"John Smith" wrote in message
...
Idea 1, would probably not work much at 446 as current would have a hard
time to flow into attached insulated wire. general problem with most
mobile
antennas is getting enough RF current to flow out into them.
There are two ways that Idea 1 can be thought of:
A. The extra wire is a half wave dipole coupled to the 2 meter quarter
wave. By some magic, it resonates and radiates on 446 MHz as a half wave
dipole.
B. A shorted quarter wave transmission line is an open circuit. So is a
half wave open circuit transmission line. The extra wire next to the 2
meter quarter wave acts like an open half wave transmission line,
effectively isolating the upper part of the 2 meter quarter wave when
operating on 446. When the wire is positioned properly, the bottom part of
the 2 meter quarter wave will act like a 446 quarter wave.
Jim
N8EE
to email directly, send to my call sign at arrl dot net
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