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However, I intend to mount my UHF antenna permanently outdoors exposed to the elements, so I had to do I did what I did due to the following considerations:
a. The parts exposed to the elements will only be the antenna and an RG58 connection with the end filled in with waterproof compound
b. The lead in wire is an exact (n x lambda/2) electrical length, so that the impedance seen at that point will be the same as at the antenna feedpoint.
I did it this way because my network analyzer which allows me to get an accurate (n x lambda/2) electrical length determination easily.
c. I then place the matching circuit at the end of this RG58. This matching circuit is sheltered within the building.
d. To this matching circuit, I then connect my RG213 for the long 20m+ run to my rig.
e. One last point: The vertical section is not lambda/4 by rather longer. I made it longer than necessary and then clipped it while watching the S11 on the smith chart. My prime concern was to get the S11 as close to the center of the smith chart as possible. This is to keep the "natural" Q as low a value as possible so that after matching, the whole (antenna + match + connecting cables) will be as broadband as possible.
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