My experience in comparing an inverted vee to a half-sloper has been as follows:
The half sloper is a bit of a "bastard" antenna. To get 50 ohms from
it, you have to vary the angle of the sloping wire, so using guy wires
poses a bit of a problem. I also found that a half-sloper worked well
on a unguyed tower. Once I extended the tower and added guy wires, I
could not get the half sloper to work. When using a half sloper, add
radials to the base of the tower, as it acts as a vertical.
An inverted vee has a higher angle of radiation compared to the
half-sloper. You may need to adjust the angle of the inverted vee to
get a good match to a 50 ohm load. I would not recommend using guy
wires for this purpose.
I am sure there are folks who can help you with modelling this, but
the bottom line remains the same - not recommended...
Tom - VE3CX
On Mon, Apr 20, 2009 at 4:27 PM, Cal Zethmayr <w4gmh@cox.net> wrote:
> Couldn't one of the newer and higher quality coax switches be used to make it
> possible to choose from several different combinations?
>
> I'm working on plans for a 90' tower.
> Has anyone used the top set of guy wires, with johnnyball insulators at the
> correct places of course to make an inverted V, or Sloper?
>
>
> OR..maybe using the guy wires connected at 60' for another sloper or Inverted
> V?
>
> And of course using johnnyball insulators on the lower two sets of guys to
> break them up into non-resonant lengths..
>
> Ironically I was studying the K1WA sections of the antenna handbook this
> morning and contemplating sending this question out to the towertalk panel of
> experts.
>
> Cal Zethmayr
> W4GMH@cox.net
>
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