In GNURadio Companion, I have created a very simple flow where I generate 1kHz, 2.0 Volts peak to peak sine, and feed it into an FFT sink, and a Time domain sink.

The reference dB in the FFT sink is set to 0, and the reference scale is set to 2.0.

As such, I would expect to see 0dB on the FFT display... But I instead see -10dB.

Why is this? Is it a problem in my understanding, or problem in GNURadio?

Thanks.!

https://i.sstatic.net/edPbx.png https://i.sstatic.net/N52Xd.png

In GNU Radio Companion, I have created a very simple flow graph where I generate a 1 kHz, 2.0 volts peak-to-peak sine wave, and feed it into an FFT sink and a time domain sink.

The reference dB in the FFT sink is set to 0, and the reference scale is set to 2.0.

As such, I would expect to see 0 dB on the FFT display, but I instead see −10 dB.

Why is this? Is it a problem in my understanding, or a problem in GNURadio?