Configuring WSJT-X and SmartSDR for Windows

By Steve, N5AC
Images provided by Jay, NO5J

Think of the DAX Control Panel as a middleman that connects your radio to your digital mode software (WSJT-X in this case). First, we'll get the receive audio path running. In the radio, you need to send the audio to DAX. To do this, pick the slice you want to run digital modes with and select the first DAX channel. You do this in the DAX drop-down on the slice flag. Just pick "1":

 Now you should look at the DAX Control Panel and be sure it is receiving the signal from the radio. Ensure that DAX has channel 1 turned on (the 1 button is blue -- if not press it so that it is blue). You should see the audio meter in the DAX control panel light up (red line showing a signal) and the channel state is Streaming. If you do not see this, you do not have receive audio from the radio getting to the computer. Nothing will work until you have this part working, so it must be right. If it is not, you can try turning the channel off/on to ensure it is connected to the radio and verify that you have the right channel selected in the SmartSDR GUI as shown above. Once you get the signal in the DAX Control Panel as shown below, you are 25% there!


Next, you should go into WSJT-X and ensure that it is setup correctly. Go to the Setup Configuration page in WSJT-X. Here's how mine is setup:

The General tab setup

 The Radio tab setup 

NOTE: Select the TS-2000 as the rig for CAT.

The Audio tab setup

Once you have this done, you should click OK and then go look at the waterfall in WSJT-X. You should see that you have audio from the radio and WSJT-X should start decoding. Note how the waterfall in WJT-X reflects your receive filter in SmartSDR:

 Here's decoding happening now:

Again, if you do not see this -- it must be fixed before you go any further. Now much of the JT-9 activity happens above the typical filter bandwidth of 2900/3100Hz. I recommend grabbing the right edge of the slice receive filter in SmartSDR and raising it to 5kHz or greater -- this way you will get everything over in WSJT-X, even the guys that are camped up at 3500-4000Hz away from the calling frequency. Here's my filter after the change:

 and WSJT-X after the change:

You are halfway there! If you also set up the transmit side in WSJT-X when we had the control panel open earlier, WSJT-X should send signals to the DAX Control Panel and you should be able to see that. To check this, be sure you have a dummy load or your power turned all the way down in SmartSDR and click the TUNE button in WSJT-X. I've shown it here next to the DAX Control Panel:

WSJT-X will go into tune mode and the DAX Control Panel will show audio in the TX gain meter on the DAX control panel for channel #1 and the channel state is Transmitting. Turn down the DAX TX Gain slider until the audio level is just below the 0 indication as shown above. If you do not see the red signal line in the DAX control panel, you have to fix this before going on! Next click the TX button if it is not red in the DAX control panel.

If you have CAT working correctly, the TUNE in WSJT-X also keyed your radio. If it did not, you need to fix CAT before going on! If it doesn't work, verify the settings in both CAT (right click the CAT icon in the Windows System Tray and say "Show" and then check the settings). If this is all working, you are 75% done!

Now go into SmartSDR and ensure you have DAX checked as the audio source as shown here:

Your SmartSDR panel may look different from mine, but the important thing is that you have DAX checked (blue).

Now try the TUNE from WSJT-X again with your power turned down in SmartSDR. You want to be sure you have signal making it to SmartSDR and you will see this with the peak audio level indicator (the far right hand bar). You want to ensure that the signal is peaking just below the 0dB point in the meter -- you make the adjustment with the TX Gain slider in the DAX Control Panel. Your 0dB point may be in a different place than mine, here, so look carefully.

You are now 100% complete. The audio goes from the radio to the digital program and all the way back to the radio and we're keying the radio with CAT. You are now ready to make a contact on the air!

Have more questions? Submit a request


  • 0
    Bill Barrett (W2PKY)

    DAX Contrrol Panel is accessed by clicking on the "Hidden ICONS" triangle shaped ICON in the task tray. Bottom right hand side of the screen.

  • 0
    Larry LaVaseur

    What I found with setting up WSJT-X is that you need to restart it then make the change, you can have the settings correct and it wont work unless you restart the program before making a change.

Please sign in to leave a comment.
Powered by Zendesk