GROL General Radiotelephone 3

Question 1

What is the primary purpose of the Global Maritime Distress and Safety System (GMDSS)?

Accepted Answer

To automate distress alerting and improve coordination of SAR operations

Answer

To provide commercial ship-to-shore telephone service

Answer

To replace VHF channels for routine port operations

Answer

To provide weather routing advice to vessel masters

Question 2

What is the internationally designated distress frequency for MF (medium frequency) radiotelephony?

Accepted Answer

2182 kHz

Answer

156.8 MHz (Channel 16)

Answer

406 MHz

Answer

8291 kHz

Question 3

In a superheterodyne receiver, what is the purpose of the IF (intermediate frequency) stage?

Accepted Answer

To amplify and filter the signal at a fixed, lower frequency for better selectivity

Answer

To convert the received RF signal directly to audio

Answer

To mix the incoming signal with the local oscillator

Answer

To provide automatic frequency control of the local oscillator

Question 4

Which antenna has a radiation pattern that is omnidirectional in the horizontal plane?

Accepted Answer

Vertical whip antenna

Answer

Yagi-Uda antenna

Answer

Corner reflector antenna

Answer

Rhombic antenna

Question 5

What does the term 'selectivity' refer to in a radio receiver?

Accepted Answer

The ability to reject adjacent channel interference

Answer

The ability to detect very weak signals

Answer

The range of frequencies the receiver can tune

Answer

The ratio of signal power to noise power at the output

Question 6

What safety precaution must be observed when working on a transmitter's high-voltage power supply?

Accepted Answer

Work with one hand in your pocket to avoid creating a path across the chest

Answer

Wear rubber-soled shoes only

Answer

Always use a wooden stick to change settings

Answer

Remove the antenna before energizing

Question 7

What is the main advantage of using SSB over double-sideband AM for long-distance voice communication?

Accepted Answer

SSB requires less bandwidth and transmits all power in one sideband

Answer

SSB has a wider bandwidth allowing higher audio quality

Answer

SSB is immune to selective fading on HF bands

Answer

SSB equipment is simpler and cheaper to manufacture