For One and All,

The Long and Thin Vertical Loop Antenna.
[ The Non-Resonance Vertical with a Difference ]
http://groups.yahoo.com/group/Shortw...a/message/7158

Another form of "Receive Only" Vertical Antenna for
the Shortwave Listener (SWL) is the Long and Thin
Loop Antenna. Actually this Antenna is usually
Rigged to a low Tree Limb and is often only about
16 to 32 Feet High. But since the Wire Antenna
Element is Folded (Bent) the amount of Wire in the
Air is twice as much 32 to 64 Feet. This generally
Results in an 1/ WL Vertical Antenna that is usable
in the 41M to 19M Bands and is effectively a Half
Wave Loop Antenna for those same Shortwave Bands.

Why the Shortwave Listener (SWL) may choose this Antenna :
Think of this Antenna as a Random Wire {Available Space}
Antenna that just happens to be a Long and Thin Vertical Loop
Antenna that meets your requirements for a small ground foot
print (little land area) and you happen to have a Tree to
Hang-It-From ) The Long and Thin Vertical Loop Antenna
also happens to be a fairly Stealthy Antenna when Rigged
within a few Feet of the Tree Trunk )


HOW TO BUILD THE LONG AND THIN
VERICAL LOOP ANTENNA :

Take two pieces of PVC Pipe about One Foot Long
with End-Caps on both ends.

Next take your Antenna Wire and Fold it in Two.

At the Fold (Bend) attach the Antenna Wire to one
of the pieces of PVC Pipe with the Wire separated
Wrap the Wire and Secured the Wire at each end of
the Pipe.

Attach a Long Rigging Rope (Nylon / Poly Rope)
to the piece of Pipe.

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Note - This is your "Top-Bar" of the
Long and Thin Vertical Loop Antenna.


Slowly Pre-Position {Rig} the Top-Bar part of the
way 'up' the Tree keeping the Antenna Wires Straight
and Kink-Free.

Now take the two ends of the Antenna Wire and
attach the Antenna Wire to the other piece of PVC
Pipe with the two Wires separated.

Wrap one Wire and Secured the Wire at one end
of the Pipe leaving about two feet as a free (lose)
as a tag-end.

Wrap the other Wire and Secured that Wire at the
other end of the Pipe leaving about two feet as a
free (lose) as a tag-end.

Attach a very Short Rigging Rope (Nylon / Poly Rope)
to the piece of Pipe.

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x x

Note - This is your "Bottom-Bar" of the
Long and Thin Vertical Loop Antenna.

The Feed-in-Line Connection.
Connect the Two Wire Ends to the Coax Cable :
One to the Center Conductor and the other to the
Outer Shield.

Matching Transformer.
For the Shortwave Listener (SWL) the better Bottom-Bar
Connection is to use a Matching Transformer (Balun)
with a 4:1 Ratio between the Wire Antenna Element
and the Coax Cable Feed-in-Line.

Grounding.
"If" directly connected to the Coax Cable : Then the
use a Snap-On Ferrite Core at each end of the Coax
Cable. A Ground Rod at the base of the Vertical Loop
Antenna is not recommended and the Shack's Ground
is the System Ground.
However, "If" a Matching Transformer is used then a
Ground Rod at the base of the Vertical Loop Antenna
is recommended; with the Outer Shield of the Coax
Cable attached directly to the Ground Rod.

Summary.
Looking for a very small area limited space antenna ?
The consider the Long and Thin Vertical Loop Antenna !


hope this helps - iane ~ RHF