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Flashcards in nct4 v2 edited Deck (180):
1

3 parts of fiber

Coating, Cladding, Core

2

Most common type of fiber used in the cable industry

Single Mode Fiber

3

One Billionth of a meter

nanometer

4

Device that takes the RF and modulates it onto an optical wavelength

Optical Transmitter

5

Optical transmitters use this type of diode

Laser Diode

6

What device detects light and demodulates it to RF

Optical Receiver

7

An optical receiver uses this type of Diode

Photo Diode

8

Devices that are used to compensate for the forward and return loss

Amplifiers

9

What device compensates for the uneven cable loss in coax?

Equalizer

10

It provides a means to monitor levels with out interrupting service

Test Point

11

What device has both a DC & Splitter built into it?

Tap

12

What device is considered to be the customer interface point?

Tap

13

This map is the point where actives are added to the network

Design Map

14

CLI

Cumulative Leakage Index

15

CLI is performed how often?

annually

16

Leakage monitoring must be performed how often?

Every 90 days

17

Leakage logs must be kept on file for how many years?

2

18

AM

Amplitude Modulation

19

PM

Phase Modulation

20

FM

Frequency Modulation

21

The speed at which a wavefront passes through a medium, relative to the speed of light.

Velocity of Prorogation

22

Substance that allows heat or electricity to pass along or through it is called

A Conductor

23

The difference of an electrical field in radiated wave is

Polarity

24

Subatomic particles found in atoms that balance out the positive charge of a proton (within the nucleus) with their negative charge

Electrons

25

_____ is the amount of time it takes an AC waveform to complete one cycle

Period

26

The peak value of an AC waveform is also known as its

amplitude

27

1 complete sine wave =

Cycle

28

number of an AC waveform that occur in 1 second

Frequency

29

A design philosophy where the loss of the cable and other passive devices before an amplifier station equal the gain of the amplifier

Unity Gain

30

The difference in gain between the ends of a band of frequencies

Slope

31

an active device used to increase the level of an input signal. Used in a cable system to compensate for the effect of attenuation caused by coaxial cable and passive devices

Amplifier

32

Small plug-in device used to attenuate signals to the correct operating levels

Pad

33

A device used to reduce signal strength

Attenuator

34

In a cable amplifier it is typically a small, plug in device used to compensate for the fact that coaxial cable attenuation varies as the square root of frequency

Equalizer

35

the difference between in amplitude between the most positive (Peak) and the most negative (Valley) levels of a electrical signal

Peak to Valley

36

An oscillator controlled so that it maintains a constant phase angle relative to a reference signal source

Phase Locked

37

chemical change caused by a reaction to Oxygen such as rust

Oxidation

38

Detects errored bits in the system

Bit error Rate (BER)

39

used for troubleshooting connections with intermittent bit errors occuring over a period of time

Errored Seconds

40

passage of an outside signal into the cable; can result in noise and disruption of the desired signal

Ingress

41

this mode shows you if ingress is within the downstream digital spectrum without turning of service

QAM ingress mode

42

Service quality depends on transmitting signals with the highest carrier to composite noise and the lowest intermodulation distortion. The majority of all transmission errors can be detected by measuring the frequency response of the network is

Sweep

43

This meter is used to measure AC and DC voltages and currents as well as resistance and has a digital display

Digital Multi meter (DMM)

44

is used to find the location/path of underground cables

Cable locator

45

has a transmitter and receiver. it could include the following components a test lead, inductive frame and A-frame.

A locator

46

The resistance of a circuit to alternating current.

Impedance

47

is used to determine the distance of a known fault from a specific location

Time Domain Reflectometer (TDR)

48

Is used to locate: bad or unknown splices, opens, shorts, and kinked cable.

TDR

49

A reflection with the same polarity indicates an

open

50

The distance that cannot be seen by the TDR because its too close to the TDR source

Deadzone

51

two types of TDRs

Waveform and Digital

52

extremely thin flexible thread of pure cladded glass able to carry millions of times the information of a traditional copper wire and do it over greater distances

Optical Fiber

53

A device that generates a light source used in fiber communication

Laser

54

LASER

Light Amplification by Stimulated Emission Radiation

55

Most light generated by lasers for telecomm use exists in the infrared band of 1310nm and 1550nm wavelengths

Infrared Light

56

the distance between two points of like phase in a wave

Wavelength

57

A card made up of material similar to photographic film that changes colors when exposed to light

Photosensitive Card

58

what is the laser standard

ANSI Z-136

59

A method to lock and mark one end of a line in order to allow someone to safely work on the other end

Lockout Tag-out

60

what are the two methods of fiber cleaning

Wet and Dry

61

A battery or generator that provides electrical power to the circuit. For example, batteries and generators

Power Source

62

A conductor such as copper wire

Path

63

Substance that allows heat or electricity to pass along or through it

Conductor

64

Subatomic particles found in atoms that balance out the positive charge of a proton with their negative charge

Electrons

65

the direction of an electrical field in a radiated wave

Polarity

66

An electrical current of which the polarity is periodically reversed.

Alternating Current (AC)

67

the point at which the filament reaches a temperature that causes it to glow

incandescence

68

the relationship between current or voltage and elapsed time

AC Waveform

69

what are the 4 types of AC Waveforms

Sine Wave,
Square Wave,
Quasi-square wave,
Sawtooth Wave

70

one complete sine wave is

Cycle

71

peak value of a waveform

Amplitude

72

states that current is directly proportional to voltage and inversely proportional to resistance

Ohms Law

73

the rate a which work is done or the rate at which energy is used

Power

74

the amount of energy available to move a certain number of electrons from one point to another in an electrical circuit

Voltage

75

to be subjected to the action of an electrical discharge

Shock

76

to kill by electrical shock

Electrocute

77

a connection to the earth or a grounding device

Ground

78

the electricity provided by the local power company

commercial power

79

2 types of line power supplies

standby and non standby

80

reduction of voltage by a transformer

stepped down

81

batteries produce what kind of gas during charging operations

Hydrogen

82

the most accurate and reliable test involves testing the batteries under a load condition

Load Test

83

means of testing the network remotely that saves numerous problems in respect to downtime and customer dissatisfaction

status monitoring

84

A network architecture developed by the cable industry which typically uses fiber optic cables to bring signals to selected areas of the system called Node Service Area, which are usually based on the number of subscribers to be served

Hybrid Fiber Coax(HFC)

85

what are the two wavelengths of fiber do we use

1310 nm and 1550nm

86

a network architecture where nodes, hubs, or headends may be connected with fiber optic cables to provide redundancy or increase services.

Ring

87

What are the advantages of fiber

Greater Bandwith and can travel greater distances without Amplification

88

what are the two types of Fiber

Single mode and Multi mode(we use single mode)

89

the distance between two points of like phase in a wave

wavelength

90

compares the speed of light through a material to the speed of light through a vacuum

Index of Refraction

91

what is the primary loss in fiber called

Scattering

92

separates(and recombines) the forward and reverse signals from the coax cable so they can be routed to and from the appropriate components within the amplifier station

Diplex filter

93

separates or combines the AC currents two parts-( AC power and RF broadband signals)

Power Diplex

94

attenuates the signal in order to bring it to within the acceptable range of the amplifier

Pad

95

compensates for the unequal attenuation properties of the coaxial cable. usually selected to produce flat broadband signals to the input of the first stage of Amplification

Equalizer

96

provides a means of monitoring the various inputs and outputs without interrupting service

Test Points (TP)

97

A design philosophy where the loss of the cable and other passive devices before an amplifier station

Unity Gain

98

similar to a street map and includes features like lakes and rivers, streets, and boundaries

Base Map

99

Displays streets with poles and pedestals locations and includes the span length or footage between these items

Strand Map

100

Shows the locations of electronic equipment. including headend and any hubs,amplifiers, power, supplies, and taps.

Design Map

101

a thin wire wrapped around the fiber and coaxial cables to secure them to the strand

Lashing wire

102

is the tension caused by the mass of cable on the reel and reel brakes.

tail loading

103

is a connection to earth or a conductor serving earth potential and can be intentional or accidental

Ground

104

is the interconnection through good conductors of the cable plant with power and phone systems to eliminate potential voltage differences

Bond

105

is a pipe usually made of PVC and used to house cable and protect it from dirt, moisture, and outside forces.

conduit

106

a high visibility tape usually used when burying fiber optic cable, buried directly above the cable point out the existence of the cable to anyone digging in that location

Warning Tape

107

the US government agency established in 1934 to regulate electronic communications

Federal Communications Commission(FCC)

108

In 1990, the FCC required that system perform s CLI test ____

Annually

109

Leakage is emitted RF energy and is called

Egress

110

Noise is received energy and is called

Ingress

111

LTE

Long Term Evolution

112

Leakage monitoring must be done

Quarterly

113

Leakage logs must be kept on file for

2yrs

114

CW

continuous wave

115

the FCC requires that __ of the plant be tested for CLI. The comcast standard is _____

75% and 100%

116

Comcast troubleshooting steps

Identify, Isolate, Repair, Verify

117

Divide and conquer does what

reduces repair time.

118

is defined as two or more customers without service or with impaired service, due to the same root cause

outage

119

is a signals inability to be transmitted from one cable or device to another cable or device and measured in dB

Isolation

120

is the interface location in a cable system where a fiber enters a neighborhood and the optical signal is converted into an electrical signal to connect to coaxial cables serving individual homes.

Node

121

is an amplifier used to transport signals to longer distances

trunk amplifier

122

are high gain amplifiers and are operated so that the output levels are higher as well

Line extenders

123

to energize or power the equipment( nodes amplifiers and other active devices in the rf portion of the network). usually includes checks for continuity, shorts, and signal flow.

activation

124

the number of times the base is multiplied by itself

exponent

125

is a number where the base is 10

power of 10

126

an absolute level that describes the amount of signal at a specific location in the system.

dBmV

127

a discontinuous signal whose various states are discrete intervals apart

digital signal

128

are a continuous signal or carrier that varies in amplitude or frequency

analog signals

129

this term is short for binary digit. refers to an electrical impulse representing a zero or a one. the smallest unit of measurement a computer can handle

bit

130

a set of bits that represent a single character. usually there are eight bits in a

Byte

131

is the measuring of the analog signal at specific intervals

Sampling

132

is the assigning of a specific value to each of the samples

Quantization

133

is the process by which these values are converted into a data or bit stream

Encoding

134

can interfere with an analog signal and reduce its clarity

thermal or interfering noise

135

are regenerated rather than amplified

Digital bits

136

is the means of superimposing sound on an RF carrier

AM

137

is the means of superimposing sound on an RF carrier of a particular frequency

FM

138

3 different types of modulation in analog

Amplitude(AM),Frequency(FM), and Phase(PM)

139

defined as the position on a waveform cycle at a specific point in time. on cycle is defined as 360 degrees of phase

Phase

140

the two most common digital modulation schemes that use a combination of changes are

QPSK and QAM

141

often caused by poorly made or corroded connectors ,it actually changes the shape of the RF wave from(disimilar metals)

common path distortion (CPD)

142

a chemical change caused by a reaction to oxygen, such as rust

Oxidation

143

is caused by random electron activity of the atoms that make up the conductor, resistor, or any part of the passive circuit in question at any temperature above absolute zero

thermal noise

144

undesired change in the waveform of a signal

distortions

145

the second harmonic products of any two channels are typically 6dB below the level of the sum and difference products

Discrete second order

146

an international telecommunications standard that permits the addition of high speed data transfer to an existing CATV system

DOCSIS

147

generates light in the transmitter

Laser Diode

148

is a family of standards for compressing decompressing A/V in a digital format

MPEG

149

advantages of MPEG are

remove redundant info without losing quality while saving bandwith

150

MPEG1

video CD

151

MPEG2

HDTV/DVD

152

MPEG4

streaming video

153

has all the spatial info

I picture

154

use both past and subsequent pictures

B picture

155

is calculated by comparing previous and successive picture

P picture

156

a cable version of CDMA , a cell phone technology that allows many users to access the network at the same time

SCDMA

157

provides the ability to control latency

QOS

158

how many channels can u bond with docsis 3.0

4 or 8 down 4 up

159

number of timeouts caused by the cmts not receiving a response within aspecified time from the cmts to a ranging request. upstream errors

T3

160

number of timeouts caused by the modem not receiving a response within a specified time from the cmts to a periodic maintenance request. downstream errors

T4

161

the operational settings for the cable modem

Boot file

162

a series of Reed -Solomon symbols forms the codeword. it s a series of values that conforms to a known pattern.

codewords

163

when there are more than___ errored symbols in a codeword the entire codeword is errored

3

164

technologies that allow cable modems to share the upstream carriers in the hfc network with multiple devices like cable modems, emtas, and set top boxes

TDMA and SCDMA

165

assigns time slots for when modems can speak. configured in the CMTS

TDMA

166

instead of a time slot, the modem gets a code for all the data it is sending

SCDMA

167

is a set of rules that govern how devices transport data

Protocol

168

allows interoperability of devices from different vendors

protocols

169

is a way to tell the sending server that not all packets got to their destination, and please resend them.

Transmission control protocol/ internet protocol (TCP/IP)

170

used to transport voice and video media

Real Time Transport Protocol (RTP)

171

unlike tcp/ip it has no error correction

Universal Datagram Protocol (UDP)

172

UTP

unshielded twisted pair

173

has a field of 32 bits and dotted decimal

ipv4

174

written in colon hexidecimal format and uses numbers and letters

ipv6

175

can be configured for ipv4only or ipv6only

single stacked device

176

can be configured fro both ipv4 or 6

dual stacked device

177

rules for writing ipv6 addresses

1) omit leading zeros, meaning zeros at the beginning of each set of four characters. 2) replace consecutive all zero chunks within an address by using a double colon

178

What component is known as the brain of the cable system?

Headend

179

What are the signals that are used to pass channels to the customer?

Analog and Digital

180

Any device which requires electricity to perform its function?

Active Device