I've done a lot of experimenting trying to find the perfect
"portable" RX antenna. First let me mention that I use
T posts with plastic pipe slipped over them to hold up
my open wire line, at a height of 5 feet. In the rainy
season, the ground softens up and during storms, the
posts lean over maybe 20 degrees and take a permanent set
in the direction of the prevailing wind. I have tried
them with vertical antennas, but the whole antenna blows
down.
If you study the physics of a 30 foot high 2 inch diameter
tube in a 50 MPH wind, it becomes apparent that there is
no portable solution that is going to work. I thought I
could make a cross out of 2x4 lumber and put weights at
the end of the arms of the cross. The amount of weight
required is prohibitive if you want portability.
Instead, I have reluctantly concluded that I must guy
all "portable" masts. I pound in T posts for guy attachment
points. I have tried simpler guy points, but they have
pulled out in storms.
I think the only portable antenna that will really work is
the 102 inch CB whip. Not much wind area and anyway, it
bends in the wind.
Rick N6RK
Mr Magoo wrote:
> Regarding W5ZN's post about making an RX antenna "portable" using a
mast supported in a bucket of cement: I tried that trick a few years ago
when I used to string Beverages out across my neighbour's field. I
poured cement in 20 gallon paint pails with a 10 ft mast....pretty heavy
to move but I got them in place with the aid of my tractor. First
strong wind storm took the whole lot of them down and I had to guy each
one to keep it in place. It was a lot easier to drive in a T post and
place a length of plastic pipe over top.
>
> I think that any antenna installed this way in cement would have to
be very light (fiberglass poles) and not too long (less than 20 ft) to
prevent tipping in strong winds.
>
> Bill VE3NH
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
>
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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