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Old June 25th 06, 08:36 AM posted to rec.radio.shortwave
RHF
 
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Default The WellBrook Active Loop Antenna ALA 100

GA,

You may wish to consider the Size and Spacing parameters
of a T2FD Antenna as a guide in determining whether as the
"Design" Frequency effects the Spacing between the Turns
as the Frequency gets Higher or Lower

* The Formulas for Calculating T2FD Dimensions are as follows.
http://www.hard-core-dx.com/nordicdx.../t2design.html

Generally the Distance between the Turns {Spacing} will
get Wider as the Frequency gets lower. - But you already
knew that )

T2FD -- The Forgotten Antenna -by- Guy Atkins
http://www.hard-core-dx.com/nordicdx...wire/t2fd.html

I would think that starting with the Sixty Feet Single Turn
WellBrook ALA100 Loop Antenna that the progression form
One to Two Turns to Three Turns . . . would require increased
spacing for each added turn to maintain a certain band width.

One-Turn with Sixty Feet Perimeter with 15 Feet
per Side of a Square/Diamond.
- - - Resulting in a Very Thin Loop Antenna that is
about 22-Feet Top-to-Bottom and Side-to-Side.

Two-Turns about Four Inch Spacing with Thirty Feet Perimeter
with 7.5 Feet per Side of a Square/Diamond.
- - - Resulting in a Three Inch Thick Loop Antenna that is
about 11-Feet Top-to-Bottom and Side-to-Side.

Three-Turns about Six Inch Spacing with Twenty Feet
Perimeter with 5 Feet per Side of a Square/Diamond.
- - - Resulting in an 12-Inch Thick Loop Antenna that is
about Seven Feet Top-to-Bottom and Side-to-Side.

Four-Turns about Eight Inch Spacing with Fifteen Feet
Perimeter with 3.75 Feet per Side of a Square/Diamond.
- - - Resulting in an 24-Inch Thick Loop Antenna that is
about 6 Feet Top-to-Bottom and Side-to-Side.

The smaller more maneuverable Loop Antenna becomes
increasingly Thinker in order to maintain the same
Band-Width for the Loop.


at least that is the way i envision them -iane ~ RHF