Oops, somehow the word "Boom" got into this thread... "Boom" is the
wrong term - changing the boom length is not the same as changing the
turning radius (in most cases!)
In my original post (bottom) I said it correctly: adding one foot to
the "turning radius" - not adding one foot to the "boom" - and
recalculating gives one foot of clearance. We *were* talking about
"turning radius" all along anyway, but I just want to be clear.
-Mike
N2MG wrote:
> I disagree. If you push the guy out from the tower by one foot
> at the spot where the boom would otherwise hit it,
> you've added one foot to the clearance.
> To push it 1 foot away at the example's 60-foot height, the
> anchor moves 5 feet away.
> KK9A wrote:
> > Adding 1' to the boom does not give 1' of guy clearance unless
> > the guy runs straight up and down. Guy clearance should be
> > measured perpendicular to the guy. In this case for 1' of
> > clearance the guy would be at a 29 degree angle and the anchor
> > would be 136' from the base of the tower.
> > N2MG wrote:
> <SNIP>
> > > This makes guy anchor distance x = 125' for zero clearance.
> > > To get 1 foot of clearance we change the 25' turning radius
> > > to 26' and get: 130' Then there's ground irregularities and
> > > guy wire sag so you may opt for more minimum clearance.
> > > Lower the antenna 5 feet and the 1-foot clearance anchor
> > > spacing is only 98 feet Big difference. Of course, if you
> > > have the room and the EHS...
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