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PostPosted: Fri Feb 05, 2016 2:42 pm 
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You can use GQRX to test it it has Polar Modulation Stereo build in (I've tried it and it works but there is some hiss)

GQRX for windows: https://github.com/pothosware/PothosSDR/wiki/GQRX


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PostPosted: Sun Feb 07, 2016 5:04 pm 

Joined: Mon Mar 17, 2014 6:42 pm
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Hi,

basically it works, the Stereo LED is coming up. Sound is also stereo but the bass-area is over-accentuated which might be due to the 14db amplification in the tuner of the reduced carrier signal. I think when the attenuation is implemented, it will be fine. So far: great first step


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PostPosted: Mon Feb 08, 2016 12:02 am 
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Great! Thanks :)


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PostPosted: Mon Feb 08, 2016 6:22 pm 
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Getting closer:
https://www.wolframalpha.com/input/?i=( ... 6.4*f+*+i)

Multiplying the Fourier transform of the L-R signal with this might work.

Edit: Ok, that appears to work. Bad news though: Peak control is suddenly a lot worse. That might be acceptable for now. I'll run a build tonight for a new test, stereo should be ok for all freqs now.


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PostPosted: Tue Feb 09, 2016 1:31 am 
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viewtopic.php?f=14&t=7262&p=33318#p33318

Let me know if this one has correct stereo separation for the bass as well.
Note: DO NOT use Composite Clipping, it won't work with Polar Stereo. (I still need to add switching it off automatically when you select Polar).


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PostPosted: Thu Feb 11, 2016 8:55 am 

Joined: Mon Mar 17, 2014 6:42 pm
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Thanks Hans,

as being in Doha for the moment, I can test this on Friday 19th earliest.. Sorry :(

Christian


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PostPosted: Tue Mar 01, 2016 11:14 am 
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Any more info on this?


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PostPosted: Wed Apr 20, 2016 11:38 pm 

Joined: Wed Apr 20, 2016 10:58 pm
Posts: 4
The Polar Modulation in Stereo Tool works fine with a modified RFT Tuner ST3000 and a Home made
Polar Stereo Decoder with OPA `741, connected on MPX-Output, schematic from http://www.votshema.ru/621-shema-prosto ... v-chm.html (Pic 2)

The "Pilot" Volume must set on Maximum Value =18% to realise a 14dB reduced 31,25 kHz Subcarrier on FM Output.


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PostPosted: Wed Jun 08, 2016 8:33 pm 
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I am totally new to this forum, I made an account after reading this thread.
This weekend I will do some tests to see if my lower FM band tuner successfully can decode the signal.

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PostPosted: Fri Jun 10, 2016 10:24 pm 
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As promised did I do some test with this polar function.
First I decoded some audio with the normal CCIR stereo. My Polish tuner seemed to work rather well with this regular stereo.
After this I changed to polar stereo and unfortunately I discovered that my tuner doesn't support polar stereo.
I did also make a video of the spectrum with sdrsharp.
https://youtu.be/IC35nR6Xh8w

So for me does the polar seem to work rather good although I don't have the possibility to decode the Polar stereo.
So it would be really great if there was somebody that could write a polar plugin for Sdrsharp.

This video I made last year with a sporadic E skip. As you can see there are many stations on-air with stereo. Those stations all have to be in CCIR 19 KHz stereo.
https://youtu.be/ByTGEtckfM4
https://youtu.be/YTI6KWyHT2w (many stations are in mono or Polar)

If I will somehow find a possibility to decode the polar stereo I will post it here.

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