DMR - What is it?
W4BUG (Gold Coast Amateur Radio Association) has made a big step for us. We decided to do our part to help in the
advancement of amateur radio by installing and operating a Motorola
DMR repeater for use by the amateur community in our area. It is on the Brand Meister Network. Repeater I.D. 310035
A Motorola DMR repeater is installed at the John Knox Village along with the Icom 146.61 and the Icom 442.500 repeaters that also consists of the CAT800 controller.
It uses the internet to connect to other DMR Talk Groups and in to other repeaters around the world with a little 5 Watt HT.
Surely, most operators are pretty much in the dark as to what DMR really is and what it means to them. This page is an attempt to help explain the system and start you on your way to understanding the system.
DMR (Digital Mobile Radio) is a digital voice and data protocol specification developed for use in Commercial radio but is now being used by amateur radio users.
DMR compatible radios are available on VHF and UHF amateur radio bands but almost all of the DMR stuff is currently on UHF band at this time. In addition to the over-the-air protocol, DMR also provides specifications for network connectivity by using various Talk Groups on one frequency, enabling DMR radios to be connected to the Internet or other networks and repeaters. DMR is based on the Motorola MOTO Turbo type commercial system. (DMARC)
As long as the signal strength is above a minimum threshold, the quality of the data received (AKA Packets)is better than an analog signal at the same strength. It is capable of linking other repeaters together through the Internet by using Talk Groups, so HAMS may talk to other HAMS in a different state or even a different country if so desire.
Another important aspect of DMR technology is its ability to send short messages to emergency responders in the event of a disaster. Disaster Service agencies or even County \ State or Federal agencies can instantly relay and send messages to the people that need the information.
The Gateway control software or C-Bridges are what link the talk groups together through the internet and into other repeaters.Repeaters are not linked but the talk groups are linked via internet by these C-Bridges and into local repeaters which allows for World Wide contacts via a 5 Watt HT. Each state and each Country have their own unique Talk Group numbers that is used. Like our local DMR repeater has its own Talk Group number which is also the repeater I.D. number (W4BUG) 310035.So if I am say in the state of Washington I only need to find a local DMR Repeater and program my radio to the their frequency and use the Talk Group number 310035 on their repeater and it will key up the repeater where I am at and our club repeater by connecting through the internet.
Their are a few different networks out there and they are not all 100% compatible so check to see by looking them up on the internet. The different networks are as follows:
Allstar Brand Meister (Our Club Uses this one TG 310035)
DMARC (Motorola Based)
These are the most used networks.
There are several Different DMR radios out there so do your research and buy a good one and it must be able to do Tier 1 and Tier 2.