RemoteTx can be used to operate in the FT8 mode remotely after a few items are set up. There are 2 main things that need to be done in addition to the normal remote control setup.

  1. An additional virtual audio cable software component needs to be added to the PC to route the sound between the web browser and the WSJT-X program. In the example below a version from is used on a PC running Windows 10.
  2. An additional usb sound card needs to be connected from the RPi to the mic-input and phones-output of the radio. This is so VOX can be used on the radio to control the keying of the radio. It can only be done if the TX audio is entering the radio through the Mic input on the IC-7300. A Mic adapter plug will also need to be obtained or crafted so that the output of the USB audio adapter (3.5mm plug) is connected to the mic pins on the 8 pin mic connector on the front of the radio.
    Preferred USB Audio device: Behringer U-Control UCA202    RCA Cables
    Also Good USB Audio device: U-Green USB Audio   3.5mm Cables (need 2)
    Mic adapter plug:    W2ENY adaptors    or    Heil at HRO
Step by Step PC setup items (Windows 10):
  1. Download and install ‘VB-Audio Cable A&B’ for the suggested donation of 15 $ or €.
  2. Open the sound control panel by typing ‘Change System Sounds’ in the windows search area.
  3. Click on the ‘Playback’ tab.
    Then with a ‘right mouse click’, disable everything except the computer speakers and ‘Speakers-VB-Audio-Cable-A’ and ‘Speakers-VB-Audio-Cable-B’.

  4. With a ‘right mouse click’ make the ‘Speakers-VB-Audio-Cable-A’ both the ‘Default Device’ and the ‘Default Communications Device’.

  5. Click on the ‘Recording’ tab and then with a ‘Right Mouse Click’ disable everything except ‘Stereo Mix’ (if it exists) and Cable-A Output and Cable-B Output.
  6. With a ‘right mouse click’ make ‘Cable-B Ouput’ both the ‘Default Device’ and the ‘Default Communications Device’.


  7. Double click on ‘CABLE-A Output’ to open the ‘CABLE-A Output Properties’ window and then select the ‘Listen’ tab.
    Check the ‘Listen to this device’ and select your speakers as the ‘Play through this device’ choice.
    This will make it so you will hear your signal when you are transmitting.

  8. Close all sound control windows.

  9. In WSJT-X, open the File->Settings menu item window.
    Click on the ‘Radio’ tab and set ‘Rig Control’ to ‘None’ and ‘PTT Method’ to ‘VOX’.

  10. Click the ‘Audio’ tab and set:
    Input: to ‘Cable-A Ouput’
    Output: to ‘Speakers (VB-Audio Cable B)’

    This completes the setup of the sound settings and WSJT-X.
    Next is configuration of the Icom 7300 and RemoteTx.
Icom Physical 7300 Setup:

A USB sound card needs to be connected to the Icom 7300 so that it’s output (green) is connected to the mic pins (1 and 7) of the radio 8 pin mic plug. The USB sound card input (red) needs to be plugged in to the phones jack on the front of the radio. A mic adapter is required similar to the one in the photo below. (Search for ‘Heil AD-1-IC’ on the internet).

RemoteTx Icom 7300 Settings:
  1. Connect to the IC-7300 control interface configure the following items:
    • Set receive filter to ‘Wide’.
    • Turn ‘VOX’ on (button is blue).
    • Set MOD-SOURCE to ‘MIC’.
    • Set TBD to ‘WIDE’.
    • MIC-GAIN about 10 (adjust as necessary).
    • Turn COMP off (button is grey).
    • Set VOX and Anti-VOX at 50.
    • Set VOX-Delay at 0.
    • Set AF-GAIN at about 20 (adjust as necessary).
    See Below:
  2. Select and Start the secondary USB audio sound card.
    • Select the secondary USB sound card. It could be either 0 or 1, just experiment.
    • Click the green ‘Start/Restart’ button.
    • Make sure AGC is not checked if it is present.
    • Click ‘Call Radio’ to start sound.
    See Below:
  3. Start WSJT-X, manually set the band to match the radio.
    You should see signals decoding and when you transmit the radio should transmit via VOX.
    The RemoteTx control interface will show if the radio is in transmit or receive and will show PWR, SWR and ALC.
    Make audio adjustments with the TX Mod setting above and the output level (PWR slider on right) of WSJT-X so that ALC is just beginning to register.
    Make sure ALC is not high. It is best to initially get everything adjusted while you are in front of the radio.


  • Turn off ‘VOX’ when you are done so that it doesn’t start triggering if you later connect to the radio with your phone.
  • Make sure the clock on your PC is recently synced to network time.
  • Reduce the size of the RemoteTx window by changing the zoom factor of the browser.
  • Set WSJT-X so that it automatically prompts you to log completed QSOs.