Distinguish harmonic sounds from non-harmonic

A standard difference between harmonic and non-harmonic sounds is that harmonic sounds tend to be periodic (in the time domain) in nature whereas non-harmonic sounds don't show any periodic properties since they're completely random.

1. What is non harmonic signal?
2. What is a first harmonic?
3. Which harmonic is the fundamental frequency?

What is non harmonic signal?

Non-Harmonic Spurious Responses are unwanted signals that are not related to the fundamental output frequency of the DUT. They are produced by the internal frequency synthesis of the DUT.

What is a first harmonic?

The fundamental tone is referred to as the first harmonic. This is generally louder than the other harmonics. A tone played at twice the frequency of the first harmonic is called the second harmonic. A tone played at four times the frequency of the first harmonic is called the fourth harmonic, and so on.

Which harmonic is the fundamental frequency?

The fundamental frequency or original wave is known as the first, or 1^st,, harmonic. The following harmonics are called higher harmonics.