Formulas

Question 1

Radio Theory

Question 2

Wavelength

Answer 2

Lamda = C/F
C = 3 × 10^8
F = Frequency

Question 3

Depth of modulation

Answer 3

DOM = (Peak amplitude of audio signal / peak amplitude of carrier signal) × 100

Question 4

Sideband calculation

Answer 4

Carrier freq - Audio freq = bandwidth

Question 5

Radio wave range

Answer 5

Range(nm) = 1.25([root]Tx height(ft) + [root]Rx height (ft))

Question 6

ILS

Question 7

ILS ROD

ILS Height Passing

Answer 7

ROD = Theta × GS(miles per min) × 101.3

Height Passing = G/S × Range from touchdown(nm) × 101.3

Question 8

Radar

Question 9

Beam width

Answer 9

Beam width° = 70(lamda) / D
Where D = diameter of dish, lamda and D same units

Question 10

Max ambiguous range

Answer 10

Runamb = C / (2 × PRF)

Question 11

Range

Answer 11

Range(nm) = 81000 / PRF

Question 12

Power

Answer 12

New power ÷ old power = (new range ÷ old range)^2

Question 13

Cone of confusion

Answer 13

Diameter(nm) = Height above NDB(nm) × Tan50° × 2

Question 14

Cloud Top

Answer 14

Cloud Top = range(nm) × (tilt angle - 1/2beam width) × 100

Question 15

AWR minimum range

Answer 15

Half the length of the wave burst
Min range = (prf × pw) ÷ 2
pw = pulse width

Question 16

DME slant range using time after transmission

Answer 16

Distance = rate × time
Where:
Rate = C
Time = (total time - 50microseconds) / 2