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Before I had noticed that the 80 Meter Linearly Loaded Folded Dipole had become twisted in the wind, other local stations informed me that my signal was not getting out as well as usual. I simply attributed it to the fact that I was only running about 75 watts and the hot days of summer always seem to wipe out some of the signal strength. But after noticing the twist in the wires, I decided to build another 80 meter antenna. I had an old Bazooka dipole stored away, so I got it out and put it up. When I checked the resonance, I discovered it was at 15 MHz, not 3.75 MHz! Something was wrong, I didn't feel like wasting time with it, so I decided to make another one.
     There was some old RG6 coax lying around, and in mentioning what I planned to do, another Ham said that "old aluminum wrapped coax will not work as a Bazooka." Well, nothing like a challenge to get me going! All I needed was the velocity factor, the capacitance per foot of RG6 and the correct formula. Instead of finding this information, I happened upon VE3SQB's web site with several programs for automatically calculating the dimensions of various antennas, one of which was a coaxial dipole using RG6. So, I ran the program, cut the RG6 to the correct length, soldered all the appropriate points, went outside and put it up. I ended having to cut about a foot and a half off each end, but it works very well.

Bazooka1 Bazooka2

The left picture is the Bazooka antenna. I ran a thick rope from the top of a 30' tower to another 30' tower, through a pulley, and then down the side of the tower to a crank mounted at the bottom. Before cutting off the rope, I added another 30' of rope. This would allow me to put the rope in the crank and, when uncranked, the antenna would reach the ground. Next, I hung the antenna on the rope stretched between the two towers (the rope had two metal rings tied into it, spaced a little further apart than the length of the antenna The antenna was attached to these two metal rings so that it would not slide forward and bunch up in the center of the rope. In this way, there is no tension on the antenna.) I use a crank to tighten up the rope and this makes it straight between the two towers rather than hanging down in the center.

Here is a screen shot of the dimensions I calculated from the program by VE3SQB:

Bazookadimensions

Here is the resultant SWR plot. Not the best, but okay for now (I was aiming for 3.800 MHz resonance):

Bazooka

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80 Meter Double Bazooka