But isn't that what the house brackets are for?
> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of Jon
> Sent: Sunday, April 01, 2012 12:31 PM
> To: towertalk@contesting.com
> Subject: Re: [TowerTalk] Rohn tower installation specifications
>
> The 2x2x4 chunk of concrete is called ballast.
> Similar to the keel of a sailboat...helps to keep it upright.
>
> On Sun, Apr 1, 2012 at 2:24 PM, Dave Cook <wa0ttn@netdave.com> wrote:
>
> > Hi guys, I'm in the process of relocating my 35' freestanding Rohn 25G
> > tower after 8.5 years on the air. I figured this time I'll bracket it
> > to the house, which is what I should have done in the first place. But
> > I've run across a few problems with the Rohn specifications:
> >
> >
> >
> > 1. The tower will be bracketed to the house mid-way up and also
near
> > the top of the tower with an eave bracket. The specifications for the
> > brackets "must support a minimum horizontal force of 815 pounds". I
> > can't find any calculations for how they came up with this number. And
> > it seems very excessive for a modest 35 foot tower bracketed in two
places.
> >
> > 2. The specs also state that the base must be a "fixed base",
rather
> > than a pinned base. Again, in this case I don't understand why a
> > pinned base wouldn't be sufficient for a well-bracketed tower. Why
> > would the base experience any lateral loading?
> >
> > 3. The specs also state that the base has to be the same 2x2x4
feet
> > of
> > concrete that was spec'ed for self-supporting and guyed towers. In
> > this case I can understand somewhat having a solid chunk of concrete
> > for the thing to rest on, but the entire weight of the tower and
> > antenna will be, by my calculations just a little over 200 lbs. It
> > doesn't seem to me that it needs a 2000 lb chunk of concrete to keep
> > that from sinking into the soil.
> >
> >
> >
> > So in short, I'm just wondering if Rohn is simply CYA'ing themselves,
> > or are these specs really to be taken literally?
> >
> >
> >
> > Thanks and 73,
> >
> > -- Dave WA0TTN
> >
> > _______________________________________________
> >
> >
> >
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