"Roy Lewallen" wrote
I can assure the readers that all the effects I've discussed are
soundly
based on very well known principles.

====================================

Roy, you seem to have forgotten proximity effect.

If one calculates the Q of a coil from HF skin resistance of the wire
and from coil inductance, one gets ridiculously high values of Q.

Other producers of coil calculators appear to have forgotten this too.
That's if they were ever aware of it.

I have a coil, about 4 inches long, about 1.7 inches in diameter, with
about 90 close-wound turns of 1mm diameter wire, which has an
inductance of about 100 micro-henrys. The measured value of Q at 1.9
MHz is about 240.

This makes the proximity effect about 3.5 or 4 times the effect of
simple HF wire skin resistance. This is a large amount.

This is the first time such information has been appeared on a
newsgroup or published in bibles anywhere else. They didn't have Q
meters 120 years ago, in Heaviside's time, when such factors were
first considered.

My findings are incorporated in program SOLNOID3 which estimates Q
(and other characteristics) for coils of various dimensions. There
are, of course, other factors which influence Q which is a relatively
unimportant coil characteristic.

What do you do with Q once you have taken the trouble to find it? The
other more important things will already be apparent.
----
.................................................. ..........
Regards from Reg, G4FGQ
For Free Radio Design Software go to
http://www.btinternet.com/~g4fgq.regp
.................................................. ..........