RADAR Flashcards
(126 cards)
1
Q
The word “RADAR” is an acronym. What do the letters stand for?
A
Radio, Detection and Ranging
2
Q
The Radars transmitted signal will travel how far?
A
Infinitely until absorbed,reflected or refracted
3
Q
Radio Energy always travels how fast?
A
186,000 miles per second
Speed of Light
4
Q
At what speed does both transmitted and received RADAR signals travel?
A
Constant Speed
4
Q
At what speed does both transmitted and received RADAR signals travel?
A
Constant
5
Q
No person should drive a vehicle on a highway at a speed greater than is reasonable and prudent under existing condition is known as?
A
Basic Speed Law
6
Q
Prime Facie means?
A
“At first sight”
7
Q
Does NC have a prime facie law?
A
No, it has the absolute speed law
8
Q
What is the absolute speed law?
A
drive faster than a specific numeric speed
9
Q
What elements make up the speed offense?
A
Driver Identification
Location
Speed
Conditions
10
Q
With the oil embargo of 1973, Congress imposed what maximum speed in 1974?
A
55 mph
11
Q
Frequency of a K-Band RADAR signal?
A
24.150 gigahertz
12
Q
Frequency of a Ka-Band RADAR signal?
A
34.700 gigahertz
13
Q
Ka-Band RADAR signals has a wave length of about?
A
4/5 centimeters
14
Q
X-Band RADAR signal has a wave length of about?
A
3 centimeters
15
Q
The RADAR signal’s speed stays the same but its _________ and ___________ both change?
A
wave length and frequency
16
Q
Relative motion will only occur when?
A
The RADAR stands still and the object moves or
The object stands still and the RADAR moves
17
Q
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?
A
Relative Motion
18
Q
What determines how much higher or lower the reflected signal’s frequency will be?
A
speed of the relative motion
19
Q
In stationary RADAR the true speed of the object can only be measured if the object is moving how in relationship to the RADAR?
A
Directly towards or away from the RADAR
20
Q
In stationary RADAR the angular effect is always in whose favor?
A
The suspect
21
Q
When we adjust a RADARS range we are actually adjusting?
A
Sensitivity of the RADAR receiver
22
Q
When in doubt which target vehicle the operator tracked what should they do?
A
Take no enforcement action
23
Q
All RADAR instruments approved for use in NC are required to have ?
A
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
