Mic/PTT not working when DAX enabled

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  • Updated 4 years ago

I'm a new Flex 6300 owner in need of help/advice.

I have set my flex nicely to work with my computer and N1MM+ Logger. The CQ WW is approaching fast, so I have configured N1MM+ with voice keying (via DAX), which works beautifully well. 

Using latest SmartSDR (1.5.1), slice 1 configured with DAX1, in mic section DAX is on as well, VOX is on. My headset is plugged into the front of the radio, as well as Mic via heil reduction and footswitch.

So voice via PC works well, pressing F1 in N1MM+ will play the recorded message via DAX. However, I am not able to interrupt the message via PTT/Footswitch, which is not a problem, as I can always pres ESC.

The main and biggest issue I'm having that pressing footswitch does nothing. VOX via headset does nothing. Mic is set to "Mic" and if I turn DAX off in the panel, footswitch works as well as VOX works without any issues. However, if the DAX is enabled, it won't work. 

I would like to have DAX working while being able to use footswitch or VOX the same time. Please, can anyone tell me what I am doing wrong?

Many thanks.

Photo of Oliver


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Posted 4 years ago

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Photo of k3Tim


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I tried this on a 6500.  DaX enabled etc and while the VoX doesn't work the PTT via front panel mic connection did.  One can have DaX enabled and hit the mic PTT button and audio squires out the antenna.

A strange thing - The Flex control can have a button set for MoX (aka. PTT) and in when engaging the transmitter this way, no audio is sent up the antenna.  SO it seems front panel PTT is the way to go but from your post it looks like isn't working for you.  Could be a difference in 6500 Vs 6300 but that is hard to fathom.

ADD: Tried with remote on/off with no difference.

In any case, good luck in finding a fix.


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Tim - W4TME, Customer Experience Manager

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DAX as it is currently implemented was never intended to be part of a voice keyer solution; it is for digital mode program interfacing..  This will change for the better in the upcoming SmartSDR v1.6.x release.
Photo of EA4GLI - 8P9EH - Salvador

EA4GLI - 8P9EH - Salvador

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I was trying to do some recording and playback of audio profiles with Barry this afternoon and I was faced with this issue.

If I press PTT through the Front MIC connector with my foot switch the audio from DAX doesn't get through to the radio. I can talk with the mic and that goes through, and I can see the audio in the TX Stream of DAX from the recording I am trying to play back and I do have DAX enabled in the P/CW tab, but no DAX sound gets send to the radio. If I activate TX through CAT or by clicking MOX on SmartSDR the sound from the DAX TX Stream gets send to the radio. If I click the PTT (footswitch off the front mic faston) the DAX TX Stream cuts off and only my MIC gets transmitted.

This is annoying and definitely not the way it should work.

This was an issue back in ver 1.2 and was supposed to be resolved. Please add it to the bug tracker.
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Barry N1EU

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I can confirm - in SSB, DAX via DAX Audio TX stream doesn't get transmitted if transmit is initiated by PTT (back panel connector in my case) but does get transmitted if transmit is initiated by MOX.  I hope this can get fixed.

73, Barry N1EU
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Same here.
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Ken - NM9P

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If I understand the issue correctly, it may be functioning as designed.  (referring to V. 1.6.17...)

When using a logger with voice keyer, the logger activates TX via a CAT command or virtual serial PTT command through the SmartCAT interface and the audio from the logger is transmitted via the DAX TX AUDIO channel. 

But when the front or rear panel PTT is activated, then the audio input is from whatever is selected as the MIC audio (Mic, BAL, ACC, PC) so the physical PTT overrides the voice keyer audio by connecting the mike to the TX and overriding the DAX TX Audio Channel input.  This keeps your auto CQ from interfering with anything you are trying say on the live mike.

I don't think there is a way for the rig to mix the mike with the DAX input, it must choose one or the other.  it makes that determination based upon the method of PTT.  Hardware PTT = mike input.  Software/CAT PTT = DAX.  And apparently there is an option to activate MOX which allows DAX TX Audio to be the source (if  you are playing a long sound file via DAX TX AUDIO). 

If you set up the logger to initiate TX via CAT command or virtual serial port then it should work properly as a voice keyer with override external mike.  

Or am I missing something you are trying to do? ... like playing a lengthy recording from Audacity via the DAX TX AUDIO input? 

VOX does not work when the DAX button is active.  The rig assumes that your major TX audio is coming from DAX and is only overridden with a hardware PTT from front or rear panel.  Having VOX active would allow unintended noises, coughs, sneezes, yelling at the cat, etc. to interrupt the voice keyer.

This is the way I have experienced working with DAX TX Audio.  I have not tried it with the latest v.1.6.21....

Ken - NM9P
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EA4GLI - 8P9EH - Salvador

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I think that it is a better option to allow me to decide what to inject to my TX signal instead of limiting my options. I can only record one limited time file which resides inside of the Flex radio, so I have to use Audacity to record files that I can then send to a colleague or keep as a memento of a cool DX contact. It is even a good practice to record your own contests.

I want to be able to send an audio file through DAX while I keep my MIC on. 

Ultimately I want to be able to be the one that decides what sends audio and not have my hands tied by the internal logic of SmartSDR.
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Eduardo Carvalho - KC8R

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Here is the link to another post that I have made with the Mic/PTT and voice keyer working without the need to have DAX enabled.


Let me know if that works. 

Eduardo Carvalho, KC8R