"Echo" with dual receive, Prot 2, thetis 2.9.0.6x64

N4XD
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"Echo" with dual receive, Prot 2, thetis 2.9.0.6x64

Postby N4XD » Sun Jan 29, 2023 5:52 pm

Set up

Protocol 2. Thetis 2.9.0.6 x 64
7000dle with both receivers on. Synch'd together
Computer: 11th gen I7, 64Gb ram

During the CQ160 contest (and have happened with other CW contests), after some period of time operating with both receivers synch'd together, they sound like they have lost synch. In the headphones, sounds like aurora echo/ flutter. I found, through trial and error, that briefly turning RX2 off then back on, "fixes" the issue but it comes back.

I am not using an external 10 Mhz clock.

I don't recall this ever happening with earlier versions of Thetis but then my first contests with it there was, obviously, a lot of learning going on.

As you might suspect, this issue is not welcome in a contest. Makes it difficult to copy stations. and taking time out, even briefly, to reset the receiver or, even worse, reboot everything, is not ideal.

The computer is certainly powerful enough to handle the load. I turn off all other programs other than N1MM+ for logging. I used to have a web page open to monitor the RBN network but have found it leads to audio glitches. I can't understand this either as CPU usage is in the low teens and maybe 15% of RAM.

Any ideas, suggestions are, of course, welcome. I certainly hope this is an issue here which should be easy to fix.

Thanks

Ron
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w-u-2-o
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Re: "Echo" with dual receive, Prot 2, thetis 2.9.0.6x64

Postby w-u-2-o » Sun Jan 29, 2023 6:11 pm

The audio glitches with browser activity are due to the radio and browser sharing the same network interface. Add a dedicated NIC for the radio.

As for the dual receive getting out of sync, this is probably due to a growth in the RX2 audio buffer length after some time. Are you by chance using VAC?
N4XD
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Re: "Echo" with dual receive, Prot 2, thetis 2.9.0.6x64

Postby N4XD » Sun Jan 29, 2023 6:47 pm

Will try the separate interface.

No, VAC is off.

Ron
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Re: "Echo" with dual receive, Prot 2, thetis 2.9.0.6x64

Postby w-u-2-o » Sun Jan 29, 2023 6:57 pm

If VAC is off then I'm afraid I've got no good suggestions for you regarding the audio sync issue.

In Setup > DSP > Options you might try increasing the buffer sizes (not the filter sizes).

Using an external 10MHz clock will have no bearing on this problem.
N4XD
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Re: "Echo" with dual receive, Prot 2, thetis 2.9.0.6x64

Postby N4XD » Sun Jan 29, 2023 7:14 pm

Scott thanks. I always run with binaural on. With both receivers on I have been running it with both. I'm going to experiment and turn it off. With both receivers on I think there is no (little?) benefit.

Will let it run like this for a while and see if the issue is resolved.

Added 2nd nic card dedicated to the radio. Thanks for that. Looking forward to glitch free audio now :)

As always, thanks!

Ron
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Re: "Echo" with dual receive, Prot 2, thetis 2.9.0.6x64

Postby w-u-2-o » Sun Jan 29, 2023 7:18 pm

Ron,

Don't forget to disable all unnecessary protocols on the dedicated card. See my post here: viewtopic.php?f=22&t=4127&p=19209#p19209

73,

Scott
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Re: "Echo" with dual receive, Prot 2, thetis 2.9.0.6x64

Postby N4XD » Sun Jan 29, 2023 11:20 pm

In testing for the last hour of the CQ160 contest adding the dedicated nic for the radio solved the audio issues. turning off binaural (bin) fixed the echo issue.

Scott, as always, thanks for your help.

Ron
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Re: "Echo" with dual receive, Prot 2, thetis 2.9.0.6x64

Postby w-u-2-o » Sun Jan 29, 2023 11:26 pm

:)

I've never found "binaural" very compelling, but some people really like it.
N4XD
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Re: "Echo" with dual receive, Prot 2, thetis 2.9.0.6x64

Postby N4XD » Sun Jan 29, 2023 11:29 pm

Scott I've found that, for a very weak station, it can help me, sometimes, pick them out. And, for single receive, it does do some separating of stations ear to ear which also helps pull them out. I had been running it all the time. Will still do that unless RX2 is on.

Would be interesting to find out what the issue is that's causing what I experienced.

R
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Re: "Echo" with dual receive, Prot 2, thetis 2.9.0.6x64

Postby N4XD » Sun Feb 05, 2023 2:20 pm

Scott getting back to the dedicated NIC for the radio, I read the information you posted a number of years back on turning off stuff that isn't needed.

For the card setup, under advanced, what does need to be turned on for the interface to work with the radio? And you said, in that same post, some small tweaks would help even more. Such as?

Right now, with the dedicated card, most audio glitches are gone. Except for when I run diversity on the Anan. Seems if I turn it on and off a number of times during testing, something happens and some serious audio issues (more than simple momentary glitches) occur. After a couple seconds these mostly die away.

Always something......

Thanks

Ron
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Re: "Echo" with dual receive, Prot 2, thetis 2.9.0.6x64

Postby w-u-2-o » Sun Feb 05, 2023 2:45 pm

Ron,

The post you refer to is right here: https://community.apache-labs.com/viewtopic.php?f=22&t=4127#p19209

You literally only need TCP/IPv4 turned on, that's it. Turn on Npcap (or Winpcap) if you want to use Bootloader.

As for messing with the advanced settings, on most cards you'll find very little difference with any of these settings, but sometimes you get lucky. I like to use iPerf to measure any changes, primarily in UDP performance. I had one card that wanted flow control off. The old card died and now I have a new card that wants flow control turned on. So YMMV quite a bit, and it's rare that anyone can tell you definitively what the exact best settings are. Tthe stock settings do tend to work pretty well. If you do start to go down the iPerf rabbit hole and want to post about it please start a new topic in the network sub-forum.

Finally, don't be so quick to blame literally every problem on poor networking performance. There are latent bugs and instabilities in both the firmware and software.

73,

Scott
N4XD
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Re: "Echo" with dual receive, Prot 2, thetis 2.9.0.6x64

Postby N4XD » Sun Feb 05, 2023 2:50 pm

Scott as always, thanks.

I wasn't meaning to "blame" this on networking.....or anything. Rather I was/ am trying to understand this stuff better :)

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