On 10/16/2014 3:29 PM, Brian Howie wrote:
In message ,
Lostgallifreyan writes
John S wrote in :

Yes, of course. And, with the free version of EZNEC, one must be careful
not to exceed the max segments allowed.


I've started reading the manual, I suspect there's little danger of
that.
At least with EZNEC+ 4 onwards, not sure about standard version. I
suspect
like curves built in segments in Sketchup, or the straight bars in the
chains
of the Clifton Suspension Bridge, the amount of fine tuning you'll get in
using more than about 24 segments for a catenary might be an exercise in
diminishing returns, and that even just 3 to 5 might be adequate, if the
deviation from straight is small.

I did a simple sagging 40m dipole on MMANA using the wire editor with
9 wires. I had a 3m sag in the middle . I ran the optimiser for best
match. The impedance worked out at 69 ohm and the gain was 2.06dBi. The
model reported a lobe elevation of about 8 degrees. There was a
vertically polarised component at 90 degrees to the horizontal lobe at
-15dBi.

You'd expect something like this to happen since there is part of the
antenna in the vertical plane.

Brian GM4DIJ

By the way, Brian, do you have data of the non-sagging model for
comparison? Don't do it unless it is fun for you. The data looks just
about the same for a non-sagger anyway. A comparison would show the
small differences.

Super work! Thanks.