Yo,
I think you're done. When I put up my various and sundry sizes of US
Towers I made sure that the base plate that sits
on the threaded J bars into the concrete was level by adjusting the big-ass
nuts that are under the plate. I could do this by not
grouting under the plate. I used a 4' bubble level along the various
horizontal planes on the base plate until the bubble was satisfied.
There is some movement between each section on these crank-ups so as
long as the base is level, the tower firmly affixed to the base
and the antenna is mounted somewhere close to its center of balance then
it'll be reasonably straight/vertical when it is elevated.
I doubt that utilizing technology that will give you level to 0.0001 nm
will help your tower's survivability.
What kills towers are big unanticipated winds, big falling trees, lack
of maintenance and varying degrees of operator's stupidity.
73 and I remain,
Lew W7EW
On Mon, Jan 2, 2012 at 11:41 AM, Gene Fuller <w2lu@rochester.rr.com> wrote:
> As most of us know, there's almost always at least a little breeze at 100
> feet , however Steve's problem with a crankup is only with 20 feet.
> Gene / W2LU
> ----- Original Message -----
> From: "K8RI" <K8RI-on-TowerTalk@tm.net>
> To: <towertalk@contesting.com>
> Sent: Monday, January 02, 2012 2:21 PM
> Subject: Re: [TowerTalk] How to Level a Crank-up?
>
>
> > On 1/2/2012 1:25 PM, Gene Fuller wrote:
> >> On a calm day, you could hang a string, with a small weight on the end,
> >> from
> >> the top of each tower leg. Gene / W2LU
> > It's easier to hand the string from the top of the tower, down the
> inside.
> > OTOH I have never found a day calm enough to do this with a tower
> > taller than 40 feet. I use the Transit level weight which comes to a
> > point.
> >
> > Even an what felt like calm days the string would move off to one side
> > and it was very difficult to detect. Around here those days are very
> > rare. With the 100 foot 45 G even on those hot sultry (suffocating)
> > calm summer days I find a light breeze at the top.
> > I used one of the laser transits, although a laser level would be much
> > cheaper. However some of then are barely good enough to square up a
> > small room.
> >
> > Mine is a guyed tower (45G) and the bottom two sections were carefully
> > leveled. Then the level was checked with each set of guys added. When I
> > got to the top it was just a matter of tightening the guys a 40 or 30#
> > at a time. So it went up straight.
> >
> > With a crank up you can only level it for a calm day. I think you will
> > find it will be surprisingly straight, except on really windy days and
> > those are when you want to crank it down anyway.
> >
> > 73
> >
> > Roger (K8RI)
> >>
> >>
> >> ----- Original Message -----
> >> From: "Steve Jones"<n6sj@earthlink.net>
> >> To:<towertalk@contesting.com>
> >> Sent: Monday, January 02, 2012 12:42 PM
> >> Subject: [TowerTalk] How to Level a Crank-up?
> >>
> >>
> >>> I want to level my new US Tower HDX-589. I put a 4' carpenter's level
> >>> on
> >>> all three legs of the base section and have levelled them. This is all
> >>> US
> >>> Tower recommends.
> >>>
> >>> Is there anything more I can do? I have heard of using two theodolytes
> >>> with
> >>> it fully extended. But I figure the sections must lean a bit due to
> the
> >>> clearances that allow them to slide past each other. I don't want to
> >>> tilt
> >>> the bottom section to compensate for that lean, since different antenna
> >>> loads or wind loads will probably make it lean different directions.
> >>>
> >>> With the bottom section leveled, am I done?
> >>>
> >>> 73,
> >>> Steve
> >>> N6SJ
> >>>
> >>>
> >>> _______________________________________________
> >>>
> >>>
> >>>
> >>> _______________________________________________
> >>> 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
>
> _______________________________________________
>
>
>
> _______________________________________________
> 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
|