I agree with Joe, sounds like you need some expert engineering from a local
ham club. Better to be safe than sorry (killed).
73,
Bob, K3GT
>
>Hi Dave, de Joe AA4NN
>Please get in touch with a local Ham Radio Club, people who know
>about erecting towers in your locality. You'll meet new friends and
>find yourself with better advice on what you are faced with.
>73, de Joe AA4NN, aa4nn@juno.com
>
>On Fri, 8 Oct 1999 11:46:57 -0700 "Dave H." <wiseguy@attitude.com>
>writes:
>>
>> Hi to All,
>>
>>
>> I am a new member to this fine forum of information "Tower Talk".
>>
>> I have just purchased a 80' crank up Tower . Dont know the
>> manufacture .
>> This tower is extremely heavy (two guys can barely lift it off the
>> ground)
>> it's galvanized and is in 20' telescopic lengths.it is made of 1"
>> tubing,
>> the largest section is 14" x 14" x 14" (a triangular design) (inside
>> ones
>> are smaller than the next 4 total= 80') The tower has "ears" at the
>> top of
>> each section or tabs to connect guy wires to them. The tower is a
>> ladder
>> design and cross bars are horizontal (ladder type) not Chris-cross
>> . A bar
>> design,(as opposed to a (X) design.) I hear this is not strong like
>> the X
>> design.
>> It can be laid over on two bolts/pins, tilt up into place and then
>> one
>> would add the third pin to the base plate.
>> these bolts don't seem strong enough to do much of anything other
>> than to
>> keep it into place on the 3/4' steel base plate which has 4 large
>> holes at
>> the corners for the base bolts (1" I think) the use of 2' long "J"
>> bolts
>> might work well here.
>> I was thinking of a 3x3x3 base pour 4" above grade, since the tower
>> is not
>> of the "free standing" variety.
>> But, I live where the soil is considerably heavy,(California
>> Desert) when
>> the soil is saturated it becomes terrible, and in the summer months
>> it is so
>> hard I have to drive a spike with a large hammer in the ground just
>> to put a
>> sprinkler in place (the type with a 7' spike on 'em)
>>
>> As far as placement on the property goes, I have enough property to
>> locate
>> it anywhere. So, the $64K question is...do you guys think it should
>> be AWAY
>> from the house? or, NEXT to the house? if we go next to the house,
>> one set
>> of the the guys will be in the front yard. Since I have more than
>> ample room
>> on this property for the tower and guying. If I set the tower away
>> from the
>> house how far should this be? and do I run the cables down a nearby
>> guy wire
>> or underground from base.?
>>
>> I am guying it 3 ways (120 degrees apart).
>> One of my main concerns is the degree of guying the antenna down. I
>> want to
>> get away with going with 30 degrees. Should it be guyed at each 20'
>> section
>> or one near the top and one set at the second section? which is @
>> 40'. I am
>> going to be running 10 meters, I have a 8 element beam by Avanti
>> (AV-140)
>> some know it as a "Moonraker IV". (dimensions are 19' boom, from top
>> to
>> bottom each element is 20' has horiz. and vert. elements) this
>> antenna has a
>> wind load of only 5 sq.. ft. and weighs 24 pounds so with this
>> factor, I
>> want this thing to last through "super cell storms" with no
>> problem.
>> eventhough I live in a mild climate.
>> I would like to guy with "poles" so one can walk around the pole
>> rather than
>> trip over ground level turnbuckles. Any comments?
>> The prevailing winds are from the NW and there can be gusts of what
>> I've
>> seen in the past 11 years here of about 40 mph. So, would pointing
>> or guying
>> a tower directly into the prevailing winds benefit the load better
>> or should
>> I consider the placement of the guy wires first and formost in the
>> landscape? what about running two guys off same eyelet at 60 degrees
>> into
>> the prevailing wind? or does this matter at all.?
>> Also the issue of running a solid run of guy wires, is it truly
>> necessary to
>> break these up with insulators? I heard 22' to be the rule. I would
>> think
>> just run the guys solid all the way to the tower.
>> I think the solid run of a guy is important and that I shouldn't
>> worry
>> about breaking them up for ''coupling or resonance" issues. I just
>> was
>> worried about the vertical elements getting too close to the top
>> guys and
>> that they are metal because, The worst part is at the top. this
>> antenna has
>> 9' vertical elements from the boom. if I guy at the top eyelet, the
>> tower
>> won't rotate. Is this solved by guying at 10' lower point on tower,
>> or using
>> a 10' section of mast putting antenna well above top plate? or how
>> is it
>> going to turn a vertical beam?
>>
>> I'll need to look into the anchors as well. What do you think about
>> having
>> them at ground level with big turnbuckles on them. OR getting a
>> large
>> diameter. pole as to be able to walk around the guys since they
>> terminate
>> 5-6' on to of the pole?Whatever type I decide on they will be
>> cemented in.
>> so I need to know what dimensions of a base pour these "anchors"
>> should be.
>> and about these "anchors" are the holes wide? or just deep?
>> Guy wire cable size is of importance I think. should I look at 1/4 "
>> ? or is
>> that an over kill?
>>
>> . I need info on base pour dimensions, grounding, guy wire distance
>> from
>> tower, type of anchors/posts for guys, insulators on guys set for
>> 10-11
>> meters,(resonance/reflector issues) ANY and all suggestions will be
>> appreciated, as I am just starting out. If you know of web sites or
>> reading
>> material for this, please help,
>>
>> As I will need to climb the tower (at lowest setting) to add the
>> antenna, or
>> will have to hire a truck.
>>
>> Thank you all for any feedback concerning this achievement, For the
>> "hoisting" of this construction , I will offer folks around here "
>> an
>> erection party". hehe
>>
>> 73s
>> Dave H.
>>
>>
>> --
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>>
>
>Vy 73, de Joe AA4NN
>Eastern Top Band ARC, Carolina DX Assn, Carolina CW Ops,
>Fairfield County Contesters, Ten-Tec only, CW only.
>eeetet ee
>
>--
>FAQ on WWW: http://www.contesting.com/towertalkfaq.html
>Submissions: towertalk@contesting.com
>Administrative requests: towertalk-REQUEST@contesting.com
>Problems: owner-towertalk@contesting.com
>Search: http://www.contesting.com/km9p/search.htm
>
>
--
FAQ on WWW: http://www.contesting.com/towertalkfaq.html
Submissions: towertalk@contesting.com
Administrative requests: towertalk-REQUEST@contesting.com
Problems: owner-towertalk@contesting.com
Search: http://www.contesting.com/km9p/search.htm
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