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Question 1

Frequency Range

Answer 1

Ex low 3khz
V low 3-30khz
Low 30-300Khz
Med 300-3 mhz
High 3-30mhz
V high 30-300mhz
Ultra high 300-3ghz
Super h 3-30ghz
Ex h 30-300ghz

Question 2

ehf

Answer 2

fire control radar (CIWS)

alternate IP band

Question 3

shf

Answer 3

satellite comms.

Question 4

UHF

Answer 4

los circuits

iridium

Question 5

VHF

Answer 5

green gear. SINCGARS, surface fire support

Question 6

HF

Answer 6

point to point. ship to shore. ground to air. FBS

Question 7

MF

Answer 7

AM radio

Question 8

LF

Answer 8

fleet multichannel broadcast channel

Question 9

VLF

Answer 9

submarines near the surface

Question 10

ELF

Answer 10

deeply submerged

Question 11

What is frequency?

Answer 11

number of cycles in a unit of time. measured in hertz when it comes to radio waves.

Question 12

what is wavelength?

Answer 12

distance spaced occupied by one cycle of a radio wave at any given moment. measure of crest of wave.

Question 13

ducting

Answer 13

trapping or propagation of an RG wave between two layers of the earth atmosphere.

Question 14

refraction.

Answer 14

change in direction of a wave due to a change in its speed.

Question 15

multiplexing

Answer 15

simultaneous transmission of 2 or more signals over a common carrier wave.

Question 16

bandwidth

Answer 16

amount of space in the frequency spectrum used by a given signal

Question 17

keying

Answer 17

actively using a line

Question 18

azimuth and elevation angle

Answer 18

azimuth is the horizontal angle measured clockwise from aa north base line or meridian. elevation angle is the angular heigh of the sun in the sky measured vertically from the horizontal

Question 19

Troposphere

Answer 19

lowest layer of atmosphere. surface to 10km.

Question 20

Stratosphere

Answer 20

2nd layer of atmosphere. relatively calm layer with little temperature change

Question 21

ionosphere

Answer 21

extends upward from about 31.1 miles to a heigh of about 250 mioes. 4 cloud-like layers of electrically charged ions which enable radio waves to be proagated great distances. BLOS circuits.

Question 22

how does frequency relate to the atmosphere

Answer 22

the higher the frequency the lower the rate of refraction

Question 23

radio waves relate to the atmosphere how?

Answer 23

ground waves and sky waves are the 2 ways electromagnetic energy travels between 2 antennas.

Question 24

USB

Answer 24

signal components above the carrier frequency

Question 25

LSB

Answer 25

signal components below the carrier frequency

Question 26

CW

Answer 26

electromagnetic wave of constant amplitude and frequency.

Question 27

Amplitude modulation

Answer 27

varying strength of a transmitted signal in relation to the info being sent.

Question 28

Frequency modulation

Answer 28

changing the frequency of a transmitted signal

Question 29

RADAR

Answer 29

radio detection and ranging

Question 30

Pulse repetition interval

Answer 30

time elapsed from the beginning of one pulse to the beginning of next pulse

Question 31

PRF - Pulse repition frequence

Answer 31

number of pulses per time unit

Question 32

Half duplex

Answer 32

transmit and recieve not at same time

Question 33

Full duplex

Answer 33

transmit and recieve simultaneously

Question 34

simplex

Answer 34

send or recieve only

Question 35

broadcast

Answer 35

sending messages only to multiple recieving stations.