Howdy Arie and fans,

Dale W4OP, found the link to W4RNL dissertation on modeling insulated wires at
http://www.cebik.com/amod/amod50.html
which shows how NEC4 engine considers insulated wires.

Among other things on the page I have found that I was not of the rocker after
all, when I was talking about the "electrical length" of conductors used in the
antenna. I was "grounded" by some NG purists that IEEE dictionary or reference
books do not use or mention that term. To me it made perfect sense, just as
with coax and feedlines. If we are looking for the resonant or corresponding
electrical length of the "wire" we know that we can end up with different
physical length for the same frequency between the thick tubing and thin wire.
This is important especially when dealing with parasitic arrays, where resonant
or electrical length is important and physical length can be then derived from
it to maintain proper function of the array.

Here is what W4RNL 'splains also:
For a long time, antenna builders have been aware that insulated antenna
element wire has a velocity factor. The electrical length of an insulated wire
will be longer than the physical length to a degree that depends upon the type
and thickness of insulation. Expressed from a different perspective, a resonant
dipole for some given frequency and wire diameter will be shorter if the wire
is insulated than it will be if the wire is bare. How much shorter the
insulated dipole will be depends on the insulation.

So feel free to use the term, no need for royalties.
I feel not SoDumb :-)

Yuri, K3BU