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Old September 2nd 10, 09:49 AM posted to rec.radio.shortwave
RHF RHF is offline
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First recorded activity by RadioBanter: Jun 2006
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Default What is the Best Direction to 'Point' a Sloper Antenna for DX ?

On Aug 31, 7:11*am, dave wrote:
RHF wrote:
What is the Best Direction to 'Point' a Sloper Antenna for DX ?


Given an area where you could locate a Sloper Antenna
with a Tall Mounting Pole "Top-End-Feed-Point' and the
ability to move the Bottom-Far-End around the full circle
of 360 Degrees.


Where would you place 'Point' the Bottom-Far-End for the
best DXing ? [ N ? E ? W ? S ? ]& *WHY ?


- Top-fed slopers in an open space are essentially
- omnidirectional.

OK but most are 'in' close-in space with all sorts
of things around them.

-*Most of the radiation happens at the feed point.

Yes there is more power radiating around the feed-point.
-but- I a talking about a SWL Receiving Antenna.

- The slantwire and the support structure form a
- low Q mass that also radiates, equally well in
- all directions.

Not 'If' the Support Structure is a Grounded Metal
Tower/Mast.

Many of the Commercial Slopers use an attached
Counterpoise Insulated Wire to hang-down to the
ground along the Side of a Building to act as the
Grounded Tower/Mast {Reflector} to give the Sloper
some directivity and to better 'Match' the Antenna
to the Feed-in-Line.
http://www.universal-radio.com/catalog/sw_ant/0013.jpg
http://www.alphadeltacom.com/images/dxswl.gif
http://t2k.wdfiles.com/local--files/...sloper-002.jpg

"A Sloper which is at an angle they will be more
directional the direction that they are sloped."
http://www.angelfire.com/mb/amandx/dipole.html

Full 1/2 Wave Sloper Antenna : The radiation
pattern will be almost omnidirectional ... with
a slight advantage toward the "sloping" direction.
http://www.hamradiosecrets.com/ham-r...f-antenna.html

Half 1/4 Wave Sloper Antenna : Omni-Directional
pattern, but with some "warping" in the direction
of the wire slope.
http://mysite.ncnetwork.net/resvzazs/80endfed.htm

1/4 Wave Sloper : It does appear to offer gain
in the direction of the sloping element.
http://home.centurytel.net/WD0M/antennas1.html

Some of this may be the fact that these Slopers
are Mounted to Metal Towers/Masts and the
Grounded Tower/Mast may be acting like a back
Reflector and causing some of the Radiated
Directivity from the Tower to the Sloping Wire
and out away from them.