I first built this antenna about 1980 and it did an excellent job. I wanted to get it higher so I used 1&1/4 wave length on the coax to each element. I had no front-to-back with this length so I added another 1/4 wave of coax for each element. I could have obtained the front to back with the odd wavelength but I preferred adding an addition 1/4 wave length since I had more experience with even wavelength coax. The design is as follows: The elements should be cut for 100-150kc below the frequency you are looking for. For example, if you want it to operate at 7.2mhz then cut the elements for 7.1mhz.This accommodates the mutual coupling between the two elements. The coax should be cut to a multiple of 1/2 wave length at 7.2mhz unlike the element length mentioned above. Pay attention to the velocity factor. Symmetry is paramount for this system. The switch I use for the system requires three tee connectors to accept the two coax from the elements and the other side of those two tee connectors is for the phasing line. The third tee is for the coaxial balun as shown in the illustration attached. A tee connector is also required at the rig. The switch does not ground either feed line, given RF is fed to both elements. Another applicable type of phasing would be the L/C network. I have found the antenna to be very broad banded. The element balun is a 1:1 current balun for each element. My system is at an average of 60’ elevation.

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