A & P Flashcards
What is the speed of light in meters per second?
300,000,000 mps
What is the civilian HF frequency band?
3 MHz to 30 MHz
How many 5khz channels would you get in the UHF bandwidth? (Remember-kilohertz: 1000 hertz, megahertz: 1000, 000)
UHF bandwidth is 300-3000Mhz giving 2700 MHz bandwidth; therefore answer should be 2700, 000, 000 divided by 5000 equals: 5400 channels
What is the relationship between Wavelength and Frequency?
Higher Frequency shorter wavelength
What is the polarization of a SATCOM antenna?
Polarization of a Satcom antenna is circular
Name the three components of a radio wave?
Frequency ( f )
Wavelength ( lambda )
Velocity ( v )
How will the ionosphere affect at night effect UHF Tacsat communication?
Less resistance and refraction than than during the day time. therefore less interference and potential clearer Tacsat comm
How will the ionosphere affect HF comms at night?
Higher frequencies will pass through the ionosphere and less will be reflected back to the surface
Name the three types of radio wave?
Skywave
Space wave - Direct wave
- Ground reflected
Surface wave
Give one predictable Ionospheric variation?
Geographical
Seasonal
Daily
Sunspot cycle
Give one unpredictable Ionospheric variation?
Solar flares
Magnetic storms
Sporadic E
What is the symbol for writing wavelength and its name?
LAMBDA
Name 2 factors effecting surface wave?
Polarisation Frequency Ground Terrain Obstacles
Factors effecting space wave?
Antenna height
Refraction in lower atmosphere
Obstacles terrain
Name the layers of the ionosphere and what happens at night?
F2
F1
E
D
Turn into one F layer at night
Explain skip zone?
The zone where surface wave stops and sky wave returns to Earth
Explain skip distance?
Distance where the wave leaves antenna to where it first returns to Earth