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locked Distorted audio on receive


Bill Howard
 

i have been using JTAlert with WSJT latest versions with my IC-7300 and i3 PC successfully.  Lately I notice on the WSJT waterfall, the signals become distorted and will not decode with JTAlert running, as in picture below.  When I turn JTAlert off, signals return to normal and decoding begins again. See second picture. Tried an older version of JTAlert with same result. I suspect the problem may be related to a software issue, but I'm not sure where. Any thoughts?


Brad Penn
 

Hi Bill,

Not sure how JT Alert would cause this, but I have seen the same thing when I have forgotten to turn off "NR" noise reduction on my IC-7300.

Hope this helps,

Brad
KD5ZAT


Bill Howard
 

I'll check that, I had been switching back and forth between SSB with NR, and FT8.


Bill Howard
 

No joy. Tried resetting the JTAlert audio output,  and that seemed to help.


HamApps Support (VK3AMA)
 

On 29/08/2020 3:40 pm, Bill Howard wrote:
No joy. Tried resetting the JTAlert audio output,  and that seemed to help.

What is the spec of your PC, What version of Windows, how many CPU cores, how much installed memory? Are you running other applications like a multitab web browser?

JTAlert is very unlikely to be directly affecting the WSJT-X received audio. When WSJT-X is in RX mode, when your observing a distorted waveform in the Waterfall window, JTAlert is sitting there "twiddling its thumbs", sitting idle waiting for WSJT-X to process the audio and produce decodes ate the end of the Rx period. It is only after decodes have been produced that JTAlert CPU usage will increase, the same as WSJT-X at the end of the Rx period.

During Rx, before decodes processing, WSJT-X and JTAlert are both effectively idle, this can be observed in TaskManager.

JTAlert audio is only played after processing decodes and generating Alerts and that wont affect what is happening during WSJT-X receive. The simplest way to test is mute the JTAlert audio via the "Sound" menu. When set to "Sound OFF" there is zero audio coming from JTAlert.

If shutting down JTAlert improves the visual appearance of your waterfall, that suggests that your PC is very likely heavily loaded and the freeing up of cpu/memory resources by stopping JTAlert was the real fix. You will likely see similar results if you shutdown other applications like browsers, email client, skype, etc.

de Laurie VK3AMA


Bill Howard
 

Thank you Laurie. Very much appreciate your software. I am running a refurbished Dell Optiplex 3010 on Win 10 latest version, with 4gb memory. Only running WSJT-X and JTA lert. Tried everything you suggested with no joy. Switched to an earlier version on WSJT-X and the problem is gone!  Live and learn.
73 - Bill WB3V


HamApps Support (VK3AMA)
 

On 31/08/2020 4:42 am, Bill Howard wrote:
Thank you Laurie. Very much appreciate your software. I am running a refurbished Dell Optiplex 3010 on Win 10 latest version, with 4gb memory. Only running WSJT-X and JTA lert. Tried everything you suggested with no joy. Switched to an earlier version on WSJT-X and the problem is gone!  Live and learn.
73 - Bill WB3V

Bill, What version of WSJT-X did you downgrade to?

How many CPU cores does the "Dell Optiplex 3010" have?  What model is the cpu (i5 ????).

de Laurie VK3AMA


Bill Howard
 

On Mon, Aug 31, 2020 at 04:22 AM, HamApps Support (VK3AMA) wrote:
On 31/08/2020 4:42 am, Bill Howard wrote:
Thank you Laurie. Very much appreciate your software. I am running a refurbished Dell Optiplex 3010 on Win 10 latest version, with 4gb memory. Only running WSJT-X and JTA lert. Tried everything you suggested with no joy. Switched to an earlier version on WSJT-X and the problem is gone!  Live and learn.
73 - Bill WB3V

Bill, What version of WSJT-X did you downgrade to?

How many CPU cores does the "Dell Optiplex 3010" have?  What model is the cpu (i5 ????).

de Laurie VK3AMA


 The Pc Uses an 3.3 GHz Intel core i3-3220.
]dual core on the Ivy bridge architecture. Due to hylerthreading, the two cores can handle up to four threads in parallel. Each core has a base speed of 3.3 GHz.

I downgraded to an early 2.15 version of WSJT-X and the system together with JTAlert is back to working well.