I have a geometry editor that I use for some things, although being a math person, I generally do the math myself unless what I need is big, or complex. Four radials offset 45 degrees from the X axis and Y axis isn't hard for me, I just use the Pythagorean Theorem. I've used far more complex equations than that in previous models.. I can enter formulas into 4Nec2 that will make a shape and the size of an object. I don't have to go into a geometry editor and make the item again at a new size, I just change a variable. I have made coil based loads with said tool, it was very useful there. When I made the model of my SUV, I made the grids in the model with said editor, and positioned them so that when I put the grids in a single file they would line up properly. It is a powerful tool, and I can use it well, I just prefer not to when I don't have to.
I've used it in two scenarios, a five foot antenna as a loading for a 1/4 wavelength antenna in various configurations, and in a 5/8 wavelength antenna to tune it to be a 3/4 wavelength antenna electrically.
For the five foot length antenna, linear loading was more efficient than any use of a coil or cap hat, although not so much that you would notice over the other loading methods. That being said, I also wasn't trying to use it to resonate a 40 meters signal on it either. Its biggest downfall is the fact that is skews the pattern of a vertical antenna, one side has more gain than the other.
When it comes to the 5/8 wavelength antenna, the model with the horizontal linear loading system skewed the pattern the least, and it was pretty close to a co called "perfect" SWR match with no modification, well within use able range, the only issue is like the five foot antenna model there is still skewing in the radiation pattern. I modified that model for my first build of the I-10K/Shockwave antenna because it looked so similar, and that model was a success for me as well.
Linear loading is a neat trick, and in some specific cases is as good as it gets, but for vertical antennas it just isn't generally practical, most of my successful model designs would be a pain in the backside to implement physically, especially in a mobile environment for the smaller antennas. This combined with the fact that compared to other loading methods, most people just don't seem to understand how linear loading works.
If I put up a horizontal antenna in the limited space that is my back yard, it will be linear loaded, fed with ladder line, and run directly to an antenna tuner. The goal would be to make the antenna use able, and perhaps as effective as possible, on as many HF bands as possible. I just don't see it being widely used elsewhere, except perhaps some yagi designs.
The DB
