This set of Avionics Multiple Choice Questions & Answers (MCQs) focuses on “Point Source Radio Systems”.
1. Which of the following is not true with respect to airborne direction finder?
a) They are also called homing adapters
b) Uses the simplest of systems
c) Very low error
d) Take bearings on the ground transmitter
2. Which of the following type of direction finder has a system that rotates the loop, using a servo system until a null is found?
a) Fixed loop
b) Rotatable loop
c) Rotating loop
d) Fixed, crossed loop
3. Which type of direction finders takes bearings on airborne transmitters and advice the aircraft of its bearing from the ground station?
a) Ground based
b) Airborne direction finders
c) Homing adapters
d) Homing beacon
4. Which of the following is not true with respect to loop antennas?
a) Horizontal polarization is assumed
b) Resonance is achieved by a variable capacitor
c) The horizontal antenna pattern is a figure of eight
d) The currents are equal in amplitude and phase when the antenna is 90° with the transmitted signal
5. What is used to combine the output of the two fixed loop antenna that are placed at right angles to each other?
b) Spectrum analyzer
6. Which of the following is not an advantage of NDB?
c) Accuracy depends on airborne equipment
d) No mountain and night effect
7. What can be added to reduce signal ambiguity in a loop antenna?
a) Low noise amplifier
c) Sense antenna
d) Increase the antenna size
8. The area of reduced signal strength in a non directional beacon is called as ______
a) Cone of silence
b) Zero reception zone
c) Zone of silence
d) Non radio zone
9. What frequency does the marker beacon use for fixes along the airways?
10. What is the frequency of rotation of the directional beam in a VOR?
11. What is the time gap between each pulse in an interrogation pulse pair for a DME?
12. Which of the following can be used to reinforce the upward beam in a marker beacon?
d) Vertical polarization
13. Which of the following generates the same field pattern as a vertical dipole antenna?
a) Yagi antenna
b) Helix antenna
c) Alford loop
d) Microstrip antenna
14. Why are pulse pairs used in DME instead of single pulses?
a) Reduce interference
b) Better range
c) Reduced noise
15. What is the frequency in which the DME transmits?
a) 50Mhz above or below the received frequency
b) 20Mhz above the received frequency
c) 40Mhz below the received frequency
d) 63Mhz above or below the received frequency