Att Test 10 Et

Front 1

What type of jammer generates RF noise in a particular band or frequency channel to change the signal to noise ratio of a radar receiver?

Back 1

Spot noise

Front 2

What are the operational pressures of high and low power dry air systems?

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Back 2

25 to 35 psi high and 1 to 8 psi low

Front 3

What is the standard FM broadcast IF?

Back 3

10.7 MHz

Front 4

What is dry air used in a waveguide for?

Back 4

To prevent arching

Front 5

What is reciprocity?

Back 5

The ability of an antenna to act as a transmitting or receiving antenna

Front 6

What is the hallmark of standard SSB?

Back 6

Long transmission range with minimal power use

Front 7

When/why is the bandwidth of the NBFM communication system reduced?

Back 7

To accommodate signal and voice transmission

Front 8

What does a type 1 dehydrator use to remove liquid and oil?

Back 8

Refrigerant

Front 9

What is the primary factor affecting radar accuracy?

Back 9

Radar system resolution

Front 10

The length of LOS is known as?

Back 10

Range

Front 11

What are the benefits of frequency synthesis?

Back 11

Smaller size, greater frequency stability, and versatility to interface with microprocessors

Front 12

What enables the HF system to communicate over long ranges?

Back 12

High power transmitters, sensitive receivers, and ionospheric conditions

Front 13

The maximum frequency just below the escape point?

Back 13

Critical frequency

Front 14

When the error voltage from the low pass filter ____ the VCO output frequency ______.

Back 14

Increases, Increases

Front 15

When intelligence is injected into the final RF power amplifier it is considered to be ______.

Back 15

High level modulation

Front 16

The higher the sun ____.

Back 16

The higher the frequency

Front 17

What form of SSB is commonly used in the military?

Back 17

ISB

Front 18

RF energy reflected from an object is called?

Back 18

Echo

Front 19

What is also a popular communications format with the U.S. Military?

Back 19

NBFM

Front 20

When are standing waves created?

Back 20

When there is an impedance mismatch in the transmission system

Front 21

Where is the double conversion process used?

Back 21

In communication receivers

Front 22

What are the advantages of FM?

Back 22

Less interference between stations, greater noise suppression, and reduce transmitter power to cover an assigned area.

Front 23

The components of an AM signal are ____?

Back 23

USB, Carrier, LSB

Front 24

What type of loss is due to high frequency currents flowing near th outer surface of the conductor?

Back 24

Skin effect loss

Front 25

What are FM sidebands that contain the majority of power called?

Back 25

Significant Sidebands

Front 26

How many IF amplifier stages does a FM receiver normally have?

Back 26

2 or more

Front 27

Distortion is commonly caused by ____?

Back 27

Over driven amplifiers

Front 28

When a portion of electric energy is lost to the atmosphere, not a nearby object, it is called?

Back 28

Radiation Loss

Front 29

What radar receiver circuit produces the IF frequency?

Back 29

The MIxer

Front 30

What is the most commonly used reference level in the decibel measurement system for radar?

Back 30

1 Miliwatt

Front 31

The combat ECM use _____.

Back 31

ECCM

Front 32

The citizen band frequency range is?

Back 32

26.965-27.405 MHz

Front 33

What type of loss is due to the capacitance formed between transmission lines?

Back 33

Dielectric Loss

Front 34

If the VCO frequency is lagging the reference frequency; the DC error voltage?

Back 34

Increases

Front 35

What are the noise spikes in the FM removed by?

Back 35

The limiter

Front 36

The phase lock loop circuit is?

Back 36

A closed circuit

Front 37

The waveguide is defined as a system of material boundaries capable of guiding?

Back 37

Electromagnetic energy

Front 38

Why do radio waves have to be converted to sound waves?

Back 38

Electromagnetic waves have no effect on the human ear

Front 39

What form of SSB is used with television video signals?

Back 39

Vestibical sidebands

Front 40

True or False, FM receivers must have an RF amplifier?

Back 40

True

Front 41

What form of SSB is commonly used by amateur radio operators?

Back 41

Standard SSB

Front 42

The local oscillator in the AM receivers is always tuned to?

Back 42

45KHz above the tuned RF

Front 43

What type of circuit demodulates FM signals according to frequency variations produced by the difference between the FM input frequency and VCO frequency?

Back 43

Phase lock loop

Front 44

The VCO frequency can lock onto the reference frequency when the reference signals is?

Back 44

Between the upper and lower cutoff frequency

Front 45

Radio and light waves are ______ which are futher classified as _______.

Back 45

Transverse waves, electromagnetic waves

Front 46

Adding a reflector to a horn antenna increases?

Back 46

Power gain and directivity

Front 47

What is RF energy reflected from an object called?

Back 47

Echo

Front 48

What is not a component of a typical communications systems?

Back 48

Satellite Up-link

Front 49

Why are some equipment enclosures hermatically sealed?

Back 49

To prevent the entrance of moisture

Front 50

How is electromagnetic energy produced?

Back 50

By current flowing through a conductor

Front 51

Which RADAR receiver component converts the IF pulses to video pulses?

Back 51

Video detector

Front 52

True or False; The AM receiver uses an RF amplifier?

Back 52

False

Front 53

What type of an antenna would a RADAR system use to determine the bearing of an object?

Back 53

An antenna that has a narrow horizontal beam width

Front 54

Two objects at the same range must be separated by _____ to be separately distinguishable by the radar systems?

Back 54

At least one beam width

Front 55

What is the physical handling and installation of waveguides called?

Back 55

Plumbing

Front 56

The _____ the frequency wave, the more rapidly the wave is ______ by given degree of ionization?

Back 56

Lower, refracted

Front 57

A 30 Khz bandwidth is at the ______ end of normal bandwidth range?

Back 57

High

Front 58

Modulation may best be defined as?

Back 58



The superimposition of low frequency info on a high frequency carrier signal

Front 59

What is characteristic impedance?

Back 59

Distributed inductance and capacitance of the line

Front 60

Balanced modulators produced?

Back 60

Only the sum and difference

Front 61

Electromagnetic Energy is produced by ______.

Back 61

Current flowing through a conductor

Front 62

Effective suppression of the carrier requires?

Back 62

Highly matched components

Front 63

The RF Energy reflected from an object provides ____ to the radar system?

Back 63

Bearing, range, elevation, and velocity

Front 64

The "B" dimensions determines the ______ handling capability of a waveguide

Back 64

Power

Front 65

In frequency modulation the intelligence is located in the ____.

Back 65

Frequency

Front 66

What does indirect synthesis use?

Back 66

PLL's and VCO's

Front 67

What terms are associated with the limiter?

Back 67

Threshold, quieting, or limiting knee voltage

Front 68

Incident traveling waves are?

Back 68

The RF signals traveling through a transmission line

Front 69

The input signals to the phase comparator are the?

Back 69

Reference signal and VCO signal

Front 70

The reference signal is applied to the ____.

Back 70

Phase comparator

Front 71

What is the purpose of the dust filter in the dry air system?

Back 71

To prevent desiccant and dust from contaminating the dry air system

Front 72

What is the main purpose of the HF system?

Back 72

To provide long range high frequency surface-to-surface, surface-to-air, and air-to-air radio communication

Front 73

What effect does FTC have on receiver gain?

Back 73

None

Front 74

How is an antennas power gain measured?

Back 74

In relation to a reference antenna

Front 75

Narrow-band FM is primarily used for

Back 75

Voice communications

Front 76

What are the factors that influence Ionospheric refraction?

Back 76

Ionospheric density, transmitter operating frequency, and angle at which radio waves strike the ionosphere

Front 77

What is the least efficient type of equipment cooling?

Back 77

Convection

Front 78

What type of loss is due to resistance, respecially in long waves?

Back 78

Copper Loss

Front 79

True or False; Receivers may have more than one IF stage.

Back 79

True

Front 80

Frequency at which energy transmitted directly upward will escape directly into space?

Back 80

Escape point

Front 81

Each layer of the ionsphere has a maximum frequency that it will refract, known as the?

Back 81

Critical frequency

Front 82

The heterodyning process creates?

Back 82

The original two frequency, their sum and difference

Front 83

The "A" dimension determines the _____ handling capabilty of a waveguide.

Back 83

Frequency

Front 84

What is the unit of measurement for radar?

Back 84

1 miliwatt

Front 85

Ceramic filters have a ____ response curve, but a ____ in gain.

Back 85

Sharp, Loss

Front 86

Which is an advantage of SSB transmission?

Back 86

Makes efficient use of the RF spectrum

Front 87

Superheterodyne is _______.

Back 87

The most commonly used in radar systems

Front 88

The frequency at the output of the IF amp should be?

Back 88

455 KHz

Front 89

What is the filter's primary goal in PLL's?

Back 89

To remove the harmonic components of the reference frequency

Front 90

What is the definition of wave propagation?

Back 90

The movement of the electromagnetic wave pass through a medium

Front 91

The USB and LSB are always ____.

Back 91

180 degrees out of phase

Front 92

Commonly caused by overdriven amplifiers?

Back 92

Distortion

Front 93

Where is a truncated parabolic antenna normally used?

Back 93

In a radar microwave system

Front 94

The length of the line of sight is ____.

Back 94

Range

Front 95

Demodulation occurs when the ____.

Back 95

"Intelligence" is extracted from the carrier

Front 96

Selectivity is defined as ____.

Back 96

A receivers ability to tune to a specific frequency while rejecting others

Front 97

The CW Jammer transmits _____ unmodulated jamming signals to change the signal-to-noise ratio of a radar receiver

Back 97

Constant - Amplitude , Constant - Frequency

Front 98

The frequency of a radio wave must be ____ to compensate for changes in the ionosphere during the day.

Back 98

Increased

Front 99

What is the maximum frequency that each inosphere will refract?

Back 99

Critical Frequency

Front 100

What is active ECM sometimes referred to as?

Back 100

Jamming

Front 101

Where is the intelligence in an AM signal located?

Back 101

Both in the sum of the original carrier and audio frequencies, and in the difference of the original carrier and audio frequencies.

Front 102

A type 1 dehydrator uses refigerant to remove _____.

Back 102

Liquid and oil

Front 103

The primary system provides the initial source of coolling water that can either be ___.

Back 103

Seawater or chilled water

Front 104

The Secondary system transfers ___?

Back 104

The heat load from the electronic equipment

Front 105

Amplitude modulation may be defined as _____.

Back 105

Varying the carrier amplitude with the instantaneous changes of the audio signal

Front 106

The FM receiver's ability to select the stronger of the 2 signals with the same frequency is known as _____.

Back 106

The Capture Effect