Hi Kai,

This is sort of what I'm wondering about. How often does anyone really need a broadband characterization of a capacitor (or inductor)? And if one does need such critical information, how much value will it be if measured independently of the intended circuit?

This question arose because I ran across an old lab report from undergraduate school that I thought was pretty cool. It was a lab exercise wherein we used a signal generator, a known resistor and an oscilloscope to measure the capacitance of a capacitor. It was a really novel use of an oscilloscope, and with a spreadsheet to do the calculations as the data are entered it would be fairly straightforward to characterize a reactive component over quite a band.

So I thought about writing up a short article about it for a website I'm preparing. On the other hand, I'm just not at all certain it will be of any practical value. As I asked above, how often does one need such data? On the other hand, that such data are needed so infrequently is precisely why most don't have an LCR or Q meter, and even fewer have a network analyzer. And that might make this technique worth knowing, just in case the need arises.

Joe