My attention has recently been drawn to the concept of the Cross Field
Anntena. Which if it works might be the solution to problems of power and
sixe. I quote the attached snipit from the antennex web site.
"Let me tell you about one example, lest you think this is all for naught: A
CFA only 21 feet (6.5 Meters) tall, located at Tanta in the center of Egypt,
provides AM broadcast service at 1.16 MHz (258 Meters) to millions of people
from Cairo north to the coast. Certified measurements provide evidence that
this small CFA produces a radiated signal almost 6 dB stronger than the
previous 1/4 wavelength vertical broadcast tower which was 211 feet (65
Meters) tall. To express the performance a different way >> with the tall
tower, a 100,000 watt transmitter was required for the desired coverage.
With the miniature CFA the same coverage was attained with the transmitter
power reduced to 30,000 watts."
The following site will be of interest.
http://www.luminet.net/~wenonah/cfa/
http://www.antennex.com/preview/cfa/cfa.htm
http://www.radioworld.com/reference-room/Cross-Field-Antenna/2000/rw-rackley
1-doc.html
http://www.wbeonline.com/html/2000/Oct.news/crossfield_10_23_00.htm
Martin M5CIX
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