On Jan 28, 12:28*am, David Nebenzahl wrote:
On 1/27/2011 7:06 AM George Herold spake thus:

I used your techinque to look at a 1000uF cap. *I used a DSO with a
bit of signal averaging. ('scope triggered from a sync output from the
generator) *I got something like 0.016 ohms at 100kHz. *Our SRS RCL
meter measured 0.014 ohms at 10kHz for the same cap. *and then 'lost
it's mind' at 100kHz. *(reported a negative capacitance.)

Perhaps you've stumbled onto the "anti-capacitor". Maybe you could
patent it ...

--
Comment on quaint Usenet customs, from Usenet:

* *To me, the *plonk...* reminds me of the old man at the public hearing
* *who stands to make his point, then removes his hearing aid as a sign
* *that he is not going to hear any rebuttals.

Hmm, Well I was thinking about this. Perhaps the RCL meter looks at
the phase shift to get the sign. The minus sign would indicate that
at 100kHz the 1000uF cap has passed through it's minimum impedance
point and is now rising up the other side and looking more inductive
to the driver.

(Just a guess.)
George H.