On Mon, 30 May 2011 10:05:12 +1000, "Phil Allison"
wrote:

** Seen this ??
http://www.youtube.com/watch?v=zEA5MfllPdg

Kills 9V batteries. Otherwise, good price and good unit with many
features that I'll never use.

All you need to do is compare the ESR reading of a known good electro of
about the same ratings and size with the one under test. If the one under
test has say 5 times more ESR - it is useless or about to fail.

Often, with worn out electros, the ESR may be over 100 ohms.

That will work, if you happen to have a known good and identical
capacitor handy. I have a fair collection of electroltyics but not
every value and voltage.

The problem with the Extech 380193 Handheld LCR meter is that it will
measure ESR at 120Hz and 1KHz. ESR is usually measured at about
100KHz. Dave Jones mentions this at about 12-13 minutes into his
video. This is because electrolytic cazapitors exhibit a minimum ESR
around 100Khz.
http://www.amccaps.com/leaded-capacitors/switch-mode-ceramic-capacitors/esr-vs-frequency.html

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558