The right word is "inductance." One of the most fundamental principles
of electrical circuits is that "pure" components -- that is, a coil that
has ONLY inductance, a capacitor that has ONLY capacitance, a resistor
that his ONLY resistance -- do not exist in the real world. All real
components have "stray" electrical elements due to their physical
construction. Resistors have small values of inductance in their leads,
and may have a tiny amount of capacitance in parallel. If you measure
at DC or at audio frequencies you won't see the inductance, but if you
measure at higher radio frequencies you will see a higher value of
impedance added by the inductance of the wire leads.
Inductors (coils) have some resistance in the wire used to wind them,
and capacitance between the turns of the coil. If you measure the
inductor at low frequencies, you see only the inductance, and perhaps a
small value of resistance. But if you measure at higher frequencies, the
capacitive reactance and inductive reactance are in parallel but of
opposite sign, so they partially cancel, and the apparent value of
inductance increases. If you go high enough in frequency the inductive
reactance and capacitive reactance will be equal, that's resonance, and
the inductor looks like a high value resistor. Go even higher in
frequency and that inductor looks like a capacitor.
Recent editions of the ARRL Handbook have an excellent discussion of
these concepts, and are a great place to learn electronics concepts.
Thank Ward Silver, N0AX, editor of recent Handbooks for his clear,
easily understood style of technical writing.
73, Jim K9YC
Though I closely adhered to the manual, the measured inductivities are
almost twice as high than the values stated in the manual (on the
parts list in appendix A).
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