Hi, Designing a 33' portable 80M vertical. Modelled it, and said I
needed a 37 uH loading coil around halfway up. Wound one using a 2"
cardboard form and #18 teflon insulated wire. My Z meter said it was
37 uH, upon placing in service, the resonant point was fairly close to
the design point on the antenna.

My question: I was hesitant to to put the coil in service because my
MFJ259B would not confirm the inductance value. It said the Z of the
coil was than 650 ohms or that L(X=0), all dependent on frequency.
I could never get a good indication of the Inductance. I suspect this
is due to self resonance of the coil, but don't know. I calculated
the Inductance of the coil given the F and Z reading on the 259B and
it came close to 37uH, but still (inductive reactance) X=0. Anyone
know what is going on?

Thanks,
Gary N4AST