no TX from WSJT-X FT8

Michael Wheatley

I have been using WSJT-X v 2.1.2 with modes FT8 & FT4 successfully on my Flex 6400 SSDR v3.1.8 for some time.  I normally start WSJT-X when I start my radio and just leave it run monitoring the band. It works fine for a while, but if I leave SSDR & WSJT-X just sit there running for a couple of hours, when I come back to it and try to transmit (eg: call CQ). WSJt-X keys the radio but there is noting transmitted (no RF output).  If I close and restart WSJT-X it works fin again ... for a while.

I have WSJT-X radio rig set to FlexRadio 6xxxx and the rest of the settings work fine.  Test CAT works fine and PTT is set to CAT.

Has anyone encountered this problem?  Is there a fix?

Michael -- KM6LHD

Wilbur Doolittle

check dax control and see if they are greyed out or asleep per say 

Rich McCabe

N8AUM

Al K0VM

N8AUM

Michael Wheatley

Rich McCabe

Phil Moore M0TZZ

N8AUM

Same with my setup

Ria

This is a long-standing bug in WSJT-X

Rich McCabe

Al K0VM

Tim - W4TME

I have fixed this by deleting or renaming the wsjt-x.ini file and let WSJT-X create a new default file that I re-setup manually.

Arvind Mallya

Tim, can you explain what you mean re-setup manually, do you mean delete WSJTX and reload, reload what? It almost looks like a Windows time out function. If I leave it for a while running it seems to lose the synch with WSJTX. I have to reload it and then works fine

Tim - W4TME

Deleting WSJT-X will not work.  There is a wsjt-x,ini file that resides in the %APPDATA%localWSJT folder ( this is documented in the WSJT-X documentation). 

You rename (preferred) or delete the wsjt-x.ini file and restart WSJT-X.  When you do this a new default wsjt-x.ini file will be created and you have to manually re-enter you call, grid, set up radio control and configure the audio input and output to use DAX RX and DAXT TX respectively.

Harold Rosee

Mark_WS7M

Yes... For me this seems not a WSJT-X issue but rather a DAX issue.  I saw this lack of transmit issue the other day on 80m FT8.  Restarting DAX fixed it for me.

The partner issue for me in this is that even though DAX shows normal actively and looks normal WSJT-X will stop decoding.  A restart of DAX (changing NOTHING else) will get it to start decoding again.

Changing from DAX 1 to 3 helped this some and make it last longer.

Some one mentioned in some thread that when the decoding stops that there is like a high frequency signal superimposed on the DAX audio and it can be seen in the WSJT wide graph.  I can't see it or do not know what I'm looking for.

But restarting DAX fixes it.  It also fixed the lack of transmit issue as well.

Running 3.1.8 on a fairly fresh Windows 10 install.

Tim - W4TME

Note that when you restart DAX, you are also reinitializing the audio interface in WSJT-X (or any connected digital mode application) as well.

N8AUM

Arvind Mallya

I use my Flex 5000A with WSJTX-FT8 never had a problem, once the com ports and Vac are setup it never changes. I also found I can drive it harder and not generate lot of harmonics.

Mark_WS7M

That is understood Tim.  However in my testing when the "DAX Corruption" problem appears, restarting WSJT-X ONLY does not result in reestablishing decode (or perhaps transmit but I have not verified that).

I systematically when the decode issue appears tried the following steps:

1) Confirm time keeper to be accurate and using good sync pool

2) Reconfigure audio in WSJT-X -  Select different DAX, save, Reselect correct DAX save.  No effect. Decode would not continue.

3) Reconfigure audio in WSJT-X to different DAX channel - Change SSDR slice to use new channel.  About 50% success with this.  Sometimes it does not does not restart decode.

4) Restart WSJT-X - No effect.  Decode would not continue

5) Restart DAX - Works every time.  Decode restarts almost immediately and lasts until the next time something in the chain fails.

I have confirmed similar behavior using SSTV program.  Working with a friend who was expecting images I would send he texted me at one point and said the image looked like garbage.  We were both S10 to each other.  He transmitted an image to me and it was full of strange looking noise.

I restarted DAX and resent my image to him and it was crystal clear and same thing on receiving his image.   

I observe this behavior on three different Windows 10 machines.  All are running 3.1.8.  I admit I have only tried the SSTV test on my main shack machine.

I am at this point pretty convinced that DAX has some corruption issue that periodically appears.  The symptom is enough noise usually in the receive audio that it messes up decoding problems.

The transmit or failure to transmit issue seems to be another problem that is fixed by a restart of DAX.   But I have only experienced that one a few times and I have not had the time or chance to do careful analysis of the broken piece.   In the several times this has happened to me, DAX restart did fix it.  Whether it was DAX or WSJT-X I cannot say.

I will say that this corruption issue with DAX receive is bad enough that I don't do much FT8.  I would love to leave FT8 on all day long and let it decode up a storm but my experience is that it will not run that long without human intervention.

Tim - W4TME

If restarting DAX is the key mitigating action, then I suspect that the issue is related to the PC generating excessive DPC latency that is resulting in DAX audio buffer corruption.

Michael Wheatley

Dave - G3SBP

Mark_WS7M

Tim, 

Interesting...  I downloaded a DPC checker and it is showing this one system as marginal.  Sometimes it gets bad.  Not sure what is up but I will dig in further.

I can't test the other system right now but I will try to get to that soon.

One question:  My DPC checker is saying that the system should be "ok" for audio with minor dropouts.  If that is the case why would DAX not recover if the drop out was just momentary?

I get that it could cause problems for some period of time, maybe cause a full FT8 packet to not decode but why would the problem persist?

Michael Wheatley

DPC checker shows no problem on my system

N8AUM

Dave, regarding the "fuzzy" decodes I found that the AGC /gain setting has a great effect. In FT8 or WSPR modes I run with AGC off and than play with the gain settings until I find the sweet spot so both weak and strong signals look clean on WSJT's waterfall and doesn't exceed 60 on it's input level. also dont forget to check DAX output so its not over driving. Hopefully that makes sense ?

Dave - G3SBP

It only goes "fuzzy" when the DAX fails. resetting DAX and all works perfectly but only for five minutes or so before it happens again.
Dave

Dave - G3SBP

Francesco Doenz

After three days of searching and trying all the suggested fixes in the forums, renaming the wsjt-x ini file as suggested by Tim worked for me...but too bad, three days gone crazy....