On Fri, 04 Feb 2005 13:28:21 -0500, Buck wrote:
I want to test a couple of antenna designs and compare them to a
dipole antenna.
I am wondering if my idea is a good way to measure gain or loss from
an antenna. Here goes:
Create a place in which to install the test antenna which will be
consistent. For example, 40 foot high between two power poles (no
power lines etc, though.)
Setup a fixed location with a Field Strength Meter (FSM) that has a
fixed antenna for testing at that location.
Hang a dipole (the reference antenna) and transmit a signal that can
be calibrated to a fixed location on the FSM. Then hang the
experimental antenna in place of the dipole. Take the measurements
without changing anything from the rig. Measuring the power output
required to meet the same setting on the FSM as the dipole should give
me a fair idea about the gain or loss from the experimental antenna.
or maybe not.
What am I overlooking?
Thanks
Buck
N4PGW
If you are trying to get a feel for the pattern of the antennas in
"the real workd" you want to have your receiving antenna far enough
away to be making far field measurements. I don't have a definition
at hand, but it think it's somewhere between 5 and 20 wavelengths.
Regards,
Ed
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