With the help of Jim Grissom (WD8RFW), we embarked upon an ambitious program to consider if his HF vertical, 4-band, antenna could be optimized. Whether it is actually optimized or not is somewhat irrelevant although it is known that our task will optimize the antenna for its 40 meter band. Our task to to see if we can shift the antenna’s resonance by a geometric-linear offset so that each of its 4 bands will be optimized.
The word geometric-linear is one of those two-dollar words so let us say a little bit about the word. Because the amateur frequency spectrum allocation traverses orders of magnitude in values, we can only address frequency spreads in a geometric fashion and thus the “geometric” portion of the word. But the “linear” would at first glance seem to neutralize the geometric word. The object of our endeavor is to shift the HF antenna’s entire resonance pattern by an offset that is linear in fashion though traversing magnitudes of frequencies. When you see what the effect is, you will understand what this is all about.
But let me add that I had earlier noted that some aspect of our endeavor is irrelevant. That is that our measurements showed that Jim’s Hustler antenna is already performing quite acceptably across all of its four bands. However, its performance is marginal on 15 meters. If our task improves his 15 meters performance, then we will have accomplished something.
In any case, this is a learning experience that Jim and I would like to share with the amateur community.
Please look through the rough draft document that I have written up below which describes our actions and measurements to this point.
