Awful scratchy sound monitoring CW side-tone

JJ4SDR
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Location: TEXAS, USA

Awful scratchy sound monitoring CW side-tone

Postby JJ4SDR » Sun Nov 28, 2021 7:23 pm

Been working a contest this week-end, to put the ANAN 7000 DLE MKII (Thetis v.2.8.11) through its paces on CW. I am monitoring and/or listening to the CW side-tone with head-phones plugged into the front audio port on the ANAN. At first I thought the problem might have been caused by the head-phones (it is a quality pair) but all 3 pairs of headphones exhibit the same problem so I would think this has nothing to do with headphones.

Every now and then the audio from the front-port connector gets extremely “scratchy,” similar to the noise that a potentiometer in need of cleaning makes! :roll: The sound stays on and while I am listening/monitoring the band it gets so bad that it is very difficult to hear actual stations! I can get rid of the racket if I switch off Thetis by clicking on the soft icon at top left-hand corner and switching it back on. That done, the radio works well with the awful “scratchy” sound gone only to appear again at some point.

Any thoughts on the cause for the above?

Other ways to monitor the side-tone when on CW that hopefully won’t suffer from the same phenomenon described above?

Best!
JJ
PC: 8 Core i7-10700 CPU @ 2.90GHz, NVMe SK Hynix 512 GB SSD, 32GB RAM
Windows 10 Home, Version 22H2
Thetis v2.10.4.3 x64
Protocol 2 v2.1.18
JJ4SDR
Posts: 436
Joined: Fri Jul 30, 2021 10:09 pm
Location: TEXAS, USA

Re: Awful scratchy sound monitoring CW side-tone

Postby JJ4SDR » Tue Nov 30, 2021 9:29 pm

On another note, I think this issue has nothing to do with using CW but there clearly is something going on with the audio that is available through the front audio port (headphones port).

I know there are many audio ports on the back of the ANAN so perhaps I used one of them when I am on CW. I can't hear the side-tone as I am using VAC for RX/TX audio generally speaking.

Any suggestions will be gratefully received!

Best!
JJ
PC: 8 Core i7-10700 CPU @ 2.90GHz, NVMe SK Hynix 512 GB SSD, 32GB RAM
Windows 10 Home, Version 22H2
Thetis v2.10.4.3 x64
Protocol 2 v2.1.18
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w-u-2-o
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Joined: Fri Mar 10, 2017 1:47 pm

Re: Awful scratchy sound monitoring CW side-tone

Postby w-u-2-o » Tue Nov 30, 2021 10:42 pm

All audio that flows through the hardware unit goes via the CODEC chip. Refer to this topic: viewtopic.php?f=12&t=2612

Thus if it was a hardware problem it is unlikely that changing to rear panel connections would help.

Also, since the problem goes away when Thetis is reinitialized, this implies that there is some sort of buffer that is ultimately overflowing/over-running. This is very odd, AFAIK you are the first and only person to experience this problem.

It might not have anything to do with audio buffering. A sure way to test that would be to use VAC as an experiment. If the problem is still experienced with VAC then you might consider increasing the IF processing buffer sizes in Setup > DSP > Options (buffer sizes, not filter sizes).

What sort of CPU load are you seeing when using the radio?
JJ4SDR
Posts: 436
Joined: Fri Jul 30, 2021 10:09 pm
Location: TEXAS, USA

Re: Awful scratchy sound monitoring CW side-tone

Postby JJ4SDR » Wed Dec 01, 2021 1:12 am

Hi Scott,

Thank you for your consistent support and advice. :)

VAC: I have never had the issue I am describing. However, I can’t hear the side-tone of CW when using VAC. Should I click of the soft icon that says “DUP?” The latency of hearing the side-tone (using VAC it is possible) would likely not work either when I am sending at north of 35 WPM speed as the side-tone would be a dot or two behind actual key closure.

The PC is dedicated to ANAN and the CPU load usually hovers at around 5% so the PC wouldn’t be the culprit. I will see if the “Buffer size” might remedy the glitch.

Best!
JJ
PC: 8 Core i7-10700 CPU @ 2.90GHz, NVMe SK Hynix 512 GB SSD, 32GB RAM
Windows 10 Home, Version 22H2
Thetis v2.10.4.3 x64
Protocol 2 v2.1.18
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w-u-2-o
Posts: 5539
Joined: Fri Mar 10, 2017 1:47 pm

Re: Awful scratchy sound monitoring CW side-tone

Postby w-u-2-o » Wed Dec 01, 2021 1:10 pm

Yes, no sidetone via VAC, a sad design limitation that ought to be fixed :(

You should always have DUP turned on. Short hand for "full duplex", DUP mode uses RX1 during transmit to show you your actual transmitted signal, picked off at either the internal RF sampling coupler or the external one if you are so equipped. It will not fix the VAC sidetone problem, though.

Since it's not happening with VAC that seems to rule out PC software related effects.

Grasping at straws: are you running Protocol 2 firmware? If so, you might temporarily switch back to Protocol 1 and see if the problem persists. This would help identify whether or not P2 firmware is having any timing closure problems on your hardware.
JJ4SDR
Posts: 436
Joined: Fri Jul 30, 2021 10:09 pm
Location: TEXAS, USA

Re: Awful scratchy sound monitoring CW side-tone

Postby JJ4SDR » Thu Dec 02, 2021 3:05 pm

Scott,
Thanks for the comments and yes, I concur, side-tone availability through VAC would make this radio even better :)
And, yes, I do know what "DUP is shorthand for, but normally I don't keep it switched on.
Using Protocol 1.
JJ
PC: 8 Core i7-10700 CPU @ 2.90GHz, NVMe SK Hynix 512 GB SSD, 32GB RAM
Windows 10 Home, Version 22H2
Thetis v2.10.4.3 x64
Protocol 2 v2.1.18
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w-u-2-o
Posts: 5539
Joined: Fri Mar 10, 2017 1:47 pm

Re: Awful scratchy sound monitoring CW side-tone

Postby w-u-2-o » Thu Dec 02, 2021 3:41 pm

If you upgrade to Protocol 2 you can then use the full QSK feature first introduced in Thetis 2.6.4 (and only supported in P2 on Orion and Orion MK II based models). This will provide sidetone via VAC, implemented by receiving a full duplex version of your transmitted signal.

See here for the 2.6.4 release notes discussion of the QSK feature: viewtopic.php?f=9&t=3049&p=7168

Or you could take an old school/brute force approach to solving the VAC problem by putting an old school tone generator across your paddle/key output.
JJ4SDR
Posts: 436
Joined: Fri Jul 30, 2021 10:09 pm
Location: TEXAS, USA

Re: Awful scratchy sound monitoring CW side-tone

Postby JJ4SDR » Thu Dec 02, 2021 9:56 pm

Thanks Scott!

Will consider upgrading to Protocol 2.

Best!
JJ
PC: 8 Core i7-10700 CPU @ 2.90GHz, NVMe SK Hynix 512 GB SSD, 32GB RAM
Windows 10 Home, Version 22H2
Thetis v2.10.4.3 x64
Protocol 2 v2.1.18

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