Put up a temporary steel mast or ginpole clamped to a tower leg at the top
and tram with it. You will still need to back guy if there is much of an
angle involved. I would not risk the mast.
Chuck W5PR
On Sun, Mar 13, 2016 at 5:16 AM, Stan Stockton <wa5rtg@gmail.com> wrote:
> Steve,
>
> If you want to tram the antenna, in this case I would consider moving the
> top set of guy wires about 5-8 feet lower than where they are now and
> tighten them as if that's where they are supposed to be attached. Tram the
> antenna to the tower instead of involving the mast and then move it up onto
> the mast. Move the guy wires back up to where they were originally.
>
> You may want to remove all the elements that are within easy reach from
> top of tower and put them back on once the antenna is in place.
>
> 73... Stan, K5GO
>
>
>
> > On Mar 12, 2016, at 7:18 PM, Steve K7AWB <k7awbgoog@gmail.com> wrote:
> >
> >
> >
> > I have an aluminum mast (which is 2” OD and 0.25” wall and about 11
> feet) out of the flat top of the Rohn 25. Already I have a M2 17-element
> 2-meter yagi at the top of the mast. Below that antenna, and right above
> the flat top plate of the tower, I want to put my Force 12 5BA 5-band, 15
> element yagi.
> >
> >
> >
> > With my other tower, 90 feet of Rohn 45, we put up a 6-element Force 12
> Mag 620 the first time by simply dropping each of guys and reconnecting
> once the antenna was above each guy point. The second time we put it up,
> after balun replacement, we used a friend’s tram line and back-stay – of
> course the mast was 2” OD and 0.25“ wall and heavy!
> >
> >
> >
> > I don’t think I want to chance the Rohn 25 at 102 feet with that
> drop-the-guy process.
> >
> >
> >
> > So the question is : will a tram line work or will I bend the mast?
> Even using a back-stay might cause undue pressure and bend the expensive
> mast. And a bent mast does not rotate nicely.
> >
> >
> >
> >
> >
> > Steve K7AWB
> >
> > Nine Mile Falls, WA
> >
> > DN17es
> >
> >
> > _______________________________________________
> >
> >
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|