Try this, Chas: With the leads on the part being tested, take a reading.
Then, without moving the leads, short them and read leads-only
inductance. Subtracting lead inductance from the value previously read
will very often get you quite close to the REAL value. Some meters - and
that Elenco should be one - have an offset function, allowing lead
parasitics to be removed automatically. My B&K does.
You say your MFJ 259B is not accurate. It should be. In fact, at RF it
should be closer than the Elenco, which uses audio and misses the effect
of turn to turn parasitic capacitance. BTW, the 259B is capable of
reading inductance directly, rather than resorting to the grid-dip
option; its frequency calibration is good enough that detecting
resonance can be more accurate. though. To get that accuracy, you will
need resonating capacitors whose value are rather precisely known . Have
you tried, instead of dipping, detecting series resonance directly?
Cortland
KA5S
From: Charles Greene <[EMAIL PROTECTED]>
Elenco LCR-1810. It has a 200 uH sacle as the lowest scale, but it does
not read correctly and is off by a factor of 2:1 at low values of uH. I
need to read uH in the range of 2 TO 200 uH (HF inductors). The only thing
I have other than the Elenco is a MFJ 259B with the grid dip option which
is a pain to use and not that accurate either.
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