Automatic Direction Finding Equipment (ADF) & Transponders

Question 1

What is the frequency range of an aircraft’s Automatic Direction Finding (ADF) equipment?

Answer 1

190 kHz to 1750 kHz

Question 2

What is meant by the term “night effect” when using an aircraft’s Automatic Direction Finding (ADF) equipment? Nigh effect refers to the fact that:

Answer 2

Non Directional Beacon (NDB) transmissions can bounce-off the Earth’s ionosphere at night and be received at almost any direction.

Question 3

What are the transmit and receive frequencies of an aircraft’s mode C transponder operating in the Air Traffic Control RADAR Beacon System (ATCRBS)?

Answer 3

Transmit at 1090 MHz, and receive at 1030 MHz

Question 4

In addition to duplicating the functions of a mode C transponder, an aircraft’s mode S transponder can also provide:

Answer 4

Mid-Air collision avoidance capabilities.

Question 5

What type of encoding is used in an aircraft’s mode C transponder transmission to a ground station of the Air Traffic Control RADAR Beacon System (ATCRBS)?

Answer 5

Pulse position modulation.

Question 6

Choose the only correct statement about an aircraft’s Automatic Direction Finding (ADF) equipment.

Answer 6

An aircraft’s AD antennas can receive transmissions that are over the Earth’s horizon (sometimes several hundred miles away) since these signals will follow the curvature of the Earth.