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Low quality reception (?) with sdrangel vs gqrx #github

cartellicartelli
 

Hello everyone, here's a newbie question.
Running SDRAngel on Linux, git commit acd08925368ba1ee2f35469314abdc4dea02a1fe (v 4.12.1).
Hardware is RTL-SDR.

I was trying to tune to FM broadcast radio and demodulate it.
The spectrum though looks quite "bad" - the peaks aren't much as expected and they are low. 
Here's a pic when showing the "max hold" (red line) : https://ibb.co/kD8g0sd

I fiddled with the antenna to no avail.

Then I tried gqrx and surprisingly the signal looked much neather: several clean spikes as one would expect on the FM broadcast range 88-108. 
Here's a pic: 
https://ibb.co/8Dxsrkg

So I guess it's a matter of configuration. 
What could have I done wrong?
Here's the settings.
https://ibb.co/BTmrbTB

Thank you very much for any help!

cartellicartelli
 

I found the answer ten minutes later. Sorry for having bothered you. 
I post it in case it could be useful to other newcomers:

It was the gain. I needed to turn it up:

It seems like the gqrx defaults were more suited to this FM broadcast listening task maybe.
Afterwards I got a clean FFT:


Thanks :-)

Brian Whelan
 

Low gain setting????


On Fri, 22 Nov 2019, 11:34 cartellicartelli, <spelta@...> wrote:
Hello everyone, here's a newbie question.
Running SDRAngel on Linux, git commit acd08925368ba1ee2f35469314abdc4dea02a1fe (v 4.12.1).
Hardware is RTL-SDR.

I was trying to tune to FM broadcast radio and demodulate it.
The spectrum though looks quite "bad" - the peaks aren't much as expected and they are low. 
Here's a pic when showing the "max hold" (red line) : https://ibb.co/kD8g0sd

I fiddled with the antenna to no avail.

Then I tried gqrx and surprisingly the signal looked much neather: several clean spikes as one would expect on the FM broadcast range 88-108. 
Here's a pic: 
https://ibb.co/8Dxsrkg

So I guess it's a matter of configuration. 
What could have I done wrong?
Here's the settings.
https://ibb.co/BTmrbTB

Thank you very much for any help!