RigExpert AA-35 ZOOM - Coaxial lines

RigExpert AA-35 ZOOM
Adjusting the antenna
When the measurement diagnoses that the antenna is off the desired frequency, the
analyzer can help in adjusting it. Physical dimensions of a simple antenna (such as a
dipole) can be adjusted knowing the actual resonant frequency and the desired one.
Other types of antennas may contain more than one element to adjust (including coils,
filters, etc.), so this method will not work. Instead, you may use the SWR mode, the
All parameters mode or the Smith chart mode to continuously see the results while
adjusting various parameters of the antenna.
Coaxial lines
Open- and short-circuited cables
The pictures on the right show R and
X charts for a piece of cable with
open- and short-circuited far end. A
resonant frequency is a point at which X
(reactance) equals to zero:
• In the open-circuited case, resonant
frequencies correspond to (left
to right) 1/4, 3/4, 5/4, etc. of the
wavelength in this cable;
• For the short-circuited cable, these
points are located at 1/2, 1, 3/2, etc.
of the wavelength.
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