Setting up Dynamic Mixed Mode and Extended Range Direct Mode in a repeater

Tuesday, October 20, 2020

Dynamic Mixed Mode is a repeater feature that allows a standalone repeater to support analogue and digital users. When configured for this, the repeater will switch to analogue whenever an analogue signal is detected. If you plan to use Dynamic Mixed Mode you must use PL or DPL or else the analogue users will hear the digital bursts (which will not be pleasant for them).

Extended Range Direct Mode is also a repeater feature that allows repeater type operation on a simplex frequency. The radios and repeater will all transmit on one slot and receive on the other. The repeater will have the same transmit and receive frequency.

To set up either, start by adding a channel to the repeater. For ERDM choose a regular digital channel (A) and for DMM choose Dynamic Mixed Mode (B).


In either case, the existing (default) channel can be deleted.


Open the channel set and - in the case of Dynamic Mixed Mode - set the following:

  • Colour Code - this should match the radios.
  • Audio Enhancement - unless you know what this is, I would leave it set to None.
  • TX and RX frequency - per your spectrum licence
  • TX and RX PL or DPL code - per your spectrum licence and/or must be the same in analogue radios
  • Unmute Rule - AND unmute
  • Timeout Timer - no more than 240s in my opinion
  • TX power - per your spectrum licence


If you are adding a ERDM channel, then there are some additional settings needed. Firstly, the ERDM licence needs to be loaded into the repeater (see below).


If you are using an antenna switch then you need to set one of the GPIOs to TX7RX switch. NB NB NB! this is not an antenna relay - this is a high-speed antenna switch that uses (amongst others) PIN diodes to achieve the <1,25ms changeover time and 27,5ms switching rate between the transmit and receive ports. If you don't have an antenna switch you will have to use two separate antennas.


Then, in the channel set, you would set:

  • Extended Range Direct Mode - Enabled
  • Inbound and Outbound Colour Code - I generally set both to 1
  • TX and RX frequency - must be the same!
  • TX power - per your spectrum licence



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