ATSEP.C TEST QUESTIONS AND ANSWERS
If you know them, you can easily calculate the angle of incidence needed for the
wave to return to the Earth. - ANSWER Virtual Height
F1 - ANSWER 90-150 miles
Critical frequency of F1 layer: 5 MHz
The highest frequency that will be returned to earth is the critical frequency.
The shortest distance from a TX measured along the earth's surface - ANSWER
Skip distance
If TX height equals RX height, what is the maximum distance between two
towers for LOS communication? - ANSWER 8 Hours
ANSWER to Maxwell's equation: "that a changing magnetic field will produce
an electric field and that a changing electric field will produce a magnetic field"
Because electric and magnetic fields are 90 degrees out of phase with time, they
only contain reactive energy. Only important in the local area of the antenna. -
ANSWER Induction field
Consists of lines of force that have detached from the antenna and are traveling
into space as an electromagnetic wave. Electric and magnetic fields are time-
phased. - ANSWER Radiation field
Occurs when two waves that left the same source and traveled on opposite paths
arrive at the same spot after being reflected by the earth. - ANSWER
Interference
Increases ground wave coverage - Antenna Gain.
3-30 GHz - SHF
If you know them, you can easily calculate the angle of incidence needed for the
wave to return to the Earth. - ANSWER Virtual Height
F1 - ANSWER 90-150 miles
Critical frequency of F1 layer: 5 MHz
The highest frequency that will be returned to earth is the critical frequency.
The shortest distance from a TX measured along the earth's surface - ANSWER
Skip distance
If TX height equals RX height, what is the maximum distance between two
towers for LOS communication? - ANSWER 8 Hours
ANSWER to Maxwell's equation: "that a changing magnetic field will produce
an electric field and that a changing electric field will produce a magnetic field"
Because electric and magnetic fields are 90 degrees out of phase with time, they
only contain reactive energy. Only important in the local area of the antenna. -
ANSWER Induction field
Consists of lines of force that have detached from the antenna and are traveling
into space as an electromagnetic wave. Electric and magnetic fields are time-
phased. - ANSWER Radiation field
Occurs when two waves that left the same source and traveled on opposite paths
arrive at the same spot after being reflected by the earth. - ANSWER
Interference
Increases ground wave coverage - Antenna Gain.
3-30 GHz - SHF
