The Packet Radio
“
2 N 1
”
Handbook
by
Buck Rogers
K4ABT
Section 1
;
Packet Radio “The Basics
”
Section 2
;
The X1J4 System Node Operator’s (SNO) Handbook
Section 1
;
Packet Radio “The Basics
”
A Packet Primer for the new Packeteer
__ Page 0
Chapter Three
Antennas For Packet
I'm not suggesting that any digital radio user should select one antenna over another. Use whatever you have, or choose the
antenna that best favors your needs and environment.
This chapter deals with the specifics related to various types of antenna. We will consider everything from an isotropic radiator
(Dipole) to a J-Pole.
Packet radio is one of those communications modes that will reflect on the system operator if he or she fails to provide the antenna
that has the best radiating and capture effect to it. In fact, if the antenna is not constructed and erected so as to provide good capture
to signals and have the
lowest noise component
with respect to terrestrial
noise, then no one is to
blame except the operator
who is in charge of the
installation.
I am as meticulous as A.J.
the day before race day.
Don't just walk the race
track, look for the bumps
and crevices. The antenna
for your packet station is
about to become your
doorway to the world.
Every one who has spent any
time around me will
affirm that, "Buck won't
skimp when it comes to
his
antenna."
I am very particular where
my antennas are
concerned. When I go to
buy cable and connectors,
I purchase the best available
coax and connectors.
When I go to buy cable or
connectors, I specify silver
flashed connectors and cable
of the best quality. Over
the years, that is the part of
my station that will get the
least attention after it is
installed, so I want it to
withstand the elements and
provide dependable
communications for a long
time.
I am very picky about the
antennas and associated
components of my antenna system. With over forty years as a amateur, and over forty five years as a Senior Telecommunications
Engineer, I’ve learned a very valuable lesson early on. SIGNAL QUALITY begins at the tip of the antenna, and it travels down
through the transmission-line and reflects off the operator at the other end. Let your reflection be a good one.
RADIATION and RESONANCE:
Antennas can be constructed to radiate with directional, omni- directional, and bi-directional patterns.
The kind of pattern desired, depends on the coverage area requirements. Likewise, the type antenna selected, will determine the
kind of pattern you will have. Another major factor in antenna selection and installation is the distance above the ground that an
antenna is suspended.
Antenna theory as related to antennas suspended in free space states simply that the ground below will provide a reflection or
mirror effect. This mirror effect gives an antenna the appearance of having greater gain when the antenna is mounted at distances
that are "in- phase", or a given wavelength above the earth. The greater the height, the greater the gain.
