Transmission Lines

The amount of loss in the signal strength as it propagates throughout a transmission line is called

• return loss

• SWR

• attenuation

• fading

The unwanted coupling caused by overlapping electric and magnetic fields

• Cross talk

• EMI

• Coupling loss

• Noise

The characteristic impedance of a transmission line is determined by the following factors except

• Conductor diameter

• Operating frequency

• Dielectric constant of the insulator

• None of the above

The characteristic impedance of a cable

• Increases with length

• Increases with frequency

• Increases with voltage

• None of the above

The velocity factor of a cable depends on

• the wire resistance

• the dielectric constant

• The inductance per foot

• All of the above

Compared to a 300-ohm line, the loss of a 50-ohm cable carrying the same power

• Would be less

• Would be more

• Would be the same

• Cannot be compared

Two 2-mm-diameter wires held 6 cm apart center-to-center has a characteristic impedance of (a)   ohms.(whole number)

What is the SWR along a transmission line having a characteristic impedance of 75 Ω and a load impedance of 300 Ω?

(a)  

Determine the length in feet of one-quarter wavelength coaxial cable with velocity factor of 0.8 at a frequency of 49 MHz. (2 decimal places)

(a)  

A transmission line has an SWR of 1.65. The power applied to the line is 50 W. What is the amount of reflected power? (Whole number)

(a)