Question

1) What instrument makes a square wave on a time-domain graph? What harmonics are involved in making that graph?

2) What instrument makes a saw-tooth wave on a time-domain graph? What harmonics are involved in making that graph?

Answer 1

Square waves are universally encountered in digital switching circuits and are generated by logic devices. They are used as timing references or "clock signals" because of them being like a pulse .

The ideal square wave contains only components of odd-integer harmonic frequencies (of the form 2π(2k − 1)f).

Oscilloscopes produces  use a sawtooth wave and sawtooth and waves are among the most common waveforms used to create sounds .

Sawtooth waves and real-world signals contain all integer harmonics.

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