DMR Simplex Direct Messaging

You can send a direct (text) message between two DMR radios, if know the other person's DMR ID (You can look up ID by callsign here: https://database.radioid.net/database/search). Start by selecting a DMR channel on your radio. Common DMR Simplex channels include:

UHF Frequencies:
441.000 MHz
441.500 MHz
446.500 MHz
433.450 MHz

VHF Frequencies:
145.790 MHz (used in some areas)
145.510 MHz (used in some areas)

Channel Configuration:

When programming DMR simplex channels, the following settings are commonly used:

Talk Group (TG): 99 (a common convention for simplex use)
Color Code (CC): 1 (a common convention for simplex use)
Time Slot (TS): 1 or 2 (depending on the radio and desired functionality)
Admit Criteria: Always or Channel Free (depending on the desired behavior)

Both radios MUST be on the same channel and talk group in order to receive DMR direct messaging. Because the messages are direct (private) they are only received by the radio ID to which they are addressed. (While all radios on the channel hear the transmission, only the radio ID that the message is addressed to will copy and save the message.)  

In order to send a DMR direct message, go to the menu tab on your radio and click messages or SMS. Select "Create new message". Simply type your message into the "compose message" box. Once you are done, select the send message button, select "Manual Dial", and type the DMR id of the other amateur you are trying to contact. You can save time by adding them as a contact to the radio if you message them often. You will receive a notification saying "message successful" or "message sent". (This procedure may vary slightly based on the type of DMR radio you are using.)

When received the radio will store the DMR text message in memory (the inbox) until it is read and deleted by the user. You can receive DMR text messages without having to be actively monitoring your radio - as is necessary to receive a voice call. DMR text messages will also sometimes go through when a voice connection isn't possible.



* DMR direct messaging will also work through the Brandmeister network, assuming both the sender and receiver are connected to the network.  

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