Have you looked at the pattern of a 40M dipole on 20, 15, 10?
On 20M it is 2 half waves in phase which gives a figure 8 pattern
broadside to the wire with a beamwidth of around 50 degrees. Feed
impedance is several thousand ohms at resonance.
On 15M it is a current fed 3/2 WL Long Wire with the main lobes
about 30-35 degrees from the wire and a lesser and much more
narrow lobe (~10 degrees) broadside to the wire.
On 10M it is 2 Full Wave Length Long Wires in phase with 4 lobes
centered around 30 degrees from the wire and a deep NULL broadside
to the wire.
These patterns ASSUME the dipole is HORIZONTAL, not an inverted vee.
Not exactly the 4 band wonder to cover the SOUTH you are looking for.
Have you considered a nice trap dipole that you could mount on a
tower leg and would give you a figure 8 pattern on all 4 bands?
Check out the Cushcraft D4.
Tom N4KG
On Mon, 20 Aug 2001 GALE STEWARD <k3nd@yahoo.com> writes:
>
> Have been thinking of installing a simple antenna to
> cover the SE in contests and as a backup in general.
> Was considering a inverted vee hung from the tower and
> fed with ladder line & tuner. I want to cover only 10
> thru 40. My question is this: my tower is about 100
> ft ftom the house and want to feed this antenna with
> ladder line near the ground, how do I handle that
> transition to coax? A 4:1 balun, a 9:1 balun, other?
> Is it even worth doing with the losses incurred due to
> the mismatch in 100 ft of coax? Maybe a trap dipole
> or inverted vee would be more appropriate? I just
> wondered if anyone had tried something similiar and
> how it all worked out.
>
> 73, Stew K3ND
>
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