Attenuation settings and usage
To protect the tinySA from damage from strong signals or to check the possible overloading of the tinySA it is recommended to always ensure you have the correct attenuation. Internally the display data is corrected for the applied attenuation. This is the display with an attenuation of -3dB.
The fundamental is at 30.3MHz with a strength of -35dBm.
When increasing the attenuation the signal and all its harmonics stays at the same level but the noise floor moves up.
If, as in above image, the harmonics stay at the same level when increasing the attenuation, you can be sure these are not internally generated but present in the input signal. When the harmonics decrease in strength when increasing the attenuation you have been overloading the tinySA and the harmonics are (partially) internally generated.