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[CQ-Contest] Tower question long

Subject: [CQ-Contest] Tower question long
From: kc5ajx@hotmail.com (Rick Bullon)
Date: Sun Mar 15 19:37:01 1998
 Hello All
  I am finally geting ready to put in the base for my first tower 
project. I have 40 ft of Rohn 25 and plan to add another 30ft to it to 
make 70ft total height. I want to be able to fold this tower over it 
came with a BPH25G base plate and a 19ft pole to surport the tower.
  I feel that the 3/8 bolts on the base plate are to small to fold this 
over safely, would the SBH25G be a better choice? or should I build a 
stronger base plate my self? I contacted Rohn with this question and the 
response I got was "We just build them we don't energineer them" inother 
words they won't say.
  My next question is about the support pole to hold the tower when I 
fold it over. THe pole I got with the tower is 19 ft long and about 1 
1/2" in diameter. I plan to put 2 section of pipe under this the bottom 
section will be 3 1/2" in diameter and 5 ft in concrete the middle 
setion will be 2 7/8" diameter. I plan to overlap them about 6" to a 
foot so the total pole will be 5 ft in concrete and 35ft above ground 
will this be big enough pipe and be long enough to fold over the 70 ft 
tower with a TH6 on top or do I need to go higher or bigger with the 
pipe? It will only have a load on it when I have to fold the tower over.
  I've been told by a local ham that this "should work" but it would be 
best to guy the pole when I fold the tower over, so I plan to have 5 guy 
post to guy too, 3 for the tower and 2 for the pole.
It should look like this



       o                             o

           

       o             0<|              
  

       o                             o

    Well I'm no artist on the key board but in the above diagram the top 
and bottom post on the left side are for the pole when I have to fold 
over the tower over the rest are for the tower it is not drawn to scale 
but I will use the recommended 80% of the tower heigth. I beleive it 
will be 56ft out from the tower. I plan to guy this thing at 20 40 and 
60 ft ie every other section right or wrong? Can I use the drycron rope 
for guys? I hate to try and figure out where to break up the wire guys 
with insulaters and the Kelvar seems expensive but I could probably save 
up enough to get the Kelvar stuff I think the brand name is Phillystran 
isn't it?
  THe base wil be 4X4X5 ft deep is that big enough?
 Right now I have the 40ft of Rhonn 25 tower (will add 30ft more) the 
TH6 beam and a Tailtwister rotor. future plans might include an A3WS for 
the WARC bands not sure if I will try to put a forty meter beam on it 
probably will be too much antenna on one tower.
  AS you csn see I have been planing this for a LONG time, several years 
in factand I still have lots of questions. I need suggestions from the 
wisdom of the group as I don't plan having to redo this project. I want 
to do it right the first time.
  And for Steve ( sorry I can remeber your call if you want to figure 
the wind for this area I'm in Parker county Texas).
73 and Thanks
Rick
KC5AJX

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