Chris Adams wrote:
>
> Frank T. Brady wrote:
> >
> > Hi all -
> >
> > I've just purchased two Rohn H50 steel telescoping antenna support masts.
> > They have 5 sections that extend to about 50 feet. I bought them to support
> > a G5RV or Double Zepp, but as I was surveying the installation area I
> > thought maybe they could serve a dual purpose as verticals for 20 and/or 40
> > meters.
> >
> ------------- snip
>
> Frank,
>
> I have considered doing what you are suggesting (i.e. verticals with
> telescoping mast although even suspending horizontal antennas wouldn't
> be a bad idea either) but have never gotten around to it.
>
> That said, there's an article in the May 1994 issue of QST by Bob
> Haviland, W4MB on the ability to use a telescoping mast to support ham
> type beam antennas. That said, he makes a passing mention of using the
> mast as a vertical....
>
> "The TV mast itself can be used as a vertical antenna with no
> additions. Add a set of three to six wires parallel to the mast, and up
> to a foot or so from it, to form a cage for low loss and improved
> bandwidth. A bottom insulator of fiberglass cloth and resin can be
> used, or the wires can be fed as a folded dipole. A 3, 5 or even 10
> foot capacity-hat is within the design capability of these masts (he
> means they will stay standing). The usual rules about good grounds
> apply."
>
> Another good reference is the artical "Vertical Antennas: New design
> and construction Data" by Doty-K8FCU, Frey-W3ESU (K4VX now??) and Mills,
> K4HU. This artical can be found in the ARRL Antenna Compendium, Volume
> 2. It mentions the folded monopole which is what I "think" Havliland is
> actually referring to.
>
> chris, n4vi
>
> --
> 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
Frank ... I have forwarded your message to Dave Hockaday WB4IUY, we have
been working with the Rabbits getting them ready to use... You can visit
his web page to see some of our work at
http://www.ipass.net/~wb4iuy
We are setting them up as time permits ... do you have a source for more
of the 900 mHZ Rabbits???
Dave should respond in a day or so ... he's real busy right now at work.
They will tune the ATV band and with a few mods will be very stable and
there are brick amps (not too expensive) to add to them.
Later .....
Steve
KD4WIW
--
===========================================
E-mail: kd4wiw@ipass.net
Home Page: http://www.ipass.net/~kd4wiw
Packet: KD4WIW@W4RAL.#RTP.NC.USA.NOAM
===========================================
TOWERS ARE BEAUTIFUL !!!!
===========================================
--
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
|