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37 Cards in this Set
- Front
- Back
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ELF (extremely low frequency) range
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3MHz-30Hz
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super low frequency (SLF)
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30Hz-300Hz
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ultra low frequency (ULF)
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300KHz-3KHz
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Very Low Frequency (VLF)
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10KHz-30KHz
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Low Frequency (LF)
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30KHz- 300KHz
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3MHz-30Hz
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High frequency (HF)
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30MHz-300MHz
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Ultra High frequency (UHF)
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300MHz-3GHz
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super high frequency (SHF)
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30GHz-300GHz
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extremely high frequency (EHF)
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what is frequency measured in?
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Hz
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define frequency.
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number of cycles per second
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ducting or trapping
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trapping of RF wave between two layers of the earth's atmosphere
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define wavelength
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distance in space occupied by one radio wave at any given time
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refraction
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when wave passes from one medium to another
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multiplexing
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transmission of two or more signals over common carrier wave
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modulation
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process of transmitting impressed intelligence in the form of compressed RF energy
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bandwidth
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difference between highest usable frequency and the lowest usable frequency
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keying
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transmit by morse or PTT
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3 main layers of the atmosphere
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troposphere
stratosphere ionosphere |
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USB (upper side band)
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all SUM frequencies above carrier
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LSB (lower side band)
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all DIFFERENCE frequencies below the carrier
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CW (carrier wave)
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Contains CENTER frequency of transmitted signal
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AM (amplitude modulation)
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signal varies in amplitude but RADIO FREQUENCY wave is kept constant
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FM ( Frequency Modulation)
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signal varies in FREQUENCY but amplitude kept constant
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air search
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detect and determine position, course and speed of air targets in relatively large area
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surface search
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keeps 360 degree of search pattern for all objects
and determines accurate ranges and bearings of surface objects |
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fire control
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narrow, circular beam pattern
used to track the position of target for development |
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Difference between OPELINT and TECHELINT
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OPELINT = concerned with info about foreign emitters and weapon systems associated with them
TECHELINT = concerned with info about electronics and weapons systems associated with them |
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half duplex
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1or 2 way communication, not at the same time
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duplex
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two way communication, at the same time
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simplex
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one way communication
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PRI
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pulse rep. interval
time from 1 radar pulse to he start of next pulse |
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PW
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pulse width
period of time radar is transmitting |
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BW
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frequency range of transmitter
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PRF
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pulse rep. frequency
# of pulses emitted in 1 second |
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scan
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movement of radar beam in definite pattern
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CW
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cont. wave
cont. hits targets |
