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# gqrx

### Overview

* multi-platform, open source SDR application
* install on linux

```
sudo apt install gqrx
```

* Shows waterfall display as well as FFT display. Easier to detect signal transmission
* Easy to record samples to disk

### FM Radio

* launch with

```
gqrx --edit
# select the correct device
```

<figure><img src="/files/5Mwrt0WNXi3VHhv74pLh" alt=""><figcaption></figcaption></figure>

* in my case im using a RTL device so i select that one
* ensure you tune to the right frequency (remember its in kHZ not MHZ)
* select WFM (stereo)
* Can see the red in the waterfall display meaning there is a strong signal present

<figure><img src="/files/MNaWJmzkcTHA2QswN491" alt=""><figcaption></figcaption></figure>

* can bookmark frequency for easy return finding in the future

### Bands around FM

* you might notice two bands around strong radio signals as seen below

<figure><img src="/files/kiVHD4sQBMQjGsRFtYd7" alt=""><figcaption></figcaption></figure>

* i believe this is to define the stations, however i am unsure. seems to make sense