I have a Loos PT-2 that I use to measure and adjust the tension of the
pull-down cable on my U.S. Tower MA-770MDP. It works well for that.
But what about measuring tension on types of cable for which the Loos is not
designed? My new AB-577/GRC military surplus portable mast has three sets of
1/8" stainless steel guys. The installation instructions simply say to "make
sure the mast is vertical and the guys are taut". I ended up tensioning the
guys so that there was no visible slack, there was some (but not a lot) of
"tightness", and the mast didn't move when a guy was grabbed and shaken
vigorously. The guy tension adjusters (called "snubbers") have a sort of
self-limiting feature -- they're designed to be tensioned by hand and
there's only so far you can turn them.
The mast looks quite sturdy in a 35MPH wind, and I'm sure the guys are not
so tight as to risk their breakage or compression damage to the mast. I
tried to make the tension as equal as possible, but it's hard to know. Does
anyone know of any measureing devices or "rules of thumb I can use to set my
mind at ease about this.
73, Dick WC1M
----- Original Message -----
From: <K7LXC@aol.com>
To: <n2rd@arrl.net>; <towertalk@contesting.com>
Sent: Saturday, August 21, 1999 11:18 AM
Subject: Re: [TowerTalk] tensioning guys
>
> 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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