[NJARC] Mega 328 Tester

[Mike Feher]

Leakage and ESR are two different phenomenon, that are often present
simultaneously, that degrade capacitor performance. ESR is Equivalent Series
Resistance and leakage is effective parallel resistance of a capacitor.
Leakage can be easily tested by just applying DC and measuring the current
drawn. This is why some of the older electrolytics run hot. ESR is in series
with the capacitor and has to be measured at an AC frequency applied where
the capacitors reactance is fairly low and calculable at the applied
frequency. The resistance in excess of the reactance is the ESR. ESR is more
of a concern in power supply filter capacitors and leakage is more of a
concern in coupling capacitors. 73 & a health 2016 - Mike  

Mike B. Feher, N4FS
89 Arnold Blvd.
Howell, NJ, 07731
732-886-5960