I like my 40' tilt-up rotatable mast, easily made from
inexpensive 1-1/4" Schedule 40 steel pipe + various
fittings. Some simple welding is required. Using a
falling derrick, one person can easily & safely tilt
it up/down. A few bodies make it go faster. I've
used it several times since the early 1990s.
An 80m cage inverted vee and a 40m inverted vee
form the top guys. BW on 80m is almost 400 KHz, and
we tune it for 3500 to 3900 KHz. With a tribander
on top, it covers 80-40-20-15-10m.
Rob, see my links to drawings, detailed construction
info, photos, and a video clip (sent privately).
vy 73,
Bryan WA7PRC
> Date: Tue, 4 Jun 2013 18:47:57 -0700
> From: Dick W1KSZ
>
> I remember seeing a ladder used as the support. Probably
> easier to
> walk up than a single mast.
>
> 73, Dick, W1KSZ
>
>
> On Tue, Jun 4, 2013 at 6:09 PM, K8RI wrote:
>
> > On 6/4/2013 8:19 PM, Robert Fanfant wrote:
> >
> >> Our field day team is planning to put up a SteppIR
> 2 element yagi (~25
> >> pounds). We'd like to mount the yagi ~20-30
> feet high and would like mast
> >> recommendations. This is only a field day
> (i.e. once a year) event so cost
> >> is a factor, yet the mast should be strong enough
> so that we aren't out the
> >> price of a replacement antenna. Our field day
> location will be in eastern
> >> WA where we at times tend to get moderate winds
> (~10-20mph) coming through
> >> our campsite. Thoughts?
> >>
> >>
> > Can this be one piece, or does it have to be in
> sections?
> > If you have a nearby metal supplier, you can purchase
> tubing, either
> > structural steel or pipe. Structural Tubing comes
> in schedule 40 and 80
> > just like pipe and is rolled with a welded seam
> >
> > I purchase the tubing in steel and Aluminum. The
> Aluminum is drawn and
> > seamless. It comes in a variety of alloys and wall
> thickness. For what you
> > want 1/8th inch wall should suffice in 6061-T6.
> There are stronger alloys
> > if you wish and I purchase 1/8th, 3/16ths, and 1/4"
> wall. The only
> > drawback to this is, standard sizes do not easily
> telescope. The steel is
> > also available as DOM. However as cost is an
> issue, we can pretty well
> > rule out DOM.
> >
> > All are sold by the pound.
> >
> > It's been quite a while since I purchased a load og
> steel and aluminum so
> > I don't remember the prices which would be out of date
> anyway.
> >
> > -Rob N7QT
>
>
> Date: Tue, 04 Jun 2013 20:54:20 -0700
> From: Jim Lux
>
> A couple lengths of pipe with a coupler or lots of duct tape
> might work.
> Armstrong rotator?
>
>
> A 30 foot extension ladder (you can rent them pretty cheap)
> is another
> good way. You can lash a rotator to it, it walks up pretty
> easily as
> long as you have 3 or 4 people, and guy it with ropes and
> stakes.
>
> Check your local rental yard.. they have all kinds of stuff
> that might
> work out real well for you.
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