QRN or Something Else

SteveKH6CT
Posts: 9
Joined: Thu Aug 20, 2020 12:55 pm

QRN or Something Else

#1

Unread post by SteveKH6CT »

Greetings...
Experiencing a minor issue with the waterfall. Display changes in a way I cannot explain or resolve. Please see the video; the issue appears at the beginning and end of the 2+ minute recording. Disruptions appear and last in random periods and durations. Is this perhaps forces of nature, or have I made an incorrect setting somewhere ?

Thanks, Steve KH6CT
Attachments
SDR Console 2021-02-24 13h 02m 35s.mp4
(18 MiB) Downloaded 67 times

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Simon G4ELI
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Joined: Thu Aug 06, 2020 7:27 am
Location: Mawnan Smith
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Re: QRN or Something Else

#2

Unread post by Simon G4ELI »

Looks like AGC. Open the Ribbon Bar, Home so I can see the settings.
Simon Brown :shock:
www.sdr-radio.com

Do not send me direct e-mail, thank-you!

SteveKH6CT
Posts: 9
Joined: Thu Aug 20, 2020 12:55 pm

Re: QRN or Something Else

#3

Unread post by SteveKH6CT »

Ribbon bar, Home
Attachments
Screenshot-2021-02-24-145543.jpeg

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KA1GJU
Posts: 264
Joined: Tue Aug 11, 2020 2:16 pm

Re: QRN or Something Else

#4

Unread post by KA1GJU »

Looks like the SDRC is way out of date, even the version isn't published on the home screen along the top ribbon.
Big difference in behavior when going from RF gain of 5 to RF gain of 6, the gain actually decreases as seen by the screen getting darker in attached image. So I run mine at 6 to 7 depending upon what band I am RXing.

I found if the IF is in Auto, the AGC will pump if there is a strong pulsing signal in the operating bandwidth. Similar to what you see with the perfectly flat bands of light and dark across the waterfall. Think of a lone, strong CW signal antagonizing the AGC, so I run -30 to -35 Manual and it goes away! Your current version of the software doesn't even have the option, I don't think, or it's just not published in your version. Hence you need to upgrade SDRC to the latest download!

Mine is on an EFW of +150 feet, so it hears very well and will overload at a moments notice, so try my settings for starters, then adjust from there.
This is the last if the SDRPlays I have (lightning hit) and because of the one and only one I have, the server which it is connected to has to have an AM BC filter to tame the overload and images seen from 160M to 75M. The Airspy Discovery is a much better unit, IMHO. But I still have users that use that POS, so it's still online... for now.

Oh, open the DSP window so we can see your settings there too! (see my attachment)

73 de Kriss KA1GJU
Home of the Super Station SDR Servers in NH, USA
Attachments
RSP1Asettings.png
73 Kriss KA1GJU Home of the KA1GJU Super Station SDRC Servers in NH, USA (FN42mw & FN43na)

SteveKH6CT
Posts: 9
Joined: Thu Aug 20, 2020 12:55 pm

Re: QRN or Something Else

#5

Unread post by SteveKH6CT »

Thanks Simon and Kriss...

Does appear to be an AGC issue. In the ribbon bar, AGC was ON; switched it OFF and the black/dark bars disappeared. In the DSP panel, AGC is Medium. All seems to be running well now.

Just a comment... From looking at my previous screengrab attachments, Kriss thought my software might have been out of date. When a screengrab using the onboard feature is made, the very top tool bar is all black to the right of "Select previous frequency" icon. So, parties to the request for help may not know what version is operating. Using a third party screen grab shows the SDRC version. See the attached files.

Thanks again for the help!!

73, Steve KH6CT
Attachments
Main+DSP1 3rd Party SS.jpg
Main Onboard SS.jpeg

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KA1GJU
Posts: 264
Joined: Tue Aug 11, 2020 2:16 pm

Re: QRN or Something Else

#6

Unread post by KA1GJU »

Yes, I was gonna correct my post about that. Maybe Simon can fix that in the next edition. Since we are always using screen shots to help users with issues. It would be nice if the current user version is posted in the 'Screen Shot' button versus the Keyboard Prt Scrn... I actually use both. Especially when running two 'stances' of SDRC at the same time for antenna or SDR rig comparisons.

73 de Kriss KA1GJU
73 Kriss KA1GJU Home of the KA1GJU Super Station SDRC Servers in NH, USA (FN42mw & FN43na)

jdow
Posts: 800
Joined: Mon Aug 10, 2020 8:17 pm

Re: QRN or Something Else

#7

Unread post by jdow »

The screen shot SHOULD capture the title bar. I wonder what MS screwed up so that Simon's tool malfunctions. (But, then, I reflexively use alt-prtscrn and paint.)

{^_^}

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KA1GJU
Posts: 264
Joined: Tue Aug 11, 2020 2:16 pm

Re: QRN or Something Else

#8

Unread post by KA1GJU »

What baffles me is why does he have AGC available under the Radio Settings and I don't when operating an SDRPlay RSPA1A. Both of us are on 3.0.26
Although I am running mine via a server, not directly.

Simon? Did you change something in the 3.0.26 releases?

73 Kriss KA1GJU
Attachments
ver3026.png
73 Kriss KA1GJU Home of the KA1GJU Super Station SDRC Servers in NH, USA (FN42mw & FN43na)

SteveKH6CT
Posts: 9
Joined: Thu Aug 20, 2020 12:55 pm

Re: QRN or Something Else

#9

Unread post by SteveKH6CT »

I noticed that too, Kriss. What I really don't understand is why I have an AGC selection on the ribbon bar (set to OFF) and also an AGC selection in the DSP panel (set to ON). But then, I grew up with "glass valves", so that may lead to my not understanding.

73, Steve KH6CT

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KA1GJU
Posts: 264
Joined: Tue Aug 11, 2020 2:16 pm

Re: QRN or Something Else

#10

Unread post by KA1GJU »

What build is your v3.0.26?
Click on Help, About...

73 Kriss KA1GJU
Attachments
Ver3.27.png
73 Kriss KA1GJU Home of the KA1GJU Super Station SDRC Servers in NH, USA (FN42mw & FN43na)

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