On 30 Nov 2004 12:37:57 -0800, Mike Silva wrote:

Duncan Munro wrote in message .. .

The metal film 33R measures 6.5uH and the oxide 22R measures 4.5uH on the
aade.com meter. Both values (if the readings are correct) would represent
a high ratio of X to R at HF frequencies...

I wonder, though, if the AADE meter is not getting confused by the
resistance of the resistor. The fact that the measured inductance is
just about proportional to the resistance might be evidence for that.

Mike, I think you've hit the nail on the head. To be fair to AADE, they
warn that the 'Q' of the inductor has to be reasonable to get a sensible
measurement.

The kind of measurement frequencies we are talking about are in the order
of 700kHz. At that frequency, the inductance of the 'indicated' 4.5uH is
19.8 ohms, not a million miles from the 22 ohms of the resistor itself -
this is not what I would call a reasonable 'Q' value. Fair play to AADE,
it's designed to measure the inductance of inductors, not other components
;-)

--
Duncan Munro
http://www.duncanamps.com/