The Midlands Digital Repeater Group (MDRG) represents a group of individuals who not only have a passion and enthusiasm for the D-Star mode, but around the infrastructure for and potential intelligence of the mode. This ethos is best demonstrated by the initial project undertaken by the team to not only understand and provide a D-Star repeater system, but to build a completely new type of D-Star interface that utilises traditional analogue base station / repeater radios.
Beyond this, we are embracing one of the first big benefits of D-Star in that we can more easily create a cellular D-Star environment whereby users are "handed off" from one repeater to another as they travel through an area. While not rocket science, this project
pushes the boundaries of amateur radio knowledge and technology which encompasses RF planning, RF engineering, antenna system design, TRX optimisation, GMSK interface design, development and integration, PC systems design, software architecture, advanced networking, systems integration... the list goes on!
This is an ambitious project, and certainly not one that can be achieved overnight. For many, the D-Star interface for analogue repeaters is a significant enough step but in our context merely provides the development tools for the bigger task!
This website will remain the definitive place to find information and updates as our project develops. Already the project has received assistance by literally dozens of individuals, groups, companies and regulators.
If you have any questions, comments or suggestions relating to the information on this website then please feel free to contact the group: info@mdrg.org.uk and we'll do our best to help.
Don't forget that D-Star is a brand new mode for us and there is much to learn. In many respects you simply have to forget everything you know about analogue because it cannot be applied to GMSK (the D-Star underlying transport protocol). This applies to propagation, coverage, mobile work, fading, antenna diversity, lift conditions and their effects... you get the idea!
The GB7IP 'network' of D-Star repeaters provides transparent coverage from North Birmingham to Stoke-on-Trent and many parts of the M6 corridor through our own analogue repeater interface design and underlying backbone network that allows multiple TX and RX on the same frequency pairs to form a wide area system.
In this implementation three sites (Cannock, Stafford and nr Norbury) provide wide area access for our trial system which when fully developed and proven will result in many of these systems being constructed by other groups.