WSJT-X not decoding. I am seeing signals in the WSJT-X waterfall; clock seems accurate

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WSJT-X not decoding. I am seeing signals in the WSJT-X waterfall; I can send CQ and getting RF out; the clock seems to be within 0.2 secs of accurate. The incoming signal strength is between 40 and 6 dB. Could this be a software glitch induced by Windows 10? When I say it is not decoding I mean absolutely NOTHING is decoding, whether JT-65, JT-9, FT-8. I'm using a Flex 6700 with version 2 software.
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Gregory Stobbs

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Posted 10 months ago

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Bob Craig, K8RC

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Make sure you are using USB or DIGU.  

If you use LSB or DIGL it will cause the problem that you describe by inverting the phase of the recovered signal from normal.
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yes I have had the same thing happen. It is frustrating because everything looks like it should be working. Waterfall shows activity but nothing decodes. I uninstalled, reboot, reinstall and it decodes. I spent a lot time before doing that checking settings, making sure there was another program running that might causing a conflict, etc. So just saying it doesn't time must time to just flush it out and start it over. It could also be worth uninstalling the wsjt-x software at the same time and reinstall with a fresh download. The configuration will stay in place. Everyone has their own solution.
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Chris DL5NAM

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Reduce audio input level
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Bob Gerzoff, WK2Y

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One oddity I have noticed is that you have to tune\transmit momentarily before decoding occurs.
73, Bob WK2Y 
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Working here. Just got off 160 working several European stations. Sounds like it’s going to e a good night!
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Last evening I had signal on the waterfall but no decoding. stopped DAX and restarted it. Good decoding followed. What perplexes me is that FRS has known about DAX being iffy software, yet they have not done anything to fix it, nothing.
They're to involved trying to satisfy a certain few with their $7000.00 amplifier.
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NX6D Dave

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I would send the question to the WSJT-X developer's email reflector.  Their point of view will be oriented toward their program as long as it can be shown that the signal is reaching the program.  Our point of view is sorta the opposite.  We can advise about getting the signal into the program, but after that, we don't know any more than anyone else, except the WSJT-X experts.

Information about how to join that reflector can be found at
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I believe you have a clock anomaly. I had the same problem but it was due to clock synchronization.
I installed the Meinburg clock software that Ria suggested. Problem went away. GL
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Al K0VM, Elmer

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I have seem my WSJT stop decoding after a period of time.. Usually fixed by closing and restarting the DAX GUI, WSJT-X and/or the radio..  For me it is likely to stop decoding if the CPU is heavily loaded..  I do run Meinburg for clock sync.
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So after one of the recent Windows 10 updates I had to reinstall Meinberg. All back to normal.
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Rick Hadley - W0FG

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WSJT-X drops radio control of both my radios (6400 & 6500) every few hours.  With the current version of WSJT-X I'm running  (set up under Flex 6K control)rather than Kenwood) it requires a reboot of the computer to get it back.  I haven't seen an occurance of it just stopping decoding without losing connection to the rigs.  I run Dimension4 for sync.
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Ria - N2RJ, Elmer

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That is a bug in hamlib I think. I have seen that as well. I switched to TS2000. 
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Ria - N2RJ, Elmer

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There are a few things I have noticed that  will cause WSJT-X to stop decoding:

1. DAX stream is corrupted. Basically if you listen to the audio it is stuttering or distorted. This is a known issue I believe. Restart DAX app and it will come back. 

2. Your PC doesn't have enough horsepower to run DAX and whatever else you're running. I have seen one case where when the person started up Teamviewer that DAX started to stutter. Teamviewer is very expensive with CPU. DAX is very sensitive to CPU usage.

3. Bandwidth and default filter for DIGU. Somehow for some reason Flex decided that the default filter for DIGU should be set to 1kHz centered on the channel. This doesn't work well with nearly all digital modes and with WSJT-X you will miss decodes. Set your bandwidth to 3kHz. 

In cases 1 and 2 you will still see the signals on the waterfall. In case 3 you will see them in narrow bandwidth.

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Bob Gerzoff, WK2Y

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More a work around than a real solution, I have been running JTDX and it runs all day with no issues.   Seems to decode more signals per pass the WSJT-X. There is also a JTDX Alert to go with it.
73, Bob
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Your not running PSKreporter web site?  I have had a problem with PSKreporter website by some unknown reason stopping the WSJT decode. It happens almost immediately when I run that site. I found by turning off the grey line overlay the problem goes away.

Before you say it I have  a fast computer with lots of resources and when this problem is happening  I have low CPU and Mem use.

This seems to happen most when using Chrome browser.  Not saying this is your problem but thought I would bring it up.
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I am having the same problem with my new 6600, WSJT-X, JTAlertX with one instance of WSJT-X. The more programs that are running the worse it gets. After reading the above discussion I was decoding on 20m missing a 15 segment once in a while. When I closed chrome it stopped dead in its tracks. I monitor the CPU and see that the CPU jumps significantly when starting up Chrome or doing some things. WSJT-X does not like it when the CPU hits 100% even for a short time in the cycle. My computer is a Dell Laptop (old) I5 3210M 2 core 4 virtual CPUs with turbo boost. Often it just stops decoding and even closing and reopening WSJT-X doesn't restart, sometimes after restart is decodes a couple cycle and stops completely. 

I did stop and restart DAX and it came back to life even though the audio streamin and the WSJT-X waterfall continued to show normal audio. The audio levels on DAX and WSJT-X waterfall don't change. Looking at new computer but that won't help the DAX what ever is going on there. The decode is either all there or nothing.

Your post and replies from others has given me a good insight to what is happening. Great help.

73 Bill W9JJB
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I was trying to run wsjt with a "netbook". 1.6gzh atom chip with 2gig ram and it would not decode. Maybe got 10 decodes in an hour. Tried another and it did the same. Put on a real laptop i3 and 8g ram and it took right off.

Sam kf6vik

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Art, N4PT

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Sounds like a clock issue. I have tried a number of the clock setting programs and finally settled on BitTimeSync by IZ2BKT easy to use and works fine. Tried Meinberg but it seemed a bit complex and overkill. 
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Rick - W5FCX

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For me it was time sync issue. Just right click on the Windows clock and configure its Internet time to sync with NIST NTP time source and all is good!
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Rick - W5FCX

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Thanks Tim. That worked.
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Tim - W4TME, Customer Experience Manager

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Glad to be of assistance.

Now my second bit of NTP wisdom...

Use at least 4 NTP servers and use the pool servers in your region that randomly select stratum 1 and 2 public time servers.

I use:
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Joe - KB6IGK

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Same issue with 6600...Win 10. Noticed a Win10 update occurred yesterday. 

Updated Meinberg
Added a 4th NTP server per Tim's suggestion
Tried Ria's 3 tips
...still no decode.

Other suggestions?
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Joe - KB6IGK

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Okay. After trying various of the fixes posted above, including the Hamlib-modified version of WSJT-X by David Decoons (which worked perfectly for months),  the only solution that works now is selecting "TS-460" in the radio config. Problem resolved.
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thanks!   if the green division lines in the waterfall do not lie between the message bursts... you're going to have a bad time. :)