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Arie de Muynck[_3_] Arie de Muynck[_3_] is offline
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Default Step Recovery Diodes - a blast from the past...

On 2019-06-12 18:05, Jeff Liebermann wrote:
On Tue, 11 Jun 2019 17:17:41 -0700, John Robertson
wrote:

I use an ESR meter for things besides caps, this chatty one that goes
down to 0.001 ohms is handy for finding shorts between traces, and other
jobs, not just testing caps. Maximum is around 90 ohms.


Yet another idea. Most supercaps have an extremely low ESR. For
example, Murata claims 40 to 300 milliohms (measured at 1KHz).
https://www.murata.com/~/media/webrenewal/products/capacitor/edlc/techguide/electrical/c2m1cxs-053.ashx
Ask Bob Parker if he can build something to test those. I have no
clue how to build probes with that low a contact resistance. Fat
copper wires with silver contacts? I don't have an immediate
application or market, but I keep running into supercaps with no way
to test them for anything more than capacitance.

One would use Kelvin connections - probe resistance is not a major issue
then.
https://en.wikipedia.org/wiki/Four-terminal_sensing

Arie