Hi, I’ve been trying to make my Digirig+truSDX work on VARA HF Winlink, but had been unsuccessful so far. The issue is which radio should I use for the settings. If I use Kenwood Amateur or Kenwood TS590S radio models as in the truSDX forums, the radio goes into TX mode immediately when I open a session of VARA HF. Not sure now which radio model to use.
Here is my VARA HF radio settings:
If you only have audio cable connected then radio selection (CAT) should be set to “none”.
The important part is PTT configuration which should be set to RTS of Digirig’s serial port.
Unfortunately, there is no “none” option for Radio Model selection. The closest there is “Manual”.
For the PTT port, would “External” be correct?
Nope that didn’t work either 
I posted my response in another thread:
Rather than set Control Port, set PTT Port parameters, as I have shown in the previous linked post. Good luck!
73 Constrainted
With digirig:
Without digirig:
At this point, I am using digirig with my TruSDX and considering the usb cable-only option a backup for when I smash my digirig cable in the pelican case lid again (ugh!)
The usb only option unlocks some really cool features, like seeing the wattage output and SWR, but it just isnt stable enough yet I dont think. And its currently not being supported by them for that reason. The cat control driver even drops out when using a digirig too, but seemingly less often. I think I might try to figure out some settings to bypass CAT and just trigger PTT with the digirig. I can set the frequency by hand if it means greater reliability.
Hey I know this is an old thread now, but I put my settings for using the digirig with a trusdx at the end of this video:
Thanks for the video. The insights into the evolution of your served agency is a major bonus!
Thanks for addressing the Ref Freq. issue. I like your approach, but two of my truSDXs have been so far off that I use one of the WWV frequencies for a first pass adjustment.
73 Constrainted
Nice! I didn’t think to use WWV!