After having a problem with the 75m bazooka I decided to put up a fan dipole for the winter. The bazooka, which was made of two pieces of RG-213 soldered in the middle, failed this fall. I believe the solder joint came apart inside the conduit body that it was epoxied into. I was looking at putting up a remote coax switch and running multiple bazookas. This gives me multiple bands on one feedline without the switch. It is resonant on 160m, 75m, and 40m. It also happens to work on several other bands as well. I can move quite a bit on 75 and 160, very much to my surprise.
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| Center spreaders, support, and feed insulator. |
The next two photos are of the wire legs, fiberglass rod spreaders, and strain insulators on the ends.
I cut down driveway reflectors to use the rods as the spreaders, they seem to work well so far.
Sep. 2016 Update:
After 5 years of service, I have a failure. Well, sort of. One of the dogs chewed a guy rope off and my daughter got into the wire with the tractor while mowing. This caused some of the fiberglass rods to split. The center insulators took the abuse, but I will have to take the entire antenna down to measure and replace the elements that got chopped and wound up in the tractor mower.
I am dreaming of building a support for my next wire antenna project. I have tried the wood and well it wont last at the beach. I can weld. I was thinking of stainless sch 10 or 40 with guy supports and use a top pulley for raising and lowering the wire for 40 meters. Will the stainless mast hav effect on the signal.
ReplyDeleteYeah, I have been horribly slow at getting to the blogs. Life happens....
ReplyDeleteIf the support is vertical and the wires mostly perpendicular to it like an inverted V or flat top dipole, no the vertical conductor(your mast pipe) really doesn't interact with the antenna.
I am curious though, what happens to the wood near the shore? Does it rot because of the high moisture? The pole I have up was taken down after 2 or 3 decades use as a power line pole.