I'm planning to add a second C-3, fixed on Europe, 28 feet below my top
antenna, to my 100 ft Rohn 25 tower this summer.
My top set of guys have 21-foot fibreglas insulators at the top end, but
are unbroken from there on down. Modeling suggests that they will really
mess up the pattern of the stack, not to mention when using the lower
antenna alone.
I plan to go over to totally non-conductive guys for the top set, and move
my insulators down to the middle set. Question is, is Phillystran the only
practical option? A few years ago, some guys in PVRC bought a large
quantity of Polygon(?) fibreglass guy rod, which I understand is only about
1/3 of the cost of Philly, but as I recall there were minimum quantity and
handling issues. Can anyone enlighten me on this option?
Second, since I plan, initially at least, to fix the lower antenna on
Europe, it seems as if just about any 2" steel tubing will do for a mount,
simply rotating the boom-to-mast clamp on the C-3 to attach to a horizontal
tube. If this is how it's often done, the question is how best to attach
the tube to the tower. Would it work to U-bolt it to one leg and one
horizontal tower rung, or should I plan on something like an accessory
shelf, u-bolted to all three legs, with the tube in turn u-bolted to the
plate?
73, Pete Smith N4ZR
n4zr@contesting.com
Loud is.
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