Reg Edwards wrote:
I know how EZNEC calculates propagation from straight wires. It does
it very well.

In your last posting, you asked "How does EZNEC make its calculations?"
Wow, you're a quick learner.

But do you know how it calculates the inductance of coils?

Yes. A model of a coil is constructed out of straight wires, making each
turn polygonal. A wire containing a source is connected from one end to
the other and, providing that the coil is short in terms of wavelength,
the reactance seen by the source will be that of the coil at the test
frequency.

How long has it been able to do this?

An automated helix creation feature was introduced in v. 4.0 two years
ago this May. It has always been capable of doing the calculation, but
until v. 4.0 the user would have had to calculate the wire end
coordinates with an external program and import them into EZNEC.

The free demo version has this feature. You can create any size helix
with it to see how the feature works. You won't, however, be able to
calculate its inductance with the demo program due to the segment
limitation.

As I've pointed out before, EZNEC won't account for proximity effect, so
reported loss will be optimistic if the turns are spaced very closely.

Roy Lewallen, W7EL