WSJT-X – FT8

Remote SDR can be interfaced with digital processing software like WSJT-X to make FT8 transmissions for example. WSJT-X not only processes transmit and receive audio signals, but can control Remote-SDR frequency and transmit on/off.

VB virtual audio cable

To interface the audio signals between WSJT-X and Remote SDR, the most elegant solution is to put a virtual cable between the 2 applications on the condition that they run on the same PC.

If you do not have “VB Cable – Virtual Audio Device”, go to the site:
https://vb-audio.com/Cable/
download and install the VBCABLE_Driver_Pack43.zip application

Omnirig control interface

To pass the order of transmission or reception, as well as the working frequency, we use the Omnirig interface available in WSJT-X and Remote SDR.
https://f1atb.fr/index.php/2022/01/18/omnirig-remote-sdr-2/

WSJT-X Setup

Go to File/Settings and select the Audio tab.

Set audio input and output channels i.e. VB-Audio cable.

In the Radio tab, select Omnirig 1 or 2 and the PTT by CAT method.

Remote SDR Setup

On the receiver side, select the direct auxiliary output without filtering and the VB audio cable. Adjust the level by watching the indicator in WSJT-X so as not to saturate.

On the transmit side, also select the auxiliary input via the “VB audio cable”. Press “Tune” in WSJT-X to switch to transmit and adjust the level to maximum at the edge of the spectrum in red.

Remote SDR automatically detects messages from Omnirig. A green Omnirig light at the top is displayed when messages arrive.