"Roy Lewallen" wrote
EZNEC doesn't report time or propagation delay. If it's needed, it
must
be calculated from the reported phase angles.

Roy Lewallen, W7EL
===================================

EXACTLY! Roy, you knew exactly what I was hunting for!

The phase angle should indeed increase with frequency.
With a true transmission line the increase should be directly
proportional to frequency.

But the propagation delay, with a true transmission line, should be
constant versus frequency as it depends only on coil dimensions and
hence on L and C. The velocity factor should also be a constant.

When the angle is 90 degrees the coil is 1/4-wave resonant.
When the angle is 180 degrees it is 1/2-wave resonant.
The 180 degree frequency should be twice the 90 degree freq.

The differences between the 'measurements' and expectations, on the
basis of a true transmission line, can perhaps be explained by the
very small ratio of wire diameter to winding pitch. (Who would use
such a coil to load an antenna anyway?)

The ratio of coil diameter to coil length is large. Therefore
end-effect (as with an antenna wire) becomes quite important.

I have no idea what else may have been 'connected' to the coil when
inside EZNEC. Could it have affected measurements? Would it be
possible to 'measure' input impedance looking into one end of a coil
with the other end disconnected?

Regarding the calculated values of delay time there seems to be
something wrong. There is a simple relationship between phase angle
and length of coil and time. What was the formula used to calculate
propagation time? If the correct formula was used does this point to
somthing peculiar with EZNEC's own calculations?

Can't think any more.
----
Reg.