# Complex Waveforms

#### craig56

Joined Feb 27, 2007
1
I have a question for my HNC can anyone help

the question is

illustrate a complex waveform containing even and one containing odd harmonics, detailing ehich orders are prescent ?????:

#### Papabravo

Joined Feb 24, 2006
15,549
So what's the problem?

A complex waveform is the sum of two or more simple waveforms.
The waveforms we are talking about are sine waves.
Lookup the definition of harmonic and you're home free.

#### hgmjr

Joined Jan 28, 2005
9,029
You may want to review the material in the Mixed AC waveforms tutorial in the e-book section of the AllAboutCircuits website.

hgmjr

#### Steve1992

Joined Apr 7, 2006
100
What a coincidence; I was just going to post a question on Fourier, but I found this thread, so I put it here instead:

I just want/need to know the very basics.

Am I right with the following:

Symmetrical 50 Hz square wave.
w = angular velocity = 2pif = 314 radians.
E = peak voltage of square wave.

Fundamental peak voltage = (4E / pi)sin(wt)

3rd harmonic peak voltage = (4E / 3pi)sin(3wt)

5th harmonic peak voltage = (4E / 5pi)sin(5wt)

so on....

The sum would be 4E / pi(sinwt + 1/3sin3wt + 1/5sinwt....)

My math is piss poor, so I intend to K.I.S.S.

Steve

#### hgmjr

Joined Jan 28, 2005
9,029
The link I provided in my earlier reply in this thread provides the exact problem in it. You may want to compare your answer to the one they obtained.

hgmjr

#### Dave

Joined Nov 17, 2003
6,970
I have a question for my HNC can anyone help

the question is

illustrate a complex waveform containing even and one containing odd harmonics, detailing ehich orders are prescent ?????:
Are you looking for something along the line of the attachment. Showing even (real) and odd (imaginary) components at the 1st, 2nd, 3rd and 4th haramonics. I apologies for the sketchy drawing, I've just drawn it with my mouse!

Dave