11. A shipboard equipment which measures the distance between the ship’s bottom and the ocean floor. A. Fathometer B. Echosounder C. LORAN D. SONAR Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option D No explanation is given for this question Let's Discuss on Board
12. Rainfall is an important factor for fading of radio waves at frequencies above A. 10 GHz B. 100 GHz C. 1 GHz D. 100 MHz Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option A No explanation is given for this question Let's Discuss on Board
13. In a pulsed radar set, the STC circuit is used to A. Improve the target bearing resolution B. Increases receiver sensitivity for echoes from targets C. Vary the pulse frequency in order to control the maximum target D. Reduce interference from the effects of sea return Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option D No explanation is given for this question Let's Discuss on Board
14. Which causes multipath or frequency selective fading? A. Small reflector B. Nearer reflector C. Further reflector D. Large reflector Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option D No explanation is given for this question Let's Discuss on Board
15. If k-factor is greater than 1, the array beam is bent A. Away from the earth B. Towards the ionosphere, C. Towards the earth D. Towards the outer space Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option C No explanation is given for this question Let's Discuss on Board
16. Klystron oscillators are most often used in the frequency range of A. 300 to 3000 MHz B. 3000 to 30000 MHz C. 30 to 30000 MHz D. 10 to 10000 MHz Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option B No explanation is given for this question Let's Discuss on Board
17. Which of the following permits a microwave signal to travel in one direction with virtually no loss, but severely attenuates any signal attempting to travel in the reverse direction? A. Isolator B. Wave trap C. Tunnel diode D. Circulator Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option A No explanation is given for this question Let's Discuss on Board
18. The main frequency determining element of a klystron is A. The repeller voltage B. The accelerating voltage C. Its resonant cavity D. Its mode of operation Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option C No explanation is given for this question Let's Discuss on Board
19. As the electron beam moves through a klystron’s intercavity drift space A. Frequency modulation at the input cavity creates velocity modulation at the output cavity B. Velocity modulation at the input cavity creates density modulation at the output cavity C. Density modulation at the input cavity creates velocity modulation at the output cavity D. Phase modulation at the input cavity creates velocity modulation at the output cavity. Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option B No explanation is given for this question Let's Discuss on Board
20. In a pulsed radar set, the function of the duplexer is to A. Aid in calibrating the display unit B. Prevent frequency drift in the klystron C. Allow the transmitter and the receiver to operate from a common antenna D. All of these Answer & Solution Discuss in Board Save for Later Answer & Solution Answer: Option C No explanation is given for this question Let's Discuss on Board
