Dr. Slick wrote:
"---creating antennas to most efficiently transfer power to free space
is a similar problem to matching a circuit`s source to its load. (Quote
from Shadowitz)"
Reciprocity rules in antennas. Kraus has an Apendix D (Absorbing
Materials) to his "Antennas For All Applications".
Kraus says:
"The use of space cloth (Z=377 ohms per square) placed lambda/4 from a
reflecting plane was invented by Winfield Salisbury (1) at Harvard Radio
Research Laboratory during WW-2 ---." (Shades of stealth)
However, a century of antenna experimentation has not revealed a
practical need to especially design an antenna to match its radiation to
a resistive 377 ohms.
Most effective radiation occurs when the antenna circuit is matched and
has no loss. 100% of the energy accepted is radiated.
Best regards, Richard Harrison, KB5WZI
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