3-48
SUMMARY
This chapter has presented information on the characteristics of transmission lines. The information
that follows summarizes the important points of this chapter.
TRANSMISSION LINES are devices for guiding electrical energy from one point to another.
INPUT IMPEDANCE is the ratio of voltage to current at the input end of a transmission line.
OUTPUT IMPEDANCE is the ratio of voltage to current at the output end of the line.
TWO-WIRE OPEN LINES are parallel lines and have uses such as power lines, rural telephone
lines, and telegraph lines. This type of line has high radiation losses and is subject to noise pickup.
TWIN LEAD has parallel lines and is most often used to connect televisions to their antennas.
A TWISTED PAIR consists of two insulated wires twisted together. This line has high insulation
loss.