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Old July 19th 05, 08:39 PM
Richard Harrison
 
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Jim Kelley wrote:
"You take too great a liberty with the name Eugene Hecht. Among the
things which won`t be found in any of Dr. Hecht`s texts is a minus sign
in front of a number expressing an impedance."

Don`t know why not. It happens at radio frequencies all the time. Look
through Kraus` chapter on "Mutual Impedance of Other Configurations".

B. Whitfield Griffith, Jr. gives a practical example starting on page
427 of "Radio-Electronic Transmission Fundamentals". On page 429 he
writes:
"We immediately notice one disturbing fact: the resistance component of
tower 1 has come out to be a negative number. This does not mean the
computations are wrong; it simply means that this tower because of the
particular phasing and current relationships of this array, will be
absorbing more power than it will be radiating itself."

This is an old story with broadcast antenna arrays.

Best regards, Richard Harrison, KB5WZI