Concentric Transmission Lines


Characteristic impedance in ohms is given by
Rf resistance in ohms per foot of copper line,
is given by
Attenuation in decibels per foot of line,
is given by


Where: 
Z
r
a
d1
d2
f

=
=
=
=
=
=

characteristic impedance in ohms,
radio frequency resistance in ohms per foot of
copper line,
attenuation in decibels per foot of
line,
the inside diameter of the outer
conductor, expressed in inches,
the outside diameter of the inner
conductor, expressed in inches,
frequency in megacycles.

TwoWire Open Air Transmission Lines

Characteristic impedance in ohms is given by
Inductance in micro henrys per foot of line is
given by
Capacitance in micromicrofarads per foot of line
is given by




Attenuation in decibels per foot of wire is given
by
Rf resistance in Ohms per loopfoot of
wire, is given by


Where: 
Z
D
d
L
C
db
Rf
f

=
=
=
=
=
=
=
=

characteristic impedance in ohms,
spacing between wire centers in inches,
the diameter of the conductors in inches,
inductance in microhenrys per foot of
line, capacitance in micromicrofarads
per foot of line,
attenuation in decibels per foot of wire,
rf resistance in ohms per loopfoot of
wire, frequency in megacycles.

Vertical Antenna


The capacitance
of a vertical antenna, shorter than onequarter
wave length at its operating
frequency, is given by


Where: 
Ca
l
d
f
e

=
=
=
=
=

capacitance og the antenna in micromicrofarads,
height of antenna in feet,
diameter of antenna conductor in inches,
frequency in megacycles.
2.718 (the base of the natural system of logarithms).

