This set of Avionics Multiple Choice Questions & Answers (MCQs) focuses on “Standing Waves”.
1. Which of the following is not true regarding standing wave?
a) In a standing wave the energy moves towards the power source
b) In a standing wave power loss occurs
c) Standing waves do not affect signal strength
d) Standing waves are not desirable
2. What is the load on a transmission line?
a) 0 Ω
c) Some value between 0 and infinity
d) Some value between0 and 1
3. Which of the following does not cause standing waves?
a) Short circuit
b) Open circuit
c) High frequency high power signal
d) Impedance is not matched
4. The transmission line in which the resistive impedance is equal to the characteristic impedance is called _____
a) Matched lines
b) Paralleled lines
c) Balanced lines
d) Unbalanced lines
5. In an unmatched line the actual signal on the line is ___________
a) The sum of forward and reflected signals
b) The difference of forward and reflected signals
c) The product of forward and reflected signals
d) The modulus of forward signal
6. The ratio of the incident voltage wave Vi to the reflected voltage wave Vr is called the reflection coefficient.
7. How would the graph of wavelength vs voltage look like if the transmission line is matched (neglect resistive loss)?
a) Linearly increasing
b) Linearly decreasing
c) Exponentially decreasing
8. What is the Standing wave ratio if a 75Ω antenna load is connected to a 50Ω transmission line?
9. What is the reflection coefficient If a line is terminated in its characteristic impedance?
10. What is the resistive load if SWR= 3.05 and Zo =75Ω?
11. What percentage of power is reflected if the reflection coefficient is 0.5?