The usual TV antenna type mast has guy wires (because that 1.5" thinwall
tubing just isn't all that strong). I assume though that bringing up the
enhanced safety aspect of guy wires isn't appropriate (if only because that
would imply that what they already said you could have is somehow "unsafe")
If the mast is painted appropriately, a casual observer at the street
probably couldn't tell the difference between a 1 1/2"-2" mast (TV antenna)
and a 4" mast, unless there is something else to give scale. A little bit
of diameter gives you a LOT of additional stiffness. You can also go with
a stepped approach, with a much larger diameter closer to the ground (where
nobody can see it).
As a visual experiment, you might try temporarily erecting 30 feet of 2x4
painted white (or heck, 30 feet of PVC pipe, if the day is relatively windless)
Any sort of non-loaded element for 20m is going to be on the order of 10m
long (i.e. 30 feet!) This might look a bit weird (30 foot wide antenna on
a 30 foot high pole). You're already in a compromise situation, so maybe
something with a loaded (i.e. physically short compared to half wavelength)
element might be worth looking into. At least you'll be up in the air,
which helps a whole lot, particularly with takeoff angle.
At 04:13 PM 6/19/2003 -0400, Bill Axelrod wrote:
>I finally have gotten the go-ahead from the neighborhood antenna police
>(read home owners association) to put up a mini beam on a mast at about 30
>ft or so. That's a pretty big breakthrough.
>So, before I get too deep into it, I would appreciate some advice from the
>Tower Talk community.
>One. What mini beam would you recommend and why? Hex Beam? Cushcraft
>MA5B? Force 12 C3SS, etc.? Any directivity and gain is better than my
>current wire and vertical antennas. Am interested in all bands 20 thru 10.
>Low profile and keeping the neighbors from attacking are the paramount
>considerations. They don't see lots of aluminum in the air as a thing of
>Two. A "real" tower is out of the question. They'll allow me a "TV type"
>mast as long as it and the antenna are not visible from the street. That
>limits the total height to 30 ft or so. And guy wire/ropes are pretty
>much a no go for perceived aesthetic reasons. Since a mast with antenna
>usually requires guys, this restriction adds a challenge. I do have a deck
>with a 6x6 corner support that is buried in concrete. The top is about 12
>feet up off the ground. Perhaps I could anchor a mast there with some kind
>of support and thrust bearing in lieu of guys.
>Am open to all suggestions and advice.
>I'm sure there are some good ideas out there. Thanks in advance for the
>help and (hopefully) for no flames.
>73... Bill K3WA
>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.
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