I am new at this. I would like to transmit an audio signal cleanly using WBFM but I see two signal peaks occur around my fundamental frequency when I start transmitting.

In this case I am using a 1Khz tone but also when I send a song, at high frequencies the song is distorted due to the two signal peaks that appear.

How can I fix this?

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    $\begingroup$ What is the problem exactly? It looks pretty good, apart from maybe more 3rd harmonic than expected in the decoded audio $\endgroup$ – hobbs - KC2G Aug 9 '18 at 2:53
  • $\begingroup$ What would be the reason that these harmonics are being produced and how could I avoid them? I do not know if it's a software or hardware problem. I would like to be able to transmit in a clean way. $\endgroup$ – Lalo Mendez Aug 9 '18 at 3:40
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    $\begingroup$ hint: the operating system you're running on the pi has a screenshot functionality, and so does the GNU Radio companion; don't use your camera to take a picture of your screen, but use your network to copy the screenshot file from your Pi to your computer. $\endgroup$ – Marcus Müller Aug 9 '18 at 9:34
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    $\begingroup$ Also: don't use the WX gui widgets. We're in the process of removing them from GNU Radio, since we can't support them anymore, they don't work on many platforms, and use far more CPU to do the same job as their Qt siblings. $\endgroup$ – Marcus Müller Aug 9 '18 at 9:35
  • $\begingroup$ Harmonics can happen by any non-linearity. You might be overdriving your RTL dongle with too much input power. You might be overdriving your Lime. There might be completely other things wrong. $\endgroup$ – Marcus Müller Aug 9 '18 at 9:36

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