Settings for: Remote Flex 6400 + Local Maestro C + FreeDV on local computer

W4AFK Bruno

My 6400 is remote and I am using my Maestro via SmartLink and it's working fine. I am getting confusing info regarding the setting when using FreeDV.

• Maestro in client mode
• DAX activated on the computer next to the Maestro
• CAT activated on the same computer
• FreeDV started on that computer

The confusion:

Some say that I need to select DIGU while other say that I need to leave USB.

The typical explanation :

We run keyboard digital modes (FT8, JS8Call, etc.). using DIGU because:

• DIGU bypasses mic processing
• DIGU gives a flat, wide passband
• DIGU expects DAX audio
• DIGU avoids SSB shaping

They say that FreeDV is not a data mode in the Flex ecosystem. It’s a digital voice mode that behaves like a modem‑driven SSB microphone.

They recommend leaving the radio in USB mode

• Mode: USB or LSB (NOT DIGU or DIGL)
  
• MIC Source: DAX
  
• PROC: OFF
  
• TX EQ: OFF
  
• DEXP: OFF
  
• TX Bandwidth: ~100–3000 Hz (not more than 2900 on 60m)
  
• Slice DAX: ON

Now I have tried using DIGU and USB with similar results, But I would like to know what is the proper setup.