[TowerTalk] Half sloper recommedations needed

Doug Renwick ve5ra at sasktel.net
Fri Jan 1 09:52:46 PST 2010


I have successfully used full size half slopers on 160m for years.  On
my 110 ft tower the half slopers are anchored at the 100 ft level and
they come off the tower at about a 45 degree angle and they droop.
Above the tower top are stacked forty and ten meter beams.  I also have
a few full size radials lying on the ground and tied to the grounded
tower base at ground level.  IMO you can model this all you want but you
won't really know how well or poorly it works until you install and test
it.  Now to do some bragging at my northerly mid west location (some
call it a black hole) here in Saskatchewan.  I have just gone over the
200 country/entity level which I believe is the first for any Canadian
station west of VE3.  Of course a good receiving setup is a big help
also.  You can also check the cluster for the many EU spots for VA5DX
this past outstanding year.


-----Original Message-----
From: towertalk-bounces at contesting.com
[mailto:towertalk-bounces at contesting.com] On Behalf Of rlvz at aol.com
Sent: December 31, 2009 3:28 PM
To: towertalk at contesting.com
Subject: [TowerTalk] Half sloper recommendations needed

Hi Guys-
I'd appreciate your recommendations on building a Half Sloper for
I realize that some folk have had excellent results with Half  Slopers
others have had terrible results with them!  That's why I'm  asking for 
advise on how to construct my Half Sloper!
Question 1: Most antenna articles say when constructing an Inv. Vee is
keep the minimum angle between wires at 90 degrees or greater.  Since
Slopers almost never have a 90 degree angle between the sloper wire and
tower is this one reason why many Half Slopers don't work very well...
 of signal cancellation?
Question 2: I have a 90' tower with a Tribander on top which makes it
close to a 1/4 wave for 160-m.  I installed an Inverted L on this  tower

with 85' vertical and the Inv. L radiating efficiency is very  poor due
heavy coupling between the Inverted L and the  tower.  (some models say
alot of RF is shorted right to  ground!)  Therefore, I am thinking of
with a Half Sloper  connected near the top of the 90' tower with the
wire running  NE towards Europe.  If I anchor the end of the sloper wire
200' from  the tower the angle is only going to be about 45 degrees.  Do

you think  this will work any better towards Europe than my heavily
and inefficient  Inv. L?  (another weakness with my Inv. L is that I
have a 
minimal  radial system as it must be pulled up each Spring).
Question 3: Rather than build the Half Sloper on the 90' tower  would an

Inv. L on my 60' tower with 55' vertical and the rest horizontal
running NE 
towards Europe likely outperform the Half Sloper at 90' towards
keeping in mind that this is a temporary antenna so I can only  put down
minimal radial system as the radials need to be removed  in Spring.  
I realize that I'm likely to get a variety of opinions on this and that
fine!  Please let me know which of the above options you believe  is
likely to provide the best 160-m. signal towards Europe.
Happy New Year!
Dick- K9OM
Edgewater, Florida

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