Re: Nationalized Health Care Preview?



Michael Stemper <mstemper@xxxxxxxxxxxxxxxx> wrote:
nospam@xxxxxxxxxx (Paul Ciszek) writes:
I tried setting up some lowpass and bandpass filters using only
inductors and capacitors in Excel, including this one:
http://upload.wikimedia.org/wikipedia/commons/thumb/b/bd/Bandpass_Filter.svg/300px-Bandpass_Filter.svg.png
...but I get some weird results.

Why bandpass rather than exclusively lowpass? You don't want any band
to pass, right?

That bandpass filter works great if the load is just right, but
if you don't load it enough, it actually *enhances* the wrong
frequencies rather than filtering them. Weird. I'll check the
math again when I get the chance.

It's a resonant circuit on the frequency you want to supress? If so,
I can easily see why tiny changes in the input would change it from
destructive interference to constructive interference.

I'd just put lots of big capacitors in parallel with the line, and
lots of big inductors in series.

If I recall correctly, all that you need to deal with is the 6n+/-1
harmonics.

Any time-symmetrical waveform will only contain even harmonics.
--
Keith F. Lynch - http://keithlynch.net/
Please see http://keithlynch.net/email.html before emailing me.
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