FFTViewer apparently not working

Hi everyone,
I am pretty new to the SDR world. I have a LimeSDR mini and LimeSuite installed.
One of the first things suggested in the tutorial is to use the FFTViewer to analyse the RF spectrum.

In order to create some visible pattern I placed an Arduino with a 433MHz transmitter sending a repeated message every second.
After opening LimeSuiteGUI and connecting the LimeSDR mini, I click RESET and DEFAULT to make sure I am starting from a working condition, then open the FFTViewer and set the Nyquist frequency to 443 and press START.
The resulting spectrum seems flat, without any trace of the close by transmissions.

To see if it was a connection problem, I tried touching the antenna and noticed a sudden change in the spectrum.

Why can’t I see the 433MHz transmission? Is the LimeSDR actually “seeing” the RF transmissions or just outputting random noise?

The Nyqvist frequency setting is related to the amount of bandwidth collected by the SDR. The Nyqvist frequency is not related to the center frequency.

LimeSDR mini can sample at most 30.72 MHz bandwidth. An normal Nyqvist setting in the fft viewer is 5 (MHz).

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