Jonathan Naylor, G4KLX's software (sound card/FOB) based D-Star Software

A collection of Open Digital Voice software for Amateur Radio based on Jonathan Naylor's G4KLX various projects:

Jonathan Naylor, G4KLX started developing GPL'ed D-Star software in January 2009.

"This group is dedicated to discussing and sharing information about implementing D-Star systems using non Icom D-Star hardware, this includes end user and repeater systems, hardware and software."

His first development (the Digital Voice package) was a GUI Linux client that would decode and generate GMSK using a soundcard and interface to a radio with a 9600 Baud packet connector. The Codec processing would is done by interfacing with a DV-Dongle.  Its design was to emulate a D-Star capable radio.

You can see this in action here:

Local copy from the dstar_development group:


In 2016 David, PA7LIM created BlueDV in 2016, which added DMR and Fusion.  This is an updated client/user end very much similar in functionality to Jonathan's program.  The downside however is that David's project is closed source.

In June 2009, Jonathan G4KLX created a whole new yahoo group for his Analogue and D-Star Repeater controller software.  And in September 2009, he made announcement of a successful test of the D-Star controller:

"This group is intended for people using or intending to use a PC to control their repeater. Initially the controller will be for an analogue repeater, but later versions will include a D-Star repeater, and eventually a mixed mode controller. The source code and support will be available via this group."

The D-Star repeater controller is able to speak to the Open G2 gateway and Dextra reflectors to allow routing and linking to other D-Star repeater around the world. From the perspective of the user it operates the same as an Icom repeater.

He later partnered development with Scott, KI4LKF.  Scott had developed  an "Open G2" protocol.  Jonathan started adding linking support based on this.

When Scott disappeared from development, a team of enterprising German ham morphed the Open G2 and developed the ircDDB.  This add-on Java software allows routing to function between US-TRUST and non-TRUST users, using  the “irc” (Internet Relay Chat) protocol to share data.

Having experience, Jonathan, G4KLX joined the ircDDB team.  He helped the project take one of biggest steps forward co-developing the ircDDB Gateway software.  This offers a very easy way to set up a gateway on nearly all usual hardware platforms regardless if Linux or Windows is preferred.

November 2010

His refined package; G4KLX's ircDDB gateway

With the ircDDB gateway you get callsign routing with quick updates both to and from USROOT connected systems as well as non-USROOT systems. This software can be run on Windows or Linux.

The gateway also includes an APRS interface so that D-Star radios with GPS-A mode enabled, can have their location sent to the APRS network.

G4KLX ircDDB Gateway Installation on Linux   

G4KLX ircDDB Gateway Installation on Windows

September 2015

Hi Folks

I have created a Yahoo group for the MMDVM, this is my introductory message to it. Nothing has been released yet.

The Multi-Mode Digital Voice Modem is a combined hardware and software development of a modem to handle all amateur digital voice modes. Initially it will support D-Star and DMR, with System Fusion and P.25 coming later, as well as a built-in FM repeater controller. For all modes other than DMR and FM, the modem can be used in simplex or duplex mode, while for DMR and FM full duplex must be used. The protocol between the modem and the host is new.

The hardware will typically be ARM based, with initial developments being aimed at the Arduino Due and Teensy 3.1, the STM32 range is also looking like a suitable chip, with the more advanced Cortex M4 architecture and higher clock speeds. The interfacing hardware will consist of op-amp low pass filters and level shifters.

There are no time scales for the release of hardware or software as all development is done in my spare time and there is a lot to do.

If you have any experience of ARM (or any other decent embedded CPU), you are welcome to take part.

Jonathan G4KLX

Jonathan has also published these useful documents:

Slow Data.pdf The Format of D-Star Slow Data Version 0.2 by Jonathan Naylor, G4KLX

Towards an Open D-Star Reflector System - A new D-Star Reflector system.


For more information and/or to obtain any of the software he as written, visit the corresponding yahoo groups.

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