Re: Cap testing

If you were using current through the cap to drive X and voltage across 
the cap to drive Y, wouldn't a "perfect" capacitor (i.e. - no inductance) 
give a circular trace since current leads voltage by 90 degrees?  Stray 
inductance would change the phase and distort the circle into an oval 
shape.  Only at resonance (or with a pure resistance) would the trace be 
a straight line.

Steven Roys (sroys-at-radiology.ab.umd.edu)