Answer 1: Likely so, although with a half sloper the tower and
everything connected to it becomes part of a complex radiating system so
it's pretty much a crap shoot what the interactions are.
Answer 2: Very difficult to say. See Answer #1 above.
Answer 3. Possibly. If the tower is short enough not to be close to
resonant, you might end up with a merely short Inverted-L with less
destructive interaction.
Suggestion 1: Why not shunt feed your 90' tower? I'd bet it would
knock the socks off any sloper or Inverted-L hung from that same tower,
and it isn't any more difficult to build.
73,
Dave AB7E
rlvz@aol.com wrote:
> Hi Guys-
>
> I'd appreciate your recommendations on building a Half Sloper for 160-m.
> I realize that some folk have had excellent results with Half Slopers and
> 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 to
> keep the minimum angle between wires at 90 degrees or greater. Since Half
> Slopers almost never have a 90 degree angle between the sloper wire and the
> tower is this one reason why many Half Slopers don't work very well... lots
> of signal cancellation?
>
> Question 2: I have a 90' tower with a Tribander on top which makes it very
> 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 to
> heavy coupling between the Inverted L and the tower. (some models say that
> alot of RF is shorted right to ground!) Therefore, I am thinking of going
> with a Half Sloper connected near the top of the 90' tower with the sloper
> wire running NE towards Europe. If I anchor the end of the sloper wire
> about
> 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 coupled
> 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 Europe...
> keeping in mind that this is a temporary antenna so I can only put down a
> 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 is
> fine! Please let me know which of the above options you believe is most
> likely to provide the best 160-m. signal towards Europe.
>
> Happy New Year!
>
> 73,
> Dick- K9OM
> Edgewater, Florida
>
> _______________________________________________
>
>
>
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>
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