (below);
• digital monitor is on.

The radio plays a private call addressed to your DMR ID. It shows every other call on the slot as "Other TG: not played" and treats the channel as busy while it lasts.

Who you talk to

PTT sends to, in this order:

1. The talkgroup or person with the focus in a list, once (one-shot).
2. The reply target, while the reply window runs.
3. A talk target chosen for now.
4. The channel's talk target from the codeplug. A channel without one talks to the first talkgroup of its RX group list, and uses talkgroup 9 only when it has no list either.

Home shows the result after "PTT→".

Choosing a talk target

Hold # on a DMR channel to open the talk target picker: the channel's default, the reply target, the RX group list's talkgroups, recent talkgroups, and "Type a number..." to dial an ID or talkgroup by hand. The Talk target side key opens the same picker.

A talk target has three lifetimes.

A permanent talk target must be a contact in the codeplug. A typed number is used for now only. The radio shows "Not a stored contact: for now only".

The talk target picker

Press Talk target on a DMR channel (or *, 8). The picker lists, in order:

The focus starts on the reply row when there is one.

"Type a number..." opens Find. Type the talkgroup or ID, focus the line you want and press PTT or OK.

On an FM channel Talk target shows "Talk target: DMR channels only".

Typing a talkgroup or ID

On Home, type the number. Find lists "Talk to TG 3100" and "Private call 3100" (with a name when the ID is a contact). Focus one and press PTT for one call, or OK for now.

Replying

After a call the radio played, the reply window opens. During the window PTT answers the call. A group call is answered on the same talkgroup, a private call to the caller. After your own call, PTT goes to the same target again. Home shows "Reply→" with the target and a countdown.

The window lasts as long as Settings > Talk & listen > Reply window says (0 to 30 s). 0 turns it off. When that setting is left at its start value, the codeplug's hang time applies. Without a hang time in the codeplug, the window lasts 10 s. Back on Home ends the window ("Reply ended").

Calling back later

On Home, # opens the actions for the current or last caller. A digit picks an action.

For a talkgroup the actions are Talk to, Make channel default and Message.

Without anyone heard yet, # shows "No calls heard yet".

Recent

OK, 3. Recent lists the last 12 stations heard and calls made, newest first. Calls you made start with an arrow. Calls to you are highlighted, and private calls show "you" or "priv". Recent is kept in memory and starts empty after a restart.

PTT talks to the focused entry (the talkgroup a station was heard on). OK uses it for now. Holding OK makes it permanent. # opens its actions.

Contacts

OK, 1 lists the codeplug's contacts and talkgroups. Type letters of the name, or digits of the ID, to filter. OK talks to the focused entry for now. Holding OK makes it the channel's default. PTT talks to it once. # opens its actions.

Contacts can't be added or edited on the radio yet. Use qdmr.

Private calls

• From a contact: OK, 1, find the person, #, 2 (Private call), then PTT. Or focus the person and press PTT.
• By ID: type the ID on Home, focus "Private call ..." and press PTT.
• To answer a private call, press PTT during the reply window.

While you talk, the top line says "Private" and the screen shows the contact's name (Transmitting).

Timeslot and color code

On a DMR channel, * opens these tiles:

To change the color code, press *, 3. Press Up or Down, or type the code (0 to 15). Press OK to apply it. The new color code takes effect when the editor closes.

Timeslot and color code are temporary. They can't be changed while transmitting. Hold OK to save them to the channel. In the VFO they are the VFO's own settings and are kept (the VFO).

Waking a repeater

A repeater that is idle may need a wake-up before it carries your call. On a repeater channel (TX and RX frequencies differ) the radio sends the wake-up when you press PTT and then waits for the repeater to answer. A short press is enough: let go of PTT and the radio keeps trying, up to the usual number of attempts.

Digital monitor

Digital monitor plays every talkgroup on this frequency, timeslot and color code.

• Press Monitor on a DMR channel (a short press; it acts when you let go). The radio shows "Digital monitor on" and the chips show "DMon". Press it again to turn it off. On an FM channel the same key opens the squelch while you hold it.
• Or *, 5.

Digital monitor stays on until you turn it off, change the channel or the mode, or press Back on Home. While it is on, the reply window lets you answer any call you heard with PTT.

Privacy

RadioFoundry has two kinds of basic privacy: Motorola basic privacy (keys 1 to 255) and Anytone 16-bit basic privacy. Basic privacy is a fixed scrambling of the voice. It keeps casual listeners out but isn't encryption. The scrambling hasn't been checked against another radio yet (Radio reference).

• The radio plays an encrypted call only when it has the matching key. Without the key the call shows as "Encrypted: not played".
• Calls with stronger encryption (they send a PI header) are never played.
• *, 6 turns privacy on for your calls ("Privacy on for now"). Home shows "Priv". Back on Home turns it off again.

To set the key on the radio, open Settings > Privacy (OK, 7, 4).

1. On Key type, press OK until it shows Motorola or Anytone.
2. On Key, press OK. Type the key in decimal with the number keys (Motorola 1 to 255, Anytone 0 to 65535). Press OK again.

The radio keeps the key across restarts. Setting the type back to Off removes the key and turns privacy off. The codeplug can't hold privacy keys yet. Developers can also load a key over USB with the debug tool:

tools/rfoundry_debug.py radio privacy moto 5          # Motorola basic privacy, key 5
tools/rfoundry_debug.py radio privacy anytone 4660    # Anytone basic privacy, key 4660
tools/rfoundry_debug.py radio privacy off

Without a key, the Privacy tile shows "No privacy key: set one in Settings > Privacy". The keys are stored without protection in the radio's flash.

Position in calls

Some DMR radios send their position inside a voice call (ETSI GPS Info). When a caller does, the receive screen shows how far away it is and in which direction, for example "12.3 km NE". When the radio doesn't know your own position, it shows the caller's coordinates. Recent keeps the distance with the call.

Your own position goes into your calls when Tools > APRS > Position in DMR calls is on (off by default) and the radio knows where it is (see APRS). Every other superframe carries it, taking turns with your talker alias.

Talker alias

The receive screen shows the talker alias other radios send, as it arrives. Settings > Talk & listen > Show talker alias turns this off. The radio sends your callsign from the codeplug (8 characters) as your own alias when the channel's talker alias setting in the codeplug asks for it.

Roaming

On a system of DMR repeaters that carry the same talkgroups at different sites, the radio can move to a better repeater by itself when the one it's on gets weak. You turn roaming on per zone.

1. Put the repeater channels of one system in a zone, each set to the same contact.
2. Pick one of them, then open Tools > Roaming and turn on Roam in this zone.

While idle, the radio watches the signal of the repeater it's on. When the signal stays below the threshold, the radio listens to the zone's other sites and moves to the strongest one it can hear. It never moves during a call, a scan or hotspot use, while you transmit, or in the 3 seconds after a call ends, when a reply may come. Home shows Roam next to the repeater chip, or an amber Roam? when the current site is weak. The status strip shows ROAM during a search. A toast says "Moved to" and the new channel's name.

Many repeater systems make every repeater transmit briefly while idle. This is a "beacon", for example 4 s every minute, all at the same moment. The radio learns when its repeater's beacons come. During each beacon it hops to a few of the other sites for under a second each, measures them and comes back. The screens keep showing your repeater. A key press, PTT or a call on the visited site brings it straight back. A call that starts on your repeater while the radio is away is joined up to about 3 s late, so the radio skips the survey for a while after traffic. When your repeater gets weak, the radio checks the best site it measured at the next beacon and moves there, usually within a minute. Set Beacon interval and Beacon length to match the system (ask its operator). If each repeater beacons on its own schedule, pick Per site. If they don't beacon, pick None: the radio then relies on calls it hears. The screen says "Beacons: learning" until the radio knows the schedule, then "Beacons: surveying".

A site is a repeater channel in the zone (TX and RX frequencies differ) with the same contact as the channel you picked. When any channel in the zone has the codeplug's Roaming flag set, only flagged channels are sites. You need at least two sites. Changing channel or zone yourself makes the new channel home.

The threshold (default -105 dBm), the hysteresis (6 dB) and the optional periodic search of the other sites are set over the debug link for now (dmr-roaming section 5.1). The debug link also sets the idle beacon that a hotspot running MMDVM SFR can send for roaming radios (rpt_beacon, off by default).

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