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Re: [TowerTalk] 160-m Inverted L or Sloper?

To: <>, <>, <>
Subject: Re: [TowerTalk] 160-m Inverted L or Sloper?
From: "Tom Rauch" <>
Reply-to: Tom Rauch <>
Date: Mon, 14 Nov 2005 06:27:26 -0500
List-post: <>
> If I've understood this track, a sloper is just a way of
> the tower it is connected to, and the radiation pattern,
good or bad,
> is controlled by the tower and what's on it, and not the
sloper itself.

Not quite. The sloping wire also has substantial current. So
it does affect pattern. The tower is half of the system, and
can cancel radiation from the sloping wire, radiate more
than the sloping wire, or even just carry current to ground
where it is dissipated as heat.

Each terminal of non-radiating coax must source or sink
equal currents. So consider the feedpoint that way, as a two
terminal equal current source, with a big mess hanging on
one terminal and the sloping wire on the other.

> Does that really mean that I can move the end of my 135
foot sloper from
> its present position, to the NE, 180 degrees to where it
would be sloping
> to the SW, and expect no change in its very satisfactory
> on 80 and 160??

NO. One thing for sure is the wire radiates. What isn't
certain is what the tower does. It can cancel radiation, it
can just act like a non-radiating counterpoise, or it can
skew the pattern. It basically cannot add much gain, but it
can remove gain in some or all directions.

>  (That would put all of the sloper over my property,
instead of my having
>   to sneak the end across the street at Sundown so it was
"pointing" NE!).
> Will the direction the antennas above the feedpoint are
pointed at have
> any significant impact on the sloper-fed tower's pattern?

No one knows Barry. That is why they are sloppers. It's a
sloppy feed system that might work one way or another
totally different way. Results vary with the tower
structure, what's on the tower, guy lines, other antennas
nearby, grounding of the tower, control cables and feedlines
leaving the tower, and so on.

You can ask all the question in the world about a slopper
and the only real answer is to use the Edisonian method. If
you try enough fibers in random filament tests, eventually
you might stumble on a light bulb. Sloppers are a religious

73 Tom


See:  for "Self Supporting Towers", "Wireless Weather 
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