[TowerTalk] Re: Slopers, half slopers, (using the tower)

Tom Rauch w8ji at contesting.com
Wed Dec 29 19:41:13 EST 2004

> In my case one leg can be a 55 foot Rohn 25 tower, at 55
> I can directly/electrically attach a horizontal wire out
> 80 feet to the feedpoint then another 135 feet to the far
> insulated by a tie rope up in a tree.

I'm a little confused by that description.

> 100+ feet of the horizontal section will go across a
> ravine thereby increasing the effective height at the
> feedpoint.
> Fed with open wire I am guessing this will be a decent
> NVIS doublet/dipole antenna on 160 and 80 and an
> antenna for 40-10M.

It sounds like you are planning on using the tower (55ft)
plus a wire length (80ft) then feed with balanced line and
continue out another 135ft with a floating wire. That isn't
a half wave antenna Doc, and it certainly isn't balanced.
The tower is not only a much larger diameter, it is also
grounded. It also has "stuff" on it.

I'm not saying that it won't radiate, but I don't think
anyone would know how well or how poorly it would work short
of trying it. That system could radiate mostly vertical,
mostly horizontal, or mostly just dissipate applied power in
loss resistances (mostly ground losses).

I think you'd be better off just using an Inverted V dipole
or regular dipole if you want an NVIS antenna.

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