I read in sci.electronics.design that John Larkin jjlarkin@highSNIPland
THIStechPLEASEnology.com wrote (in lr1c50ls8v4stqisn34rcd8eoc4bkqu4vo@
4ax.com) about 'Extracting the 5th Harmonic', on Mon, 15 Mar 2004:
spam.yuk wrote:

I read in sci.electronics.design that John Larkin jjlarkin@highSNIPland
THIStechPLEASEnology.com wrote (in qvrb50hvn0t1nj7kq5cako00bjrtis7nnr@
4ax.com) about 'Extracting the 5th Harmonic', on Mon, 15 Mar 2004:
On Sun, 14 Mar 2004 21:27:21 +0000, Paul Burridge
wrote:

On Sun, 14 Mar 2004 12:04:18 -0800, John Larkin
wrote:


Why not just bandpass filter the 5th from the square wave? Too simple?

I suggested this a while ago, but no one seemed very keen on that
solution for some reason.

Write down their names for me please, so I can remember to not hire
them.

The reason no-one seemed keen is that the OP's **complaint** was that
his 5th harmonic BP filter didn't produce any output.


So I guess Fourier was wrong; makes sense, with a French name like that.

No, what has emerged from the discussion is that rather small deviations
from a perfect square waveform can drastically reduce the amount of one
or more harmonics in the spectrum, and this probably is the source of
the problem.

--
Regards, John Woodgate, OOO - Own Opinions Only.
The good news is that nothing is compulsory.
The bad news is that everything is prohibited.
http://www.jmwa.demon.co.uk Also see http://www.isce.org.uk