What are the two main categories of transmission lines?

The two main categories of transmission lines are categorized as balanced lines and unbalanced lines. This classification is important because it affects how the lines interact with signals and the environment around them. Balanced lines have equal impedance on both conductors and are generally used to minimize electromagnetic interference. They are often associated with two-wire systems, where the currents are equal and opposite, which helps in reducing noise and improving performance.

In contrast, unbalanced lines typically have a single conductor and a ground reference, leading to a higher susceptibility to external noise and interference. This is typical for coaxial cables, which have a central conductor surrounded by a dielectric and an outer conductor that serves as a shield.

Understanding the difference between balanced and unbalanced lines is crucial for engineers and technicians in selecting the appropriate type of transmission line for various applications, ensuring efficient and reliable signal transmission.