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31 Cards in this Set
- Front
- Back
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What is the primary use of Extremely Low Frequency < 3kHz?
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ELF primarily communicates one way with Submarines
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What is the range for extremely low frequency communications?
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<3 kHz
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How far can extremely low range frequencies travel 3kHz?
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> 100 KM
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What is the primary use of Very Low Frequency communications 3-30 kHz?
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1. VLF communications are primarily used in the Northern Latitudes where ionospheric noise interrupts HF comms.
2. One way fleet communications and Navigation 3. Satcom |
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What are the back up uses of Very Low Frequency communications 3-30 kHz?
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1. Short wave coms blacked out by nuclear activity
2. World wide clock timing |
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How far can Very Low Frequency Communications travel?
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10-100 kM
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How far can Low Frequency communications travel?
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1-10 km
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What is the frequency range of Low Frequency?
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30- 300 kHz
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What are the disadvantages of Low Frequency communcations?
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1. Big equipment
2.$$$$$$ 3.Atmospheric noise interference at low geographic latitudes |
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How are Low Frequency Communications used?
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1. Radio communications in Northern Latitudes
2. Fleet broadcast when Ionospheric interferance occurs on HF frequencies |
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What is the frequency range for Medium Frequency?
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300kHz- 3 mHz
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How far can a medium frequency (300 kHz- 3 mHz) wavelength travel?
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100m - 1km
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What are the international distress signal frequencies?
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500 kHz 480 kHz
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What frequencies does commercial AM radio use?
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535 kHz- 1605 kHz
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What is the primary use of the lower end of the MF spectrum (300-500kHz)?
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lower portion of the mf band (300
to 500 kilohertz) are used primarily for ground-wave transmission for moderately long distances over water and for moderate to short distances over land. |
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What is the primary use of the upper end of the MF spectrum up to 3mHz?
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Transmission in the upper mf band is generally
limited to short-haul communications (400 miles or less). |
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What is the High Frequency range?
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3-30mHz
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What is the distance a HF wavelength can travel?
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10-100m
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What are the four primary uses of HF communcications?
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1. Point-to-point (Trunk ckt cnx) Link (txr/rx/cxn)
2. ship-shore 3.Ground-air 4. Fleet broadcast |
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What is an interesting trait of HF communications?
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Wavelengths bounce off the ionosphere created by the sun's radiation.
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What is the primary use of VHF communications?
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LOS not over the horizon Amphib OPS
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What is the primary use of UHF communication?
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Tactical voice communications ( ships traveling together)
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What is the frequency of VHF?
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30-300 mHz
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What is the distance a VHF wave travels?
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1-10 m
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What is the frequency of UHF?
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300 mHz- 3gHz
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What is the primary use of SHF?
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Radar and Satcom
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What is the primary use of EHF?
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Experimental Stage
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What is the frequency of SHF?
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3-30 gHz
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What is the frequency of EHF?
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30- 300gHz
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What is the distance a SHF wave travels?
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1-10cm
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What is the wavelength range of EHF?
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1mm-1cm
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