John's Meanderings

Yaesu Fusion Repeater on D-STAR

The latest setup information is at

I am working on a project over at NW Digital Radio called the Universal Digital Radio Controller or UDRC. The initial purpose of the UDRC is to allow one to convert the Yaesu DR-1X Fusion repeater to operate in a tri-mode fashion;  Fusion Digital, Analog FM, and D-STAR.   While prototyping the UDRC, I have used various GMSK modems for D-STAR including the URI and DVRPTR V1.  The UDRC is undergoing some refinements as we learn more about Yaesu’s plans, as well as making it more general for other projects.  It will probably be a few months before the final product hits the market.


The UDRC is now available.

In the meantime, some people have been asking if it is possible to put D-STAR on the DR-1X without the UDRC.  This is possible without any internal modifications to the repeater and simply requires wiring up a HD-15 (VGA like) connector to the repeater for connection to a GMSK modem / D-STAR adapter.

Preparing the DR-1X Repeater

Setup the repeater as you would for a fixed FM in and fixed FM out analog repeater.


Enable the ‘remote’ function on the controller.



The DR-1X I/O Connector

You will need to obtain a male DB-15 HD plug and cover. If you are just prototyping and don’t want to solder up a connector, I recommend obtaining a breakout board.  I use a Winford Engineering DB15HD Model (Male) with a M-F patch cable to go to the repeater. (Do not use a VGA cable, the lines must be straight through.)


The pins used are:

Pin Function
1 Remote Control Enable
5 Ground
6 Tone / GMSK In
8 Disc / GMSK Out
10 Ground
11 Ext Port 1

Next you will need to decide if you want to run D-STAR only or D-STAR/Analog Dual Mode.

D-STAR Only Mode

DR-1X Pin URI Pin Mini Din-6
1 20 2
2 Ext/GPIO 3
5 DR-1X (1) DR-1X (1)
6 22 1
8 21 4
10 DR-1X (11) DR-1X (11)
11 DR-1X (10) DR-1X (10)
  • Tie Pin 1 and GMSK (Audio – Pin 20 on URI, Pin 2 on Mini Din-6) ground to Pin 5.  This locks the repeater controller out and puts full control to the D-STAR modem/node adapter as the repeater controller.
  • Tie Pin 2 PTT to the PTT control (pull to ground) on your D-STAR modem/node adapter (URI will use an external device like a GPIO on a Raspberry Pi, Pin 3 Mini Din-6)
  • Tie Pin 6 TONE (Modulator) to GMSK OUT from your D-STAR modem/node adapter (Pin 22 on a URI, Pin 1 Mini Din-6).
  • Tie Pin 8 DISC OUT to GMSK IN to your D-STAR modem/node adapter (Pin 21 on a URI, Pin 4 Mini Din-6).
  • Tie Pin 11 to Pin 10.  This tells the repeater to stay in FM in / FM out mode full time.

D-STAR/Analog Mode

DR-1X Pin URI Pin Mini Din-6
1 Ext/GPIO 3
2 Ext/GPIO 3
5 20 2
6 22 1
8 21 4
10 DR-1X (11) DR-1X (11)
11 DR-1X (10) DR-1X (10)
  • Tie Pin 1 Remote Control and 2 PTT to the PTT control (pull to ground) on your D-STAR modem/node adapter (URI will use an external device like a GPIO on a Raspberry Pi, Pin 3 Mini Din-6). This lets the Yaesu repeater controller handle analog when the PTT is high and puts full control to the D-STAR modem/node adapter as the repeater controller when the PTT is low.  Set a CTCSS tone in and out on the Yaesu controller but do not use 100 hz as the GMSK signal will periodically false the tone decoder.
  • Tie Pin 5 and GMSK (Audio – Pin 20 on URI, Pin 2 on Mini Din-6) ground.
  • Tie Pin 6 TONE (Modulator) to GMSK OUT from your D-STAR modem/node adapter (Pin 22 on a URI, Pin 1 Mini Din-6).
  • Tie Pin 8 DISC OUT to GMSK IN to your D-STAR modem/node adapter (Pin 21 on a URI, Pin 4 Mini Din-6).
  • Tie Pin 11 to Pin 10.  This tells the repeater to stay in FM in / FM out mode full time.


Use dstarrepeater and ircDDBGateway from G4KLX to control the repeater and connect to the D-STAR network.  Source for the programs can be found on GitHub.


That’s pretty much it.  You will need to adjust the audio levels on the GMSK modem until the measured deviation is 1.2 KHz. out of the repeater.  This should be 0.8-1.0V (1.6-2.0V in half deviation, NFM) peak to peak on the DR-1X.


GMSK Output

Captured RF Output From DR-1X on D-STAR

G4KLX GMSK Modem through URI

G4KLX GMSK Modem through URI into DR-1X

Also see Converting the Kenwood TKR-820 … For pinout for the NQMHS.

Image of Mini Din-6

Mini Din-6

As always, this information is provided as guidance, please refer to documentation for the repeater, controller, modem, and software to verify correctness.  The author is not liable for any damages based on the information provided herein.


  1. John Leonardelli

    john, thanks for sharing your experimentation and creative work. I cant wait for my local Fusion guys to add a bonus mode to their configuration

  2. The L-com (DGBH15MT1) field termination male connector may work as well for the HD-15 breakout board. MCM Electronics has it for $10.80 plus shipping.

  3. John, that is excellent work. We have a DR-1X repeater installed here, and I am the only person that knows anything about ‘digital comms’. The other club members are ‘afraid’ of digital, and want to keep the repeater in ‘FM/FM’ mode! The more info that I can ‘feed’ them, the better! Thank you for the information…


    Bruce VK2EM
    Greatlakes Radio Club
    New South Wales

  4. Any way to interface this project with an actual icom G2 repeater stack???


    • Terry, I’m not sure how there would be any need.

      The Icom G2 stack can be directly supported by ircDDBGateway, which gives it much more functionality at no cost.

      An Icom D-STAR repeater cannot be used on analog without major modification and there currently is no modification to Yaesu Fusion, though if one did modify the repeater for analog, and got access to both the discriminator and modulator, G4KLX’s mmdvm project could use the RF section to add more modes.

      What are you looking to do?

  5. My DR1X has been running D-Star this way since early May 2015. Was on the air for Hamvention weekend. W9IPA currently located in Dayton, OH. This repeater makes a great Dstar repeater. My interface is the DVRPTR board.


    Best Regards from Germany

    Peter DL3GS

  7. Hey John,

    Just had a quick question about the connections for analog/D-star operations.
    I was looking to connect for dual mode, Is the connection for COS/Squelch not required when connecting to the back port of the DR-1X

    • James,

      That is correct. The use of CTCSS on both input and output by the DR-1X internal controller takes care of the Analog squelch.

      The GMSK modem is looking for the GMSK signal full time and COS isn’t necessary, it only triggers PTT upon detection of the D-STAR signal.


      • Great, thanks for the info John, I will let you know how it works once I get my DVRPTR-V1 board as I don’t want to re adjust my Moen GMSK board to the DR-1X as it is setup for and working in my current setup with two commercial radios.

        Also, Looking forward to the new Tri-Mode setup your working on, Great work and Thanks Again for the quick response.


  8. See updated information on voltage for deviation in the post. The latest DR-1X firmware allows NFM (2.5 Khz deviation). Basically, you double the voltage going to the modulator when in NFM mode.

  9. Hello John,

    Seen the post of UDRC being available very soon, Excited to get one ordered and connected to my repeater. Quick question, I have seen the video and information on the UDRC, just curious is it a stand alone unit? As it stands now I am using a pi2 with a dvrptr-v1 to run analog//D-star, will I still need the dvrptr-v1 in conjunction with the UDRC or will I no longer need the dvrptr-v1 board for running tri mode.


    • K7VE

      19 April 2016 at 15:32

      Hi James,

      The UDRC will be out shortly. It is a hat for a Raspberry Pi 2/3 (40 Pin GPIO). The UDRC connects GPIO pins to the HD-15 (Accessory Connector) to the DR-1X as well as providing the modem for D-STAR. A driver for the sound chip on the UDRC to create the modem and the control logic for switching the repeater modes is integrated with an updated version of dstarrepeater (from G4KLX).

      The sound chip has advanced features and is not included in a standard Raspbian Jesse image, so we provide an update that moves a Jesse image to our Compass Linux Distribution (new kernel, drivers, and other file updates).

      You will no longer need the dvrptr-v1 to provide D-STAR/Analog operation. This is supported by the UDRC on the latest 1.00 version firmware. If you want to also support Fusion Digital (C4FM) you will need to have your firmware updated to the post mid-December 2015 version 1.10D (or later), this will allow you to repeat Analog, Fusion Digital, and D-STAR switching on a per transmission basis.


      • Thank You for the Information John,

        Looking forward to placing my order 🙂

        73 and keep up the good work


  10. Hi John,

    Another quick question as I was curious, Would that setup with the UDRC connected to the DR-1X effect any attempt at connection to an external controller at all?
    Or is that no longer possible once the UDRC is connected.


    • K7VE

      22 April 2016 at 15:07


      It wouldn’t be impossible, but would be very, very difficult and would probably require code changes (the UDRC code is open source).

      If you are looking for some ‘whiz-bang’ feature of an analog controller, you might be out of luck. However, if your main interest is linking to another system, then using RF is probably the best approach. That’s how WIRES-X will interconnect and could be done with other systems.

      — John

  11. Hi John,
    please let me know to place an order
    Best regards from Germany
    Peter DL3GS

  12. John, I’m not sure if I understand how to setup this D-Star on the DR-1, but I’m just starting to learn this.

    So I need the 15-wire-cable to connect the DR-1 to an URI or DVRPTR-modem, is there any difference which of these two I would use?

    The two programs, you say there is only source code available. How do I compile this (does it need to be compiled)? Which software needs to be loaded to which device?

    How do I physically connect to the D-Star-network, is it Ethernet from my router to the DR-1?

    BR, Pat.

    • K7VE

      17 May 2016 at 09:55


      When I wrote this blog post there wasn’t an integrated solution, now there is one here. The post is meant to provide the basic information to accomplish D-STAR on the DR-1X.

      With the UDRC, there are pre-built packages for dstarrepeater and ircddbgateway that perform all of the arbitration of D-STAR, Fusion Digital, and Analog through the repeater. The Raspberry Pi provides the Ethernet (or WiFi) to connect back to the D-STAR network over the Internet.

      One can build up a solution, using a DVRPTR-1, URI, Sound Card, etc. and cabling up to the GPIO pins, but the UDRC makes it easy. You can order it at


      • Thanks for the quick reply, John. Good to see that the UDRC is available, and the price is fine, too.

        But I still have some questions:

        This UDRC offers two connectors, 6-pin and 15-pin, which one do I need to connect to the DR-1? A 15 wire cable can be connected one-on-one? Except for a brief data sheet and a photo I have not found any more information about this device.

        Having a Raspberry Pi with Debian, I “just” need to load the two pieces of software? Or do I need a compiler software, too? I’m not familiar with Linux at all.

        Is there any information what these two programs will do, and how to setup, how to operate them? Github is no help at all, it is hardly usable. When searching for the program names, it just gives you unusable code snippets. I have no idea how to download there anything, and how to find documentation there. This seems to be for nerds only, not for normal persons 🙁

        BR, Pat.

        • K7VE

          18 May 2016 at 10:30


          We are all getting ready for the Hamvention. After the weekend, there will be more information.

          If you order the UDRC with the HD-15 cable, that is a direct plug in to the repeater accessory jack on the DR-1X (This is the model we have developed and tested with).

          You will put the latest Raspbian Jesse on an SD Card and run a script that updates it to Compass Linux Kernel (it’s Jesse with support for the advanced audio CODEC on the UDRC). Then a couple of commands to install ircddbgateway and dstarrepeater. This will all be documented.

          General configuration of ircddbgateway and dstarrepeater is covered in their support forums (on Yahoo!) in the files section — we will provide ‘seed/example’ configuration files, which you can edit by hand or by using the graphical tools ircddbgatewayconfig and dstarrepeaterconfig.

          There will also be a preloaded SD card with an image from NW Digital Radio.

          73, John

  13. Hi w7qa I have a question? Our little club bought a dr1x repeater, the Urdu an a pi 3. We are attempting to install the Urdu. We configured it from your YouTube video. That’s where we got stuck.

    Major question is first with the repeater in fixed fixed do we loose the digital use of the repeater? We are trying to wrap our heads around how this all works.

    We have id 5100 mobiles an ftm 400 is it possible to use both with this setup?

    We are a little confused, can someone shed some light for us please.

  14. John. We have a dr1x running with a dvrptr1 and it is about 1.5 years old. At present I don’t know the firmware version. Do you know if the dr1x will receive using narrow band filters in FM mode with the new firmware that has selectable wide/narrow band. I am assuming we are receiving using wide band filters presently. I have personally seen that narowband receivers work much better with dstar that wideband receivers. Your feedback would most helpful. Thanks
    Tem Moore

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