[TowerTalk] Help needed with Antenna Model

[Dave Sublette]

I am attempting to model the W6NL two element Moxon yagi for 40 meters.  I have a working file. It runs and gives perfect results. The software I am using is the “Antenna Model” program. I selected it because it handles the Moxon configuration while some other programs won’t.

I attempted to change the file using the diameters and length of tubing I have on hand.  My file will not run properly because I cannot place the source at element 1, center, as the correct file has.

My elements have 17 segments in the driven and director elements.  The W6NL has 19 segments in driven and director.  The “TEE” sections of both files are identical and placed at the same points on the driven and director.

Until I can get my file to accept placing source 1 at wire 1, center, I can’t begin to tweek my lengths to achieve the desire pattern, etc.

I have proof read until I am crosseyed and see no mistakes in my file. I have faithfully duplicated the placement of the TEES.  The only obvious place to find a error is what ever is causing my model to have 17 segments instead of the 19 in the original file.  I will continue to look there.

It has me stumped….

Anyone care to offer advice?

Thanks & 73,

Dave, K4TO

ps — the program will allow me to place source 1 at wire2, end1.  It will then run, but impedances are all off by a large factor.