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Jeff Liebermann Jeff Liebermann is offline
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Default One last ESR question

On Thu, 23 Apr 2015 05:35:06 -0700, RobertMacy
wrote:

Or, you can use your soundcard and do any spectrum from 10Hz to around
91kHz, and actually get plots of Re(Z) amd Im(Z) vs Freq. I used my card
nad found a 'tracking' relationship between reactive impedance and the
loss in an aluminum cap! My whole career, that was something I never knew
existed [paid attention to]! But, found verified in an AppNote from AVX.
Very educational to 'play' with such an inexpensive instrument.


ESR is normally measured at 100KHz. A 192KHz sound card won't do
100KHz.

I'm more into the RF chacteristics of passive components which
requires a VNA (vector network analyzer). For example:

"Measuring Capacitor Parameters Using Vector Network Analyzers"
http://electronics.etfbl.net/journal/Vol18No1/xPaper_05.pdf
Notice on the first page that the authors redefine ESR as the residual
resistance at resonance. Sigh.

Oops. gotta run...

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