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The theory behind this antenna is that you have a folded dipole cut for the low end of 80 meters. You then add a wire cut for the upper end down the middle of the folded dipole but not attached to anything. This creates a double hump in the SWR reading which broadens the antenna. I doubled the spacing of the line (from 12" to 24") and used heavy #12 wire under the assumption that the heavier the better. Well, this made it too heavy to be used in the sloper configuration, and it hangs down in a gentle curve from the highest point to the lowest point. I plan on rebuilding it with lighter wire (flex-weave) and strengthening the end and middle spreaders by using fiberglass fence posts.

LLFD5a LLFD2 LLFD6a

The left picture is the left (lower - about 30') end of the LLFD. Note the plastic CVPC pipe used as spreaders and that the center wire is not attached to anything. The center picture shows the feed-point of the antenna using ladder line. The ladder line is caught under a tree limb and is pulling the wire. The picture on the right shows the not so gentle curve up to the 80 foot level on the WiFi Tower as well as the twist in the wire half way up.

I have included an illustration from the QST article from which I took the design ("A Wide band 80-Meter Dipole" by Rudy Severns, N6LF) so you can see how it is supposed to be constructed:

llfd

        Below is an SWR plot of the antenna as it is presently constructed. About 250KHz spread with less than a 2:1 SWR. Note that there is no double hump when the wires are twisted. (There used to be a double hump!) When I rebuild it, I will post another SWR plot. But first I have to get up my nerve to climb to the 120' level on the tower and untangle the rope so I can lower the antenna! It has been about 15 months since I broke my left arm (it was in a sling for 6 months) and it's strength is only about one-third of my right arm. So, I'm a little leery of climbing right now!

               LLFDwithtwist

UPDATE: I climbed the tower, released the rope, got rid of the twist, and pulled the antenna up higher (about the 100' level). Here is the resultant SWR. Much better, (almost 400 KHz range below 2:1 SWR) although the double hump is not very noticeable. I also am barely able to stand up after climbing. It was not my arm but my legs that I needed to worry about!:

LLFDb

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80 Meter Linear Loaded Folded