Beginners Guide to Digital Mobile Radio (DMR)


DMR in the UK continues to evolve at a fairly rapid rate with many new repeaters and changes in Talkgroups. There are now a number of competing DMR Networks in the UK. The UK has broken away from the DMR-MARC (the original American Network) due to the restrictions and limitations that DMR-MARC impose for membership of their network. The 'Phoenix' network superseded DMR-MARC, offering similar functionality but with more local control. However, similar restrictions imposed by Phoenix have lead to many UK DMR repeaters changing to the Dutch 'Brandmeister' network which allows almost limitless customisation and more importantly allows the use of local 'hotspots' so that the network can be accessed without the use of a land-based repeater.

Summary:

  • DMR This is the Brandmeister 'breakaway' DMR network. The Brandmeister network was developed in the Netherlands and continental Europe and allowed the connection of RF Internet hotspots (see below) giving almost unlimited access to the network even for those not in range of a land-based repeater.
  • DMR+ This the 'original' American lead DMR-MARC network that was established in the UK following the guidelines and restrictions of the Motorola Amateur Radio Club (MARC). Responsibility for running the UK side of the network was taken over by the Phoenix group of amateurs. This network is commonly referred to as DMR+ but is also known as the Phoenix network. DMR+ allows limited connection to DMR 'dongles' and devices i.e. short-range RF hotspots that access the network via the Internet.
  • Although the DMR and DMR+ networks list similar talk groups (channels) the networks are completely separate and it's not possible to communicate from one to the other.
  • Notwithstanding any of the above, various links between networks and even digital modes do exist, and the DMR system as a whole continues to evolve.


See the BlueDV for DMR and DSTAR guide for more details regarding hotspots.

Also, a number of local networks have evolved to meet the needs of local users without the limitations imposed by joining a larger nationwide or worldwide network. Such local networks consist of a small number of DMR repeaters offering just 2 channels or 'Talkgroups', one for working the single repeater and one for working all the repeaters in the local network.

Due to the rapidly evolving DMR system, this webpage will inevitably be out of date! Google is your friend here as there are many forums, websites and Facebook groups with active discussions on the current state of DMR in the UK.

Digital Mobile Radio or DMR is an exciting and rapidly expanding worldwide digital radio system that has been developed entirely by radio amateurs and receives no backing from the usual radio manufacturers. It should be noted that the current digital systems DSTAR (Icom), Fusion (Yaesu) and DMR (amateur support only) use different protocols and are mutually incompatible. However, the number of DMR repeaters is expanding rapidly so if you are not yet in range of one, you might be very soon!

DMR Diagram

  • The DMR Network consists of VHF and UHF repeaters connected to the Internet
  • All but one of the UK repeaters operate on UHF 70cms
  • Access to a DMR repeater is essential to make full use of the system
  • Each repeater has 2 digital ‘time slots’ which means that 2 QSO’s can be conducted at the same time, totally independent of each other.
  • Each time slot has a number of ‘talk groups’
  • The talk groups allow worldwide, regional or local QSO’s to be conducted.
  • Select the talk group you wish to speak on and transmit

There are a number of ‘flavours’ of DMR.

The UK has broken away from the USA based DMR-MARC organisation and has established its own C-Bridge that connects the DMR repeaters to the worldwide network. This allows much more flexibility within the UK whilst still allowing worldwide contacts. The UK DMR network has been named 'Phoenix' to signify that it is separate from DMR-MARC

The DMR-Plus network is less strictly controlled and allows non-Motorola equipment to be used within the network. Hytera equipment is a popular choice for the repeaters and is less expensive than the equivalent Motorola kit. Also, the DMR-Plus network allows cross-network connections (e.g. to DSTAR) and it is expected that it will soon be possible to create a local hotspot to get into the DMR-Plus network if you are not within repeater coverage.

A more recent development is the adoption of the Dutch Brandmeister network system which allows the use of local 'hotspots' to access the network without the requirement for a land-based repeater.

There are also smaller ‘stand alone’ DMR networks, that are not linked to the world wide DMR network but are geographically linked to provide a more regional experience. An example is the SALOP (Shropshire) Net which currently consists of 2 repeaters GB7GT (Ludlow) and GB7BX (Much Wenlock). Such nets are not linked to the world wide DMR network, and use a much simpler system of talkgroups. See the SALOP Net website for further information.

Just to reiterate, it doesn’t matter what DMR radio you have, it can be used on any DMR network providing you are in range of the appropriate repeater - unless you have a local hotspot and then you can access the Brandmeister network anywhere you can access the Internet.


Motorola DP3600

Motorola DP3600

Motorola DP3400

Motorola DP3400

Motorola DM4600

Motorola DM4600

CSI CS700

CSI CS700/CS701


The DMR system is based on a commercial digital standard and as such, differs from normal analogue equivalents in two important ways.

Firstly, in order to access the network and all of its features, the equipment has to be set up correctly using the appropriate manufacturer software and interface. If you purchase from an established radio dealer the radio will almost certainly come programmed with a ‘code plug’, however, there is no guarantee that the code plug will be 100% correct for your area. It is well within the capability of an experienced user to program their own gear, but DMRUK recommends that initially, the repeater keeper or someone nominated by him/her provides this service, This avoids any non-compatibility problems both to the individual and to the network.

Secondly, in order to program your radio, DMR-MARC will provide you with a unique identification number. Further information is available here -  http://register.ham-digital.net


So you’ve read all about how great DMR is and have gone out and purchased a CSI CS700 UHF handheld. You get it home, charge it up and turn it on. It bleeps at you and you try pressing the keypad buttons and it bleeps some more. You know that it’s come from the dealer ‘programmed’ but how the heck do you tune it to your local DMR and Analog repeaters? This is a very ‘quick and dirty’ video to get you started. The menu system is very similar to the Motorola DMR radios, so if you can use the CS700 then you will be able to use a Motorola handheld too. Do bear in mind that just because the radio is pre-programmed, it doesn’t mean that the programming file (code plug) is actually correct as unless the dealer you purchased it from is just down the road, it won’t have been tested in ‘anger.’



As the DMR system is still evolving, you are going to have to get up close and personal with the Customer Programming Software (CPS). Although your radio will be programmed by the dealer, there is no guarantee that the code plug program file is 100% correct, so you will need to edit it. The nature of DMR radios, being based on those used mostly by non-radio specialists, means that it’s impossible to programme channels and frequencies using the keypad. You can change zones (groups of channels) and channels, but these must have been programmed in using the CPS. This excellent video produced by Mike K0NGA so it discusses setting up for the USA, however, it shows very well how the software works and explains contacts, zones and channels.

The CSI programming software is free, but it’s not without its annoying shortcomings. You can’t copy and paste and if you delete any of the ‘digital contacts’ the channels need relinking to the talk groups - no such thing as a free lunch etc - hi

The motorola CPS is much more user friendly, but it’s expensive, difficult to get hold of, the programming leads are not cheap and the radios are more expensive - making the CS700 a good starting point unless you have a friend with the Motorola CPS, program leads and the knowledge how to use them!