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[TowerTalk] Rohn 25 vs 45 ?

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Subject: [TowerTalk] Rohn 25 vs 45 ?
From: km1h@juno.com (km1h@juno.com)
Date: Tue, 6 Apr 1999 01:29:10 -0400


On Mon, 5 Apr 1999 11:51:23 -0400 "Dennis Shoaf" <dshoaf@Mondobaking.com>
writes:
>
>I am in the planning process of putting up a 130' tower in NE Alabama. 
> I
>will put up a M2 3 ele 40 mtr yagi atop.  I want to put up Rohn 45, 
>but my
>budget may not allow it (only 3k in budget).  Can I safely put that 
>type of
>Ant. @ 130' with Rohn 25, if I follow all of Rohn guying specs and not 
>do
>any potential damage to the tower or worse.  Any and all 
>advice/suggestion
>are highly appreciated.

Well I wont comment about published Rohn specs but I had a KLM 4el 40M
and a 4el CC for 10M 10' above that on 140' of 25G for 5 years with no
problem other than rotators. Also had 3 other CC 10M and 2 CC 15M ( all
modified to W2PV-4 specs) in fixed positions at various heights

Used 5 levels of 1/4" EHS guys with torque arms and the anchors were out
a full 75% of tower height. The tower sat on a concrete base plate and a
single pivot pin.

Survived some mean winds including 90 mph hurricane gusts. When it came
time to move everything came apart as easy as it went together. Heck,
Charlotte, KQ1F, was at the top during the dismantling!
Ten of those sections are in use at this QTH with almost as heavy a load
for the past 9 years. 

Now, would it survive in 'bama the next time a big blow comes ashore is
anyones guess.
I've been told by more than one PE that Rohn 25,45,55 is capable of
roughly 2.5 times published ratings.

One procedure that I do use that I rarely see mentioned is the use of a
transit for erection.  I'll spend that extra hour or two getting
everything absolutely vertical and as close to equal guy tension as I
can.

>
>One strange question.  Does Rohn make a 45/25 Reducer ? 

Yes, Big bucks.  You could easily build one utilizing a standard 45 flat
top section and a 25 concrete base plate. That would also be a good place
for a guy station.


 Where as if 
>I
>wanted to go up 70 ft with Rohn 45, then rest of the way with 25 ?  
>May
>seem strange or may not serve any other purpose other than saving
>money......Agn, any opinions are appreciated......

My opinion only Dennis, I have no intention of getting involved in long
winded dissertions on physics, specs, building codes, etc. I just do what
works for me....

 73  Carl  KM1H


>
>Dennis, W4DWS
>
>
>
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