I can't believe you guys are still hanging in there with us on this
tower/antenna project. We think we may see some light at the end of the
tunnel. (yeah I know, it's probably a train)
You know how 'some' of us Ham's are... cheap. Well in the process of
being niggardly, we just may have severely narrowed our chance for
success. Two very valid points have been brought to our attention.
First, is how the guy wires are broken up and at what lengths. Second is
the feed point being above the ground radial system by 4 feet.
We'll address these issues separately.
Guy Wires. There are four sets on this installation. No anti-toruqe arms
were used so the first insulator is approximately 4-5 inches away from
the tower.
Set 1. Attached on tower at 26'-0" level. One insulator used at the
tower. Length of non-insulated guy, 79'-0"
Set 2. Attached at the 56'-0" level. One insulator used at the tower.
Length of non-insulated guy, 92'-8"
Set 3. Attached at the 86'-0" level. Two insulators used. Length of
non-insulated guy, 84'-0"
Set 4. Attached at the 116'-0" level. Three insulators used. Length of
non-insulated guy, 75'-0"
We are laboring under the idea that resonant guy wire problems are
either 1/4 wave length long or odd multiples thereof. Since none of the
above lengths fall into that category, we assumed we were ok. Note: The
nearest tower is 75' away. It is only 46' tall with house bracket... no
guys.
Feed Point: At this point, we don't see how we could avoid (or change)
the way we are having to feed the tower. The tower insulators are
approximately 4 foot above ground level. The ground radials are attached
below the feed point by some 3'-6". Again, we assumed this few feet of
section, grounded via 8' ground rods and the ground radial system,
wouldn't affect the over all performance. Heck... what do we know!?? It
may very well be a major problem. Anyone care to weigh in on this?
Let me first to say thanks for the bandwidth on this subject. Amateurs,
as a whole, are a studious bunch with a wealth of knowledge and infinite
experience. We even had one gracious individual that has offered to
drive to this location, on his on dime, to help us out. Wow!
Anyway, thanks for sharing your comments and ideas,
Steve AB5MM
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