Sender: <marv@lancaironline.net> (Marvin Kaye)
To: lml
Date: Sun, 24 Aug 2003 11:58:58 -0400
Message-ID: <redirect-2544396@logan.com>
From: "Bob Jude" <bobjude@charter.net>
References: <list-2543953@logan.com>
Subject: Antenna Measurements
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Charles Patton,
Congratulations on keeping us straight thinking about antenna measurements.
On this forum, when some one makes statements clearly outside their area of
expertise, it is good to hear from some one that really knows the subject.
Bob Jude
N65BJ


> Brent,
I'm sorry, but you have to be careful about making this statement. The
only thing that a low VSWR guarantees is maximum power transfer from the
source if it's impedance is that of the VSWR measuring device. It
absolutely does not guarantee radiation efficiency. It is that in most
circumstances with similar style antennas, the radiation efficiency of
the antenna is similar, therefore more power in is more power radiated.

Without doing antenna range type measurements, I am concerned with using
carbon fiber as your ground plane. There is the real possibility that
you can get a match to the cable, and dissipate a significant amount of
RF in the resistive carbon. You could have good VSWR, but lowered
radiation efficiency. This would also translate to a lower receiving
antenna efficiency too.

Charles R. Patton
LNC2 360JM