I'd appreciate and welcome reports from anyone who finds a significant
difference in insulated wire results between EZNEC and NEC-4, in the
region where both should be accurate (typical wire insulation values).

Roy Lewallen, W7EL

Owen Duffy wrote:

Roy, I went back and re-read Cebik's notes about the way in which the IS
card is processed vs using and LD card to add inductive loading. He
passes on an explanation:

===quote
In calculating the E-field for each segment in a model NEC calculates a
"cosine" component, a "sine" component, and a "constant" component. NEC
then sums the three fields to arrive at a total field value for each
segment.

LD commands modify the "constant" component of the E-field calculation,
whereas IS commands (in NEC-4) modify the "cosine" component. As a
consequence, any workaround formulation will result in satisfying only a
limited range of geometries.
===equote

It was with this in mind that I chose to head down the NEC4 path.

Owen