"QRN" on transmit?

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  • Updated 2 years ago
Last night operating PSK with my digital profile and using Monitor, I periodically heard sounds like static crashes on my transmit audio.  They were very obvious on my transmitted waveform also.  

Listening carefully on receive I heard them in addition to normal atmospheric noise.  Went to a dummy load and they were still there on receive and transmit.  It was the same kind of random "static crashes" that you get with a dirty volume control pot or failing audio circuits.  I rebooted the computer and they went away.  Not completely understanding how DAX works, anyone have any ideas as to the source?  
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Dick B

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Posted 2 years ago

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Rory - N6OIL

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I also get those when doing JT modes, if I stop and start the DAX and CAT control w/SSDR it will go away. I leave my system up 24/7, my thoughts it's a memory issue. It hasn't caused me any decode errors on the other end. Next week I'll try to capture it.
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Bill W2PKY

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FRS is aware of the problem. Corruption of the transmit channel has been an issue for ever when running the software for extended periods of time. My system is on 24X7 as well with multiple WSJT-X instances running. Best advice is to recycle DAX when contemplating transmitting if DAX has been on for many hours.
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Andy M5ZAP

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Again a documented list of known issues would help everybody. Why the reluctance by Flex to list all known issues along with if there is a temporary workaround.
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NM1W

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I sure wish flex would address the corruption issue....
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Cal Spreitzer

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+1 on Flex addressing this!  I've had the issue happen using the latest SSDR Beta but it's not as frequent as earlier releases. Closing out DAX and restarting clears the issue. 

Cal/N3CAL
(Edited)
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Dick B

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Thanks everyone for the tip on this known problem being caused by long duty cycles.  I don't normally leave the rig on when not in use but I did this time ... so that's obviously the cause.  If I see it again I'll just restart DAX and/or CAT to see if that's sufficient.  

As long as I'm aware of the issue and have a work-around I'm happy for now.  I have many such issues and work-arounds with HRD - just the nature of much software.  
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NM1W

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I can get the dax corruption in anywhere from a few minutes to few hours; I'm running smarsdr 1.9.13 with 4/wsjtx sessions. I also get CAT wrapped around itself fairly often too...  So restarting both, then clicking "retry" 4 times (once/wsjtx) gets it going again.. but its very annoying..
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Dick B

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Since this is supposedly a known problem, how can we know if/when Flex fixes it?  Is there a Defect#  associated with it, or is it known by a specific title we should watch for in the Release Notes?  
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Tim - W4TME, Customer Experience Manager

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There are several defects entered for this particular DAX behavior.  The primary one is #2391.