The Rohn 45G brochure shows a round base 2'6" in diameter, 4 feet in the
ground,
with 6" above ground, with pier pin for towers up to 150' at 110mph wind.
Same
base is OK for up to 200' at lower wind speed. The base has 8 #7 vertical
rebar
in a circle plus some #4 rebar rings (1 cu yd of concrete). This all depends
on soil
conditions, local codes, etc of course.
The brochure also says one could make a square base 2'6" on a side. No
mention
of using the short base in concrete and how it might affect the rebar
schedule.
I have a square base on my 100 foot 45G with concrete ending slightly above
the
bottom of the legs in gravel on a short base. It has made it through a
couple of hurricanes
and a tornado so far without problems.
73, Larry W6NWS
----- Original Message -----
From: "Stan Stockton" <stan@aqity.com>
To: <towertalk@contesting.com>; <starrose444@aol.com>
Sent: Thursday, September 15, 2011 9:08 AM
Subject: Re: [TowerTalk] 45g Tower
> Bob,
>
> All this is just opinion:
>
> I suggest that you consider putting up one tower and making it about 85
> feet tall. There would be four fewer holes to dig, fill with anchors,
> concrete, etc. You would only need two sets of guy wires (same as what
> you were planning except all on one tower) and whatever you will put up
> will be overall better at that height than at 35 feet. You would have
> the option of antennas at lower heights either fixed in one direction or
> rotating with a side arm.
>
> Unless you are on top of a hill with a steep drop off near the tower,
> where an antenna may actually work better at 40 feet than at 80 feet,
> the elevation above sea level makes little difference except for its
> relation to surrounding area and line of sight communications. In other
> words someone on a little 100 foot hill surrounded by sea level is in a
> much better location than someone on flat land for miles in every
> direction at 2000 feet elevation.
>
> As far as the base is concerned I think 5 feet deep is way overkill.
> For a guyed tower, all you are trying to do is keep the thing from
> sinking. Check the source who said 5 feet is needed and see what they
> say about 3 feet versus 5 feet.
>
> Stan, K5GO
>
>
> ----- Original Message -----
> From: <starrose444@aol.com>
> To: <towertalk@contesting.com>
> Sent: Wednesday, September 14, 2011 6:05 PM
> Subject: [TowerTalk] 45g Tower
>
>
>>
>> Again thanks for all the information about using a mid section for a
>> base.This is my first tower so I want to do it right.I have 8 10ft 45g
>> sections and one 45ag top section would like to make two towers.Each
>> tower will only be about 35-45 feet in height I am elevated at 1100
>> feet now on a very large farm.I was told the hole should be about 3x3
>> and 5 feet deep.They will not be aginst the house so I have two sets
>> of guy wires Iam thinking a set on each?Any information like how much
>> gravel in the hole grounding etc.
>>
>>
>>
>>
>>
>> Thanks
>> Bob
>> Kc8phb
>> _______________________________________________
>>
>>
>>
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>
> _______________________________________________
>
>
>
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