Raspberry Pi 3B & RedNode V2.0

ClearNode UHF Transceiver

Your ClearNode UHF transceiver was pre-configured with Tx and Rx frequency 433.500 and CTCSS 107.2. (There is a VHF option.)

If you receive interference on this frequency (Blue LED intermittently flashing) – you should reconfigure these settings to a frequency in the appropriate simplex band that is free of interference.

You should always use an Rx CTCSS code – this prevents your node propagating interference on to the AllStar or Echolink networks.

Understanding the LED Indicators

On the RedNode PCB

Green LED – Indicates the status of the integrated USB sound circuit. When it is flashing it indicates that the USB circuit has been recognized and initialized by the sound software driver. During boot, reboot and power down it will cycle through off, solid and flashing. During normal operation is should be continuously flashing.


  • During power-up and software startup it should flash 6 times to indicate a successful connection to the Internet
  • When it is solid red it indicates that there is no active internet connection – in this condition it is waiting for you to plug in the Ethernet network cable and reboot, or configure a WiFi connection. Once the LED comes on solid red, it will wait for 2 minutes for you to take action, after that it will reboot and try again … and again, and again …
  • Flashes 3 times – this is the indication during normal control operations that a process has completed successfully. For example, at the end of a successful WiFiByLight session it will flash 3 time to indicate proper completion. If you initiate a reboot from the mobile app, it will flash 3 times and then reboot, etc …

Since the release of RedNode API 54 the number of times ClearNode will reboot and try the internet connection then WiFiByLight is limited to 3. After the 3rd attempt it will go into an idle state with the Red LED continuously flashing – 3 seconds on and 3 seconds off. This is to allow you to plug in a monitor and keyboard and login at the command prompt. Sometimes ClearNode receives an IP address (it will announce it over the radio at boot) but the network connection cannot reach the internet – in this state you can use SSH to reach ClearNode on port 22 using the “root” user and your ClearNode Key as the password. To restart the process power-cycle your ClearNode.

Yellow LED – When this LED is illuminated solid yellow (during normal operations after boot/startup is complete) – ClearNode is receiving traffic from the AllStar or Echolink systems and is transmitting that traffic over the embedded radio. Listen for the traffic on your properly tuned HT.

Blue LED – When this LED is illuminated solid blue ClearNode is receiving traffic from the embedded radio. Pressing the PTT on your properly tuned HT will illuminate this LED. If you have connected your AllStar or Echolink to another node or hub – this traffic will be sent to that node or hub. In other words, when this LED is illuminated your voice is being sent from your HT to the AllStar and/or Echolink systems.

If you observe occasional short or longer blue flashes at times when you are not actively using the ClearNode, this is an indication that the embedded radio is receiving UHF interference from some source. This can happen for a lot of reasons, especially since Amateur Radio is a secondary user of the UHF frequencies – in certain geographic locations this interference might be being generated by Military and Defense installations. This is why it is critical that the radio is ALWAYS configured with a CTCSS sub-audio code – this will prevent the interference being propagated onto the Allstar and Echolink systems.

LEDs close to the SD Card

Red LED – When ClearNode is powered it should be on continuously. If you see this LED flashing from time to time it is an indication that the Raspberry Pi board is experiencing and under-volt condition. This is abnormal and should be resolved. Using the plug-in power supply provided with your ClearNode, you should not see this condition, unless you have plugged in USB accessories that are drawing significant current from the power rail.

Green LED – This is the SD Card activity light – it is normal for it flash at any time the ClearNode is powered (wait for this light to go out and stay out to indicate power down is complete, ready for power to be unplugged).