In a message dated 98-03-20 11:13:38 EST, larsenp@cadvision.com writes:
<< whereas the ARRL Antenna Book states
> that the
> specifications on both F/B and gain are slightly better with a
> combination of
> driven element and director? >>
The DE-DIR combinations have more gain due to being tightly coupled and
therefore the input impedence is quite low... (Read Moxons analysis of
supergain antennas) Very low impedence antennas tend to have excessive losses
and thus the beam overall has less gain than one with a more modest degree of
coupling and a higher impedence....
Denny
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