ATSEP BASIC ATC EXAM PREP GUIDE 2026
AIR TRAFFIC CONTROL SYSTEMS
CONCEPTS AND SOLVED ITEMS
◉ What is the method to change properties like amplitude or
frequency of a periodic wave to convey a message to it called?
Answer: Modulation
◉ What is meant by refraction of a radio wave?
Answer: The change in direction of propagation of a wave due to
change in its transmission medium
◉ What is meant by a duplex communication system?
Answer: Telecommunication between two stations can take place in
both directions simultaneously
◉ What aeronautical service is used between 118 - 137 MHz?
Answer: Voice communication on the VHF band
◉ What is the purpose of the PTT button on a radio?
Answer: To activate the radio transmitter
, ◉ What is SELCAL?
Answer: A selective calling system that allows a ground radio
operator to alert an aircrew that the operator wishes to
communicate with that aircraft.
◉ What communication system allows a controller and an aircraft to
communicate via data link text messages
Answer: CPDLC
◉ What is the functionality of the radio receiver?
Answer: Amplify and demodulate the signal to make it audible and
pass it to the loudspeakers
◉ Which connections are normally used for ground-ground
communication between ATS units?
Answer: Telephone or intercom connections
◉ What is the message handling system used to exchange for
instance flight plans and MET messages between ATS units called?
Answer: AFTN
◉ What is an example of the aeronautical fixed telecommunication
service?
Answer: AMHS
AIR TRAFFIC CONTROL SYSTEMS
CONCEPTS AND SOLVED ITEMS
◉ What is the method to change properties like amplitude or
frequency of a periodic wave to convey a message to it called?
Answer: Modulation
◉ What is meant by refraction of a radio wave?
Answer: The change in direction of propagation of a wave due to
change in its transmission medium
◉ What is meant by a duplex communication system?
Answer: Telecommunication between two stations can take place in
both directions simultaneously
◉ What aeronautical service is used between 118 - 137 MHz?
Answer: Voice communication on the VHF band
◉ What is the purpose of the PTT button on a radio?
Answer: To activate the radio transmitter
, ◉ What is SELCAL?
Answer: A selective calling system that allows a ground radio
operator to alert an aircrew that the operator wishes to
communicate with that aircraft.
◉ What communication system allows a controller and an aircraft to
communicate via data link text messages
Answer: CPDLC
◉ What is the functionality of the radio receiver?
Answer: Amplify and demodulate the signal to make it audible and
pass it to the loudspeakers
◉ Which connections are normally used for ground-ground
communication between ATS units?
Answer: Telephone or intercom connections
◉ What is the message handling system used to exchange for
instance flight plans and MET messages between ATS units called?
Answer: AFTN
◉ What is an example of the aeronautical fixed telecommunication
service?
Answer: AMHS
