On Tue, Nov 15, 2011 at 9:55 AM, Bill Wichers <billw@waveform.net> wrote:
> I've never personally tried a balloon or kite, but I would suspect with
> either elevated radials might be a problem due to the extra weight. You
> could, I suppose, use a few mast sections to hold up the elevated
> radials in the center and then run your aerial wire from the top of the
> mast to the balloon/kite to keep that weight off the skyhook though.
>
That was one thought I had as well, if I could get enough lift to
essentially secure the feedpoint via the radials and pull the entire mess
up. It would be something to behold but I'm not sure of its likelihood of
success. I know there are some pretty capable lifting kites, but it would
sure make an already delicate change of success even more tough.
Experiments are needed for sure, the kids are all fans of kites, I can
probably get approval for such activities from them.
>
> What I *have* done is to use the surplus military masts -- the aluminum
> ones, not the fiberglass kind -- with a surplus insulator at the bottom.
> Depending on the type of mast kit you use, you should be able to get up
> to 30-44 feet or so with the smaller mast kits. These are fairly strong,
> although they require guying, and they can easily support a reasonably
> large top hat. The aluminum mast kits generally have conductive coupling
> (i.e. the coupling parts aren't painted), so you end up with a vertical
> aluminum pipe that makes a pretty reasonable antenna. For radials you'd
> just lay out wire the same as you would for any "regular" antenna.
> Everything can pack into a duffle bag when you're not using it -- the
> mast kits usually break down into 3-4 foot long sections.
>
>
Dad has some aluminum sections he says were to clean artillery maybe, he
has enough for a 40M vertical but I don't know where they are anymore. I
had that similar thought too using mast sections, elevate the feedpoint on
a fixed structure and then come off that with wire.
> If you want to use the cheaper fiberglass mast sections make sure you
> get the reinforced kind (the kind with an extra ring around the "socket"
> end of each mast section). You could then suspend a piece of heavy wire
> inside the mast and use that as the antenna element. I haven't tried the
> fiberglass sections myself except as a K9AY center support, but I don't
> see any reason they wouldn't work to hold up a vertical wire and top
> hat.
>
> If you do use the mast kits to hold up a top hat, it would be helpful to
> have a helper to get the mast in the air. The masts tend to want to
> buckle in the middle as you raise them so it helps to have one person
> "walk up" the mast while another pulls up the guy lines until the mast
> is vertical. Once it's vertical you need to set the guys, but using 4
> guys instead of three you can "pre-set" three of the sets to the correct
> length so that only the fourth set needs to be snapped onto a ground
> stake to complete the installation. The completed mast can take some
> pretty strong winds with no problem so would have a pretty sturdy
> temporary installation that wouldn't be affected by too strong or too
> weak winds.
>
I think a top hat may be too ambitious, I'm likely on my own when the time
comes, or at least the only adult.
Thanks, good stuff.
Chris
>
>
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