Last edited · 64 revisions  


Datasheet: UDRCDS


Important: Use only Compass Linux images and dstarrepeater packages.  They contain support specific to the UDRC™. Source is available for review on GitHub.

Mount your UDRC™ on a Raspberry Pi 2 or 3

Make sure the pins are properly aligned and use the supplied standoffs to support the board above the HDMI port.

Universal Digital Radio Controller Universal Digital Radio Controller

ircDDB Registration

Now is a good time to register a unique callsign for your repeater at  In the United States this needs to be a club callsign, in other countries a secondary callsign is necessary.  If you want to use your personal call sign, you will be able to run the repeater and perform linking to repeaters and reflectors, but will be unable to do callsign routing including STARnet Digital groups. If you already have an ircddbgateway registered, you can just add this repeater to it at configuration.

Create the Boot Image

  1. Obtain a high quality microSD card.  A Class-10 card of 8GB or more is recommended.
  2. Download a Compass Linux image from
  3. The 'lite' version is without a GUI and will require hand editing of the dstarrepeater configuration file.  The full version has graphic configuration tools for those new to setting up dstarrepeater and ircddbgateway.
  4. Unzip and copy the uncompressed image to the SD card using the procedure outlined on the Raspberry Pi site.

Boot for the First Time

  1. Place the microSD card in the Raspberry Pi.
  2. Attach a monitor and keyboard/mouse to the Raspberry Pi
  3. Attach Ethernet via the RJ-45 jack to your network.
  4. Apply power via one of these methods
    1. Using the microUSB port next to the HDMI port (good if you are not at the repeater site)
    2. Through the 15-Pin connector while attached to the DR-1X repeater (Power down the repeater while installing the supplied 15-Pin cable)
  5. Allow the Raspberry Pi to boot up
  6. Login  (User: pi, Password: raspberry)
  7. From a terminal command line, verify that the UDRC™ is recognized by typing the command aplay -l (that's a lowercase l) and observe that udrc is listed as a card.  If you do not see it listed, power down and remount the UDRC™.
  8. Perform any Linux configuration specific to your installation, e.g. assign specific network addresses, install favorite tools, etc. (This is beyond the scope of NW Digital Radio support, please use Linux support resources for assistance.)
  9. You may wish to edit the /etc/hosts file and add reference to the hostname, for example if you keep the default 'compass' hostname, add a line    compass
    If you want to change the computer hostname use the command
    sudo raspi-config
    Then select "Advanced Options" -> "Hostname" and follow the instructions.  It will update the hostname for your Raspberry Pi and will make the change in /etc/hosts
  10. To preset the pins and levels on the UDRC™ we provide a script.  Execute the following:
    curl -L -s | sudo sh
    (the 'pipe' or | is usually above the \ key on most keyboards -- if you want to see what the script does, leave off  '| sudo sh')
  11. To gracefully shutdown the Raspberry Pi, you may use the command sudo halt

Install Applications

You may install any mix of GUI and non-GUI versions of the repeater and gateway software. Use the following commands on the command line. For GUI tools: sudo apt-get install dstarrepeater ircddbgateway For non-GUI tools: sudo apt-get install dstarrepeaterd ircddbgatewayd (If you are running ircddbgateway on another computer, there is no need to install it on the Pi. You will configure dstarrepeater to access the ircddbgateway.)

Configuration of dstarrepeater

Download the seed file for the dstarrepeater

sudo curl -L -s -o /etc/opendv/dstarrepeater_1

If using the GUI install, you can edit the file with:

sudo -u opendv dstarrepeaterconfig 1

If non-GUI, use an editor like nano or vi to edit, e.g.

sudo nano /etc/opendv/dstarrepeater_1

You will need to change the repeater callsign and gateway callsign to your system.  If you are doing a 70cm repeater these are the only settings that need changed for initial configuration.  Only adjust other settings if you understand their effect.

If you are using a 2 meter configuration, you will need to change the Sound Card Modem RX to 0 or not inverted.

The repeater will switch to D-STAR upon receiving D-STAR traffic and return to the configuration set for the UDRC™ (serialConfig in dstarrepeater_1)
Config Choices are
1  Auto RX / Fixed FM TX
2 Auto RX / Auto TX  (Defaulted in seed file)
3 Fusion Digital Fixed RX / Fusion Digital Fixed TX
4 Fixed FM RX / Fixed FM TX (Use this if you are not on DR-1X firmware 1.10D or 1.10J)

Starting dstarrepeater

The repeater must be set for remote mode and a CTCSS should be active on input and output.

Be sure to use CTCSS on RX/TX in analog, avoid 100.0 Hz as that can false on a GMSK signal.  User radios should use CTCSS squelch (DCS should work as well, as confirmed by Ken - N1DOT).  Also, you should recommend to your users to activate BCLO (Busy Channel Lock Out) on their radios to help avoid stepping on transmissions in a different mode.

If you powered the Raspberry Pi using the micro USB port, shutdown and remove the USB cable.

Make sure the UDRC™ is connected to the DR-1X using the provided 15 pin cable.  This should power up the Raspberry Pi.

NOTE: Many standard VGA Cables do not have all of the pins wired and will not work!

Login to the Raspberry Pi and issue the command:

sudo systemctl start dstarrepeaterd@1

The repeater should now repeat D-STAR signals received on the repeater's input. Test by keying up and watching the D-STAR radio's display.

The code gives preference to local traffic over D-STAR network traffic, regardless of mode.
If you want to run WIRES-X use a separate node radio attached to the HRI-200.  You cannot use the HD-15 and mini DIN-10 at the same time.

If you want to see a GUI, run the commands:

sudo systemctl stop dstarrepeaterd@1

sudo dstarrepeater 1

Logs for troubleshooting are at /var/log/opendv

If you want the dstarrepeaterd daemon to start on reboot, issue the command:

sudo systemctl enable dstarrepeaterd@1


Since there are no special instructions for ircDDBGateway for the UDRC™, please refer to the documentation in the files section of the Yahoo Group ircDDBGateway If you would like a web based dashboard for ircDDBGateway, check out the real time dashboard at ircNodeDashboard

Support Group

NW Digital Radio is in the process of setting up various community groups at Please create a personal account at Join the main NW Digital group by sending an email from your registered email account to and then send an email to Please use the group for questions and to share your experiences, so that all UDRC™ users can benefit from the replies.