# Re: Does not have any harmonics

• posted

Hi,

> Why does a sinusoidal waveform alone does not have any harmonics or > distortion ? > > For example, (Reference ->
> Sawtooth wave of constant period contains odd and even harmonics > Square wave of constant period contains odd harmonics > Triangle wave, (an integral of square wave) contains odd harmonics > > But, How is it possible that sinusoidal wave alone does not have any > harmonics or distortion ? > I searched the internet,but i did not find any link/pdf that talks in > detail about these . > Any ideas ? > > Thx in advans, > Karthik Balaguru >

It's a good question. Myself I'd say a triangle waveform looks like it should be the one to have no harmonics. But it's all down to how smoothly the waveform voltage changes. The triangle and square have significant 'shape' discontinuities during each cycle and these have the effect of creating harmonics. The sine wave although a horrible looking non linear waveform, is the one with the absolutely smoothest rate of change over all its cycle. (DC is even smoother but isn't a frequency :)

• posted

john jardine a écrit :

It's more a matter of definition. When you take the view of decomposing a waveform on a sine waves base, it is not abnormal that a sine wave has just one component on that base: itself. The contrary would be abnormal.

If you were to decompose a sine wave on a triagular waveforms base (which is as valid as the sine waves case), it'd had lots of 'harmonics' and a triangular waveform would have just the fundamental.

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Thanks,
Fred.```
• posted

"Fred Bartoli"

** No it is not - you posturing wanker.

** No it is not.

A sine wave uniquely has the property of no harmonics.

Unlike all other periodic waves, its shape is unaltered after passing though any kind of filter.

....... Phil

• posted

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Nice...```
• posted

... as long as the filter consists only of passive/linear components :-).

• posted

OK My filter is a full diode bridge; do you pretend that the output of that is a sine wave?

• posted

"Joseph2kook"