Drew comments:
>In 1992 I put up a 58' foldover tower at my new QTH, and
it has proved to
>be a nice antenna support. Living out in the country, I
found that using
>Phillystran for a second set of guys at the top keeps the
top from moving
>around in the wind we get out here (I am 10 miles north of
Champaign).
>73, Drew
I've noted that in the older Rohn literature, safe antenna
loads were specified for the three stock heights of the #25
foldover (48/58/68 ft) when guyed at the hinge only, and
when guyed at the hinge and apex. Current info requires
guying at both points no matter what the load.
I plan to go with Philly also, at least for the topmost 50
feet of the apex guys. Maybe for the midpoints as well, as
I tend to experiment with a lot of wire array
configurations hung off of anything from my 10 ft pear tree
to the Rohn, when it goes back up. Not cheap, but I need
to purchase new cable anyway. Short Philly sections, with
grips and thimbles might even make reasonable guy
insulators, but I haven't compared the costs yet when all
the hardware is taken into account..
I tend to believe strongly in the use of the Rohn guy
bracket, with torque bars where applicable. With four way
guying, I'm not sure if use of the 120 degree spaced guy
brackets and bars would provide the desired anti-twist
forces, with two guys tied to the end of one bar. This
would be applicable at the apex only, as I see no easy
method to fabricate an anti-torque assembly to fit the
hinge point. Any thoughts, or is this really overkill for
a foldover with no more than 8 sq ft topside and a short
mast?
73! - Mark
----------------------------------------
Mark Shaum K9TR
mashaum@fcg.net
Central Illinois Grid EN50
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