1 TRANSMISSION LINES CIRCUITS

1-TRANSMISSION LINE
Transmission line is any electrically, suitable confinement used to guide the flow of energy physically between two points in a system.
Basic transmission line conductors are:-
Two- wave parallel lines
Coaxial lines and the
Wave guide and fiber optics
Both two-wave line and coaxial cables have the similar electrical properties. They have wire Resistance (R) and are inductive (L) at high frequencies.
The insulation separation forms capacitance (C) and insulating material or air will only contribute to conductance (G)
This can be elaborated in the following T- network, where series impedance (R+jwC) is divided into two halves, and shunt impendence (G+jwC is across line at its centre.
The major use of the transmission line circuits in Radio and Television transmission is for enabling of effective or proper designing of cable type and size. The same applies to the antenna designing.
These lines are meant for transferring signals from one point to another without any loss.
Others like Lecher lines can create resonant circuit at HF/VHF and UHE/VHF where resonant activities are active.