Re: Accurately measure C of electrolytic capacitors ?

From: Jamie (jamie_5_not_valid_after_5_Please_at_charter.net)
Date: 02/07/05 

Date: Mon, 07 Feb 2005 13:06:51 -0800

gmv wrote:

> Look more closely and tell me what can be done
> because I am at at a dead end.
> The noise is horrible above 2Hz I really
> need a filter that has a precipitous
> dropoff between 2 and 3 Hz in order get the
> gain to see anything worth watching.
> The phase distortions are terrible too
> but if I want to see a meaningful picture i have
> no other choices I know of. I have tried just about
> everything under the sun and these BP filters seem
> the very best for me and my location.
>
> The last three filters simply help to steepen
> the high rolloff so i can get more gain at
> the lower without being swamped by noise.
>
> The Earthquake people want me to look at
> .5 to 2Hz but that just is not possible for me
> unless I can roll 3 Hzand above -24db from what i get at 2Hz.
> I need a miracle filter that does not exist.
>
>
>
>
  have you thought of looking into doing some FFT (DFT) code?

  i don't know exactly what your doing but, its also possible to
to mix your input signal to generate a much higher signal.
  something like the use of a LM1496 comes to mind.

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