Topband: Twin Lead Marconi Antenna
Jim Brown
jim at audiosystemsgroup.com
Mon Jun 15 09:42:39 PDT 2009
On Sat, 13 Jun 2009 22:10:08 -0400 (EDT), k8gg at voyager.net wrote:
>The problem with a 180 foot long inverted-L antenna is that over
>half of the wire is horizontal so the majority of the radiation
>is nearly vertical.
I disagree. Radiation is the result of CURRENT. Your analysis
assumes that current is evenly distributed along the wire. It is
not! The high current parts of the antenna are still vertical.
The additional length simply varies the impedance of the antenna
at the feedpoint. Yes, there will be some radiation from the
horizontal part, and the greater length will vary the vertical
pattern. And, as Herb has observed, the greater length will
increase radiation resistance, which in turn reduces ground
losses.
73,
Jim Brown K9YC
More information about the Topband
mailing list