This is basically right. I just finished installing a 110' tower on land
that slopes pretty steeply -- over 30' elevation change from the downhill
anchor to the highest uphill anchor.
First, I determined the desired guy distances, angles and lengths as if the
tower would be on flat land. I had to push my guys out a little from the
nominal Rohn spec in order to accommodate the turning radius of an antenna
to be mounted on a TIC ring above the middle guy. Then I used a transit
level to determine the slope from the base of the tower to each anchor
location. I plotted the terrain slope on the graph paper and used that to
determine the anchor locations that would keep the guy angles as close to
Rohn spec as possible. For uphill guys, you simply find the point where the
flat-ground guy intercepts the slope. For downhill guys, you draw a line
extending the guy to the point where it intercepts the slope. Uphill guys
are shorter than they would be over flat ground, downhill guys are longer.
73, Dick WC1M
> -----Original Message-----
> From: Cqtestk4xs@aol.com [mailto:Cqtestk4xs@aol.com]
> Sent: Thursday, November 23, 2006 3:04 PM
> To: TOWERTALK@contesting.com
> Subject: Re: [TowerTalk] Guy Anchor Location - Hill
>
> After living in a state (FL) that resembles a table top, I am
> now facing the same sort of problem.
>
> I am going to tackle it as though all three anchors are
> entering the ground at a point 80 feet from the base. The
> actual points of entry will be either further away (if going
> downhill) or closer (if going uphill). I think the way to
> handle this is to be sure all three guy wires attach to the
> tower at the same angle...or at least pretty darn close. IMHO
> as long as the relative differences are not too big,
> adjusting the distance from the tower to accommodate the
> terrain accomplishes this.
>
> Now back out to sanding and painting the Rohn 65 that is
> going to be used for the project.
>
> Bill K4XS/KH6
>
>
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