CubicSDR VS Gqrx

GQRX works pretty well for me. There is also CubicSDR and SDRAngel afaik - you might just want to play around with them and see which you are most comfortable with. Source: 10 months ago

If you don't need the web interface and your usual desktop SDR software supports rtl-sdr tcp mode, you can easily set up a small board that calls rtl-sdr with the appropriate parameters so that it will wait for a remote connection from the above software, not unlike what happens with WebSDR, but you would be using your usual desktop SDR application which would be native and much more snappy than a web browser. ... - Source: Hacker News / 6 months ago

GQRX works pretty well for me. There is also CubicSDR and SDRAngel afaik - you might just want to play around with them and see which you are most comfortable with. Source: 10 months ago

For most signals (including analog AM and FM modes) you can use a laptop with an RTL-SDR USB dongle (fairly cheap), or another SDR, and a reasonably tuned antenna. Various RTL-SDR models can tune from around 500 kHz up to 1.75 GHz with 3 mhz of bandwdith, and works with free software like SDR# for Windows and GQRX for Linux. It works with lots of other software, too, for ham modes, digital modes, etc. Source: over 1 year ago

Some of the Crossfire modules have a rudimentary spectrum analyzer function on them that might help you identify if there are other devices operating in the 900MHz band around that area, but I'm not sure the nano TX is one of them. I have a couple RTL-SDR dongles or equivalent I'd use with GQRX as a cheap spectrum analyzer if possible. Source: over 1 year ago

Yes, a dongle from https://www.rtl-sdr.com/ Then I use gqrx to record the signal. https://gqrx.dk/ and SOX to downsample it https://sox.sourceforge.net/ Then pass it through wxtoimg to get the picture https://www.wraase.de/wxtoimg/. Source: over 1 year ago