is second harmonic practically zero

[avlsi]

Is second harmonic practically zero. what is the typical value ? is it arounf (0-2) or else in the order of 0.001

Does that turn out to be in -ve on the dB scale.

 

[v_c]

Second harmonic of what type of waveform are you referring to?

If you have a perfect sinewave, yes the second harmonic is exactly zero.
If you look at an outlet on your wall, you should have a pretty good sinewave and you will have some harmonics but yes, the second harmonic in that case should also be very small.

Let's say you have a sinewave and you put it through a full-bridge rectifier. The output of the full bridge rectifier are waveforms that look like the waveform on the right.

That rectified waveform on the right will have a substantial 2nd harmonic, it will also have a dc value. However, the rectified sine wave will not have any fundamental frequency components. Fundamental frequency being the frequency of the input sinewave (on the left).

Best regards,
v_c

 

[keith1200rs]

A sawtooth waveform has a lot of second harmonics. With a 1V peak amplitude (2V peak-peak) the output is 0.64 fundamental, 0.32 second harmonic I think.

Keith.

 

[permute]

for a periodic waveform, even-ordered harmonics correspond to the symmetric portion, while odd-ordered harmonics correspond to the anti-symmetric portions. Most common test signals have no intentional even-ordered harmonics. PWM signals with a duty ratio other than 50% will have both even and odd harmonics.

If you want test signals with lots of even harmonics, you should aim for signals that are periodic, but lack any obvious symmetry.

 

[sinoo_jahagirdar]

Thanks keith..ya i have simulated all the waveforms (incl. sawtooth waveform) using fourier series.Got the 2nd harmonic value but practically i need to generate sawtooth waveform to synchronize with the mail ckt...

thanks for the reply.

---------- Post added at 05:55 AM ---------- Previous post was at 05:52 AM ----------

thanks . will try it n cme back 2 u soon for further doubts : )

---------- Post added at 05:56 AM ---------- Previous post was at 05:55 AM ----------

thanks . will try it n cme back 2 u soon for further doubts : )