In a message dated 99-08-21 10:05:51 EDT, n2rd@arrl.net writes:
> Commenting on Loos tension gauge:
>
> From: Ron Youvan <ka4inm@gate.net>
> > A cheaper way is to measure the droop (at mid-span) altho I don't know
> how to calculate the correct > value, it is another way to do it.
>
> The calculations would be harder as the guys are not horizontal. The the
> biggest issue is:
>
> How would you measure the droop at mid-span?
>
> Back to square one?
Yes, there's more than one way to measure guy wire tension. The easiest
is the direct method where you use a tension dynamometer or strand or Loos
tension meter. The Loos is $59.95 - the other two are $900 and $2300
respectively.
There are two indirect methods you can use. One is the Pulse Method
where you give the guy wire a sharp jerk (or swing) and you measure the
return with a stop watch and crank the time along with the total weight of
the guy, the guy length, vertical and horizontal measurements and some other
data into a formula. The other indirect method is the Tangent Intercept
method where in addition to much of the aforementioned information you need
the guy angle at the anchor (probably best done with a transit) and, again,
it's all cranked into a formula. These methods are obviously used for TALL
towers with BIG guy wires - not your typical ham installation. More info and
the formulas are in the TIA-222-F "Structural Standards for Steel Antenna
Towers and Antenna Supporting Structures".
The obvious accurate, quick, inexpensive and *only* way to measure ham
tower guy wire tensions is with a Loos.
Cheers, Steve K7LXC
Champion Radio Products
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