DAX Audio TX gain settings not saved on Profiles is a problem

  • 1
  • Problem
  • Updated 3 years ago
  • Not a Problem
I like the idea of only one DAX TX channel however using digital programs (WSJT-X, MMTTY, etc.) that don't have the same TX output level need a separate DAX audio gain level setting to get the maximum drive to my radio (6700). This leads to having to reset the DAX TX slider when a different digital program is started, The eight DAX TX channels could have been left alone because you still have to select the DAX TX channel. The Auto Switch TX function would have worked on the Eight channel setup.
Just my two cents worth.
Love My Flex.
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Posted 3 years ago

  • 1
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Alex - DH2ID, Elmer

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Al, I leave DAX audio TX gain at 58, which is my setting for DM780, and
control audio tx for WSJT-X with it's Pwr slider. This works for all programs,
even exotic ones like ROS or SIMPSK.
Alex DH2ID
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Wspr wsjt and others have their own level adj so I can trim them down as needed
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Al K0VM, Elmer

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  For programs that do not have their own TX level control, I find that I can use the Windows Volumn Mixer for DAX Audio TX . 

Or you can set all the TX levels from there... You should note that the control for most app does not show up in the panel until thjey have been in transmit and that rebooting the PC will removed them until they are in TX again.. but the level is reatined.  (Win10-64)

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Tim - W4TME, Customer Experience Manager

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This is classified as technically not a problem because the DAX gain levels are not part of the radio profile.  DAX is a "client side" application, meaning that the settings for it are stored on the client PC.  Profiles are radio settings that are stored in the radio.  So rather than this being a problem, it is really a software feature enhancement (Idea) post.
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OK sorry Tim I should have said that it was a problem for me. Is there write up on how DAX works? For
example does
1 DAX actually take the digital data from the radio (1s and 0s)
2 Or does it use a ADC on the audio output to send the data directly into the digital program
3 Or does it use a ADC on the audio output send the data and use a DAC to feed the data to a program.
Conversely how does it handle data on transmit .
I have been searching the internet for a description of its operation but have not found anything.
The reason I ask is because the input slider on WSJT-X does not seem to make any difference to the output data no matter where it is set, MIN to MAX or anywhere it is set in between. It seems to be a straight digital (1s and 0s) input stream.
73 Al N4AB
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Tim - W4TME, Customer Experience Manager

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DAX is a type of audio protocol formatter.  On receive DAX takes binary audio data streams from the radio (UDP over a network connection) and formats or "presents"  them as a Windows sound device interfaces (aka "sound cards").  These are the DAX channels.  For transmit, binary audio data from a third-party application is sent to a Windows sound card (DAX) interface.  Then is is formatted as a UDP data stream and sent to the radio.  SmartSDR in the radio is responsible for making sure the correct audio stream is associated with the correct slice receiver or panadapter in the case of DAXIQ.

In the radio, the data (audio) is always digital until we convert it to analog to send it out one of the analog outputs on the radio hardware.  We do not do multiple A to D to A conversions of the audio as this degrades the audio quality.

WSJT-X is one of those programs that has a lot of quirky behavior in how it handles audio and serial port control (CAT).  I am not sure why it's audio gain controls are not working as they should.