Thanks Buck - I appreciate your advice. The size of the antenna is large -
about 7 ft. sq. I wasn't planning to put it any higher than about 5 foot
above the second floor. It is a standard 2 story house, with a single floor
over the garage and living room. I was thinking of placing the tower
(really a beefed up mast), attached to the side of the second floor. I have
all the wind loading calculations and the loading is very nominal with a
short mast, since it is primarily an overturning moment. By limiting the
length, the moment is much smaller - hence the desire for the short mast.
Use of a tower, even one attached to the house would require extensive
permitting, etc. But, I am also going to look at that and the use of a
tubular tower like an MA-40 if I can find one at the right price.
Scott
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com]On Behalf Of Buck - N4PGW
Sent: Sunday, July 17, 2005 4:08 PM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Simple Tower Construction
Scott,
I can't visualize your antenna tower with the ladder on the roof, but if you
put anything on the roof, it needs to be fairly small. As you have read by
now, the roof isn't designed to handle towers. A small triband beam on a
tripod mount on the roof should work well. I am not familiar with the size
or windload of the antenna you referenced in your OP, but if it can be
rotated with a relatively small rotator, it should work well on the tripod
roof mount. I would discourage anything larger. I have seen what wind can
do to structures much better supported than with a roof.
I just reread your ladder idea. I don't have a perfect picture, but I think
you are dreaming. If you put up a tower, put up one that is made for your
purpose and nothing less. (That's not to say you can't engineer one for
yourself.) Consider the costs. The costs of setting it up, taking it down
and picking up the pieces if and when it happens to get blown, or otherwise,
torn down. What risk is there to you and your family if something goes
wrong and it falls from or through the roof?
I don't know how high your house is, if it is a single or multiple story.
If you place a beam on the roof, you really don't want to go more than 6-10
feet and the lower the better, unless you have additional support such as
with a chimney.
Good luck,
73
Buck
N4PGW
> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of D. Scott MacKenzie
> Sent: Sunday, July 17, 2005 3:23 PM
> To: ersmar@comcast.net; towertalk@contesting.com
> Subject: Re: [TowerTalk] Simple Tower Construction
>
> A crank up would work - but I am limited by set-backs. Having a narrow
> yard
> I would be limited to approximately 25 feet. Actually - 25 feet wouldn't
> be
> too bad - it would be better than my vertical (I think). That is why I
> wanted to put something simple on my roof.....
>
> My wife is loathe to put any holes in the roof - especially if I do it
> (she
> hides tools from me). One thing that I was thinking of, was to place a
> ladder-type support, with the mast through the center of the ladder. The
> ladder would be supported by several boards located across several of the
> 2x4 of the wood frame to help spread out the loading....or am I dreaming
> or
> delusional?
>
> KBØFHP
>
> -----Original Message-----
> From: ersmar@comcast.net [mailto:ersmar@comcast.net]
> Sent: Sunday, July 17, 2005 3:08 PM
> To: kb0fhp@comcast.net; towertalk@contesting.com
> Cc: D. Scott MacKenzie
> Subject: Re: [TowerTalk] Simple Tower Construction
>
>
> Scott:
>
> I would not recommend a tilt-over tower on the roof of your house.
> The
> average residential, framed roof system is not designed to withstand the
> forces generated by wind loading on a tower or from raising and lowering a
> tiltover, even if guyed at the roof corners. It can be done, but this
> must
> be an engineerd solution, not something we here in Cyberland can do by
> remote control for you.
>
> You could investigate a small Glen Martin tower for atop your roof.
> I
> believe some TowerTalkians have installed these and provide some advice.
> They don't go up very high, though - less than twenty feet above the roof
> from what I recall. And the taller ones must be guyed to the corners of
> the
> roof.
>
> You might also consider an alternative - a crank-up along side your
> house. A nearby (to me) ham has one such installation at his hilltop QTH;
> his backyard slopes away from his house quite quickly. He has a KT-34XL
> on
> top of his tower, plus a 2M antenna for FM voice on a sidearm bracket,
> plus
> a 2M packet antenna atop his mast. He was able to install the antennas
> initially from his rooftop. Over the years the trees have grown closer to
> his house and he now must trim the branches to be able to lower his tower.
> This is one inconvenient aspect about a tower on a small, treed suburban
> lot
> (like mine, too.)
>
> 73 de
> Gene Smar AD3F
>
>
>
> > I live in a residential area, with a limited yard (1/2 acre). Because
> of
> > the number of trees and the slope of the yard, the only real location I
> have
> > for putting up an antenna is on the top of the second floor. Any
> > suggestions? I intend on using a TH6DXX, with a 6M5X mounted above it.
> > Being an old geezer, I would love to have a tilt-over type tower
> attached
> to
> > the second floor so that I could work on the antenna.
> >
> > Thanks in advance
> > Scott aka KBØFHP
> >
> >
> > _______________________________________________
> >
> > See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather
> > Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
> questions
> > and ask for Sherman, W2FLA.
> >
> > _______________________________________________
> > TowerTalk mailing list
> > TowerTalk@contesting.com
> > http://lists.contesting.com/mailman/listinfo/towertalk
>
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
> any questions and ask for Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
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_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any
questions and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
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