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Flashcards in RADAR Deck (126):
1

The word "RADAR" is an acronym. What do the letters stand for?

Radio, Detection and Ranging

2

The Radars transmitted signal will travel how far?

Infinitely until absorbed,reflected or refracted

3

Radio Energy always travels how fast?

186,000 miles per second
Speed of Light

4

At what speed does both transmitted and received RADAR signals travel?

Constant Speed

4

At what speed does both transmitted and received RADAR signals travel?

Constant

5

No person should drive a vehicle on a highway at a speed greater than is reasonable and prudent under existing condition is known as?

Basic Speed Law

6

Prime Facie means?

"At first sight"

7

Does NC have a prime facie law?

No, it has the absolute speed law

8

What is the absolute speed law?

drive faster than a specific numeric speed

9

What elements make up the speed offense?

Driver Identification
Location
Speed
Conditions

10

With the oil embargo of 1973, Congress imposed what maximum speed in 1974?

55 mph

11

Frequency of a K-Band RADAR signal?

24.150 gigahertz

12

Frequency of a Ka-Band RADAR signal?

34.700 gigahertz

13

Ka-Band RADAR signals has a wave length of about?

4/5 centimeters

14

X-Band RADAR signal has a wave length of about?

3 centimeters

15

The RADAR signal's speed stays the same but its _________ and ___________ both change?

wave length and frequency

16

Relative motion will only occur when?

The RADAR stands still and the object moves or
The object stands still and the RADAR moves

17

If the RADAR and the object are both moving at different speeds or in different directions and the distance is changing between the two then there must be?

Relative Motion

18

What determines how much higher or lower the reflected signal's frequency will be?

speed of the relative motion

19

In stationary RADAR the true speed of the object can only be measured if the object is moving how in relationship to the RADAR?

Directly towards or away from the RADAR

20

In stationary RADAR the angular effect is always in whose favor?

The suspect

21

When we adjust a RADARS range we are actually adjusting?

Sensitivity of the RADAR receiver

22

When in doubt which target vehicle the operator tracked what should they do?

Take no enforcement action

23

All RADAR instruments approved for use in NC are required to have ?

audio tracking feature

24

Prior to using the RADAR to corroborate the speed of a vehicle what must the operator form?

An opinion as to the speed of the target vehicle

25

Who may testify with sufficient knowledge and opportunity to observe the speed of a vehicle or the distance within which it could have stopped?

A lay witness

26

Estimating the speed of a vehicle is ________________ ability?

Learned

27

Moving RADAR simply transmit ____ signal(s) out and receives ____ signals back?

one, two

28

When operating RADAR and you approach a vehicle while in the Moving Opposite Direction mode, the proper formula for this is?

Target Speed= Closing Speed - Patrol Speed

TS=CS - PS

29

If the closing speed is 120 and the patrol speed is 50then what is the target vehicle's speed? ( Moving Opposite Direction)

70

30

If the target speed is 75 and the patrol speed is 60, then what is the closing or separation speed? (Moving Direction Opposite)

135

31

Opposite Direction moving RADAR will always have a closing or separation speed ________ than that of the patrol vehicle?

Greater

32

Slight time lags in the Moving Radar's sensing/computing cycle is what is known as?

batching

33

The moving RADAR angular effect, shadowing effect, and batching effect might lead us to think that a suspect is traveling __________ than they really are?

faster

34

The batching effect might happen if the patrol car is substantially changing its __________ while the RADAR speed measurement is being made?

Speed

35

In same direction moving RADAR the formula for target slower mode is?

TS= PS - CS or SS

36

When in Same Direction Moving Mode
(Target Slower)
(Target Faster)
What would be the formula?

Target Slower
TS=PS - CS
Target Faster
TS=PS + SS

37

When in the incorrect mode for same direction moving RADAR, the target speed will change by ____ MPH up or down for each mile per hour change in the patrol vehicle speed?

2

38

Basic goal of all police work?

Protect Lives and Property

39

What has been the target of almost all successful challenges in RADAR cases?

Human Error

40

Radar is only as good as?

The Operator

41

Radar is Only a?

Tool

42

The three elements of driving

The Operator
The Vehicle
Road Surface

43

Average reaction time for a human?

3/4 of a second

44

The braking distance at 40 mph is how many times the distance at 20 mph?

4 (125 feet to stop)

45

The first traffic law in the U.S. was in New Amsterdam (NY) was?

1652 - Riding of horses or driving horse drawn buggies at a gallop

46

The first automobile traffic law was in Hartford Conn. In 1901 prohibiting what?

Speeding is excess of 12 mph in the country and 8 mph within the city limits

47

Three types of speeders laws

Basic Speed Law
Absolute Speed Law
Prim Facie Speed Law

48

North Carolina has two types of speed laws

Basic Speed Law
Absolute Speed Law

49

Basic Speed Law

Speeding greater than is reasonable and prudent under existing conditions

50

Traffic fatalities were reduced _____ in 1974 after the speed limit had been reduced to 55 mph in 1973.

16.8%

51

20-141

Speed Restriction

52

How is a wave length measured?

From the beginning of the peak to the end of the valley

53

Frequency

Number of waves that are transmitted in one second

54

A hertz is the same things as ?

A wave or a cycle

55

X-Band Frequency?

10.525 gigahertz

56

K-Band Frequency?

24.150 gigahertz

57

KA-BAND Frequency

34.700 gigahertz

58

The maximum angle for operating stationary RADAR?

20 degrees

59

When used in RADAR terminology means adjusting the sensitivity?

Range

60

Metal, concrete or other solid objects will _________ the RADAR energy.

reflect

61

Tall grass, leaves will tend to __________ the RADAR energy.

absorb

62

Occurs when target vehicles tend to be traveling close together and the RADAR has a problem picking out targets

Bunching

63

The sound is a translation into sound waves of the Doppler frequency shift experienced by the RADAR beam.

Audio Tracking

64

Results when a phased inversion occurs in the signal and cancels the energy reflected from the target vehicle?

Multi-Path Beam Cancellation

65

The stationary RADAR is moved while a speed measurement is being made.

Scanning

66

Electronic feedback causes erroneous speed measurements when the antenna is aimed at the counting box.

Panning

67

Purposeful attempts to create false or distorted RADAR signals

Jamming

68

Uses its beam to measure two different speeds, the speed of the target vehicle and the speed of the patrol vehicle relative to the ground

Moving RADAR

69

Formulas for Single and Dual Antenna MOVING RADARS

Target Speed=Closing Speed - Patrol Speed (front antenna)

Target Speed= Separation Speed - Patrol Speed (rear antenna)

70

Same Direction Moving RADAR is unable to do what between target faster or slower than the patrol vehicles speed?

Automatically discriminate

71

Radar is not able to keep up with rapid acceleration or deceleration of the patrol vehicle and causes an erroneous speed measurement reading.

Batching

72

The first speed measurements were made with?

Stopwatch

73

Extended when a particular fact or principle is so commonly known as to be a matter of common knowledge and is familiar to most all reasonably well informed persons.

Judicial Notice

74

G.S. 8-50.2

Radar Reliability Act , took effect July 1, 1982

Authority to use particular RADAR units

75

Has the responsibility for establishing minimum standards and levels of training for radar?

The North Carolina Criminal Justice Education and Training Standards

76

Connect the RADAR in the following order

Antenna to Control Box to Remotes to Current.

77

Before a RADAR Speed reading is admissible in trail the officer must testify to these four facts?

1. Held Certification from NCCJETSC on the instrument
2. Operated in accordance with procedures est. by the commission
3. Instrument was approved for use
4. Instrument was calibrated and tested for accuracy with the standards

78

When connecting to the power source the RADAR should be?

Turned off

79

To pass the tuning fork test it must be?

Plus or Minus one mph

80

Tracking History

Perform visual estimate of target vehicle's
Listen to audio tracking
Target speed display should correspond to visual and audio estimate
Verify patrol speed between speedometer and RADAR.

81

When must Calibration with tuning fork test be conducted?

Beginning and end of tour of duty and after each enforcement action

82

Basic Speed Law is found in which statute?

20-141

83

The powers of NCCJETSC are set forth in:

G.S. 17C

84

How much fuel was saved when speed limits were put at 55mph in 1974?

3.6 Billion gallons

85

A wide range of natural and man-made phenomena that affect either transmitted or reflected Radar beams.

Interference

86

When we adjust a RADAR 's range, we are actually adjusting its ________ ?

Sensitivity

87

Testing scores for certification and recertification

Cert. 70%
Recert 75%
Attendance 100%
Motor Skills 100%

88

What does the antenna on a RADAR do?

Shapes, Forms, Transmits, and Receives microwave energy

89

Radio microwave energy will travel indefinitely unless it is?

Reflected (metal, stone,wood,concrete)
Refracted (glass,plastic)
Absorbed (leaves,grass,earth)

90

Radio microwave energy in RADAR travels How fast?

Speed of Light
186,000 miles per second
30 billion centimeters per second

91

Frequency is the number of waves transmitted in how long?

one second

92

Tendency of moving RADAR to display its own speed in target circuitry?

Harmonic Effect

93

K-Band has a wave length of?

1 1/4 centimeters

94

Ka-Band has a wave length of?

4/5 centimeters

95

X-Band has a wave length of?

3 centimeters

96

Under which General Statute does the use of a RADAR corroborate the officer's opinion as to the speed of a vehicle?

G.S. 8-50.2

97

The Doppler Principle is named for the Austrian Physicist?

Christian Johann Doppler

98

The equation for same direction moving RADAR target slower mode rear antenna is?

TS=PS-SS
Target Speed = Patrol Speed - Separation Speed

99

The transmission of a signal at a specific frequency bouncing the signal off a moving object and reflecting the signal at a different frequency?

Radar Concept

100

Equation for moving-opposite lane, rear antenna is?

TS=SS-PS
Target Speed=Separation Speed - Patrol Speed

101

When vehicle's are traveling close together may confuse the RADAR, this is called?

Target Bunching

102

The most frequent traffic accident violations in North Carolina in 1985 and 1986 were:

Speeding

103

Which type of speed law does not exist in North Carolina?

Prima Facie

104

Frequency is the number of waves transmitted in?

One Second

105

The minimum amount of energy a Radar must receive before it will respond to a reflected signal is called?

Radar Sensitivity

106

If the speed limit was raised to 60 mph, traffic fatalities would increase by?

9%

107

At 50mph it takes 188 feet to stop, and at 60mph it takes __________ feet?

272

108

Caused when the signal sent out that is intended to measure the "ground speed" strikes an object that is sending off a stronger signal (such as a large moving truck) than the ground causing an incorrect patrol speed.

Shadowing Effect (moving RADAR only)

109

Police RADAR signals have frequencies of more than _______ waves per second.

10 billion

110

The equation for moving-opposite lane, front antenna is:

TS=CS-PS
Target Speed = Combined Speed - Patrol Speed

111

Is it necessary to identify the vehicle operator, according to state vs Hanson?

No

112

Testing typically begins with a __________ test?

Light Test

113

When operating moving, RADAR, the angle between the Radar and the violators vehicle should be?

As close to 0 degrees as possible

114

How far should tuning forks be held from the antenna?

1-2 inches

115

Common Bands of RADAR signals?

X-Band (10.525)
K-Band (24.150)
Ka-Band (34.700)

116

The RADAR frequency change caused by an object's speed is called the?

Doppler shift

117

Wave Length

3 centimeters in length
The distance between corresponding points on adjacent waves.
(Measured from beginning of the peak to the end of the valley)

118

According to a 1978 survey, which of the road types have the highest incidence of fatal accidents?

Local Streets

119

As a result of the 55mph speed limit, it was estimated that _______ gallons of fuel were saved each year?

3.6 billion

120

Radar check offs and clocks must be completed in what time frame?

2 hours

121

The equation for same direction moving RADAR target slower, front antenna?

TS=PS-CS
Target Speed = Patrol Speed - Closing Speed

122

Produce lower than actual patrol speed measurement, and lead to a higher than true speed calculation?

Shadowing Effect

123

The critical thing to remember is that when in the same direction moving (Target Faster) mode the instrument will?

Always add the patrol speed to the closing speed or (Separation Speed) to compute the Target Speed.
(TS)=PS+(CS) or (SS)
Same Direction "Faster Mode"

124

The elements needed for a same direction moving RADAR tracking history are:

Visual Estimate
Doppler Audio
Target Speed display
Target Speed discrimination
Patrol Speed verification

125

How long do you need to do a tracking history on a vehicle?

Long enough to form an opinion as to the speed of that vehicle