Sine

[ElectronicsDevil]

Why do we use sine wave for most of the testing operations?
What are advantages of using it?
What other signal we can use and is best if sine wave is not available?

 

[audioguru]

A pure sine-wave is a single frequency. Any other waveshape has harmonics which are additional frequencies.

 

[Sceadwian]

So if you send in one frequency and you get out other frequencies you can measure the linearity of the circuit at that frequency.