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1

The topology where signals originate in the headend andare transmitted long distances via trunk cables

Tree and Branch

2

A network architecture that typically uses fiber optic cables to bring signals to selected areas of the system called nodes

Hybrid Fiber-Coax (HFC)

3

Bi-annual tests, performed in the headend and at a number of end-of-line location

FCC Proof-of-Performance

4

The cumulative effect of return path distortions they are added to the signal at various locations in the coaxial portion of the network.

Funnel Effect

5

Specifications standards approved by the FCC in 1953for commercial analog color TV broadcasting.

National Television Standards Committee (NTSC)

6

a portion of the electromagnetic spectrum whose frequencies are well suited for transmitting and receiving Telecommunications signals through the air.

Radio Frequency (RF) Spectrum

7

Signals that flow downstream, from the headend to the network.

Forwards (Downstream) Signals

8

Signals that flow in the upstream direction, from customer to headend

Revers (upstream) Signals

9

Device that separates or combines based on frequency.

Diplex Filter

10

typical cutoff frequency for a sub-split diplex filter

About 50 MHz

11

The three major concerns/ limitations of the tree andbranch architecture are:

BandwidthImpairmentsDependency on Power

12

The lowest possible power level determined by the thermal noise generated within the electrical componentsbeing tested

Noise Floor

13

The highest power level (amplitude) reached by a carrier

Peak

14

A clustering of beats 1.25 MHz above the visual carriers in a CATV network

Composite Second Order (CSO)

15

A form of interference or noise resulting from the mixingof all of the various carriers in a CATV network

Composite Triple Beat (CTB)

16

Two major types of distortions that are typically associated with CATV

Composite Second Order (CSO) and Composite Triple Beat (CTB)

17

The 6 benefits of implementing fiber optics in broadband networks

Enhances Picture QualityIncreased ReliabilityDecreased cost of system maintenanceCost effective system bandwidth upgradesCost means of system upgrade requiring a complete change our of electronicsSmall segmented areas allow greater return path functionality

18

Having or relating to a frequency below the audibility range of the human ear.

Infrasonic

19

A stream of atomic nuclei that enter the earth’s atmosphere from outer space at speeds approaching that of light

Cosmic Rays

20

Frequency range of satellite systems

4GHz to 13GHz

21

The wavelengths most commonly used by the CATVindustry

1310nm and 1550nm

22

The type of fiber optic cable that the broadband industry uses

Single Mode Fiber

23

The process of combining multiple carriers onto a single medium

Multiplexing

24

Width of the Fiber optic core

8-10um

25

Width of the fiber optic cladding

125um

26

Width of the fiber optic coating

250um

27

Combines multiple optical signals in order to amplify them as a group and transported over a single fiber

Wave Division Multiplexing (WDM)

28

Allows multiple wavelengths above and below a centerwavelength to be carried on a single optical fiber.

Dense Wave Division Multiplexing (DWDM)

29

Three parts of the optical link

Fiber Optic CableTransmitter (Laser)Receiver (Node)

30

Individual fibers are bundled and then placed into these to reduce the possibility of damage

Buffer Tubes

31

This diode changes the RF signals to pulsesof light and then transmits them onto an optical fiber

Semiconductor Laser Diode

32

The Three types of optical transmitters that are typically used in broadband HFC Network

Fabry-Perot (F-P)Distributed Feedback (DFB)Yttrium-Aluminum-Garnet (YAG)

33

YAG

Yttrium-Aluminum-Garnet

34

DFB

Distributed Feedback

35

F-P

Fabry-Perot

36

A spare fiber installed during the construction of the network that was reserved for future use.

Dark Fiber

37

Three advantages of trunk reduction

Shorter CascadesFewer/smaller outages due to segmenting the system into smaller areasImproved picture Quality

38

FTTF

Fiber to the Feeder

39

Advantages of FTTF

Shorter CascadesFewer/smaller outages due to segmenting the system intosmaller areas.Increased Bandwidth

40

FTTC

Fiber to the Curb

41

PON

Passive Optical Network

42

Consists of a transmitter at the Headend and a receiver near the subscriber. Requires a power supply near the node but all other actives have been removed

FTTC PON

43

4 advantages of FTTC

No active devices after nodeNo CascadeFewer/smaller outages due to segmenting the system intovery small areasIncreased Bandwidth

44

A fiber-based network which uses passive splitters todeliver signals to multiple locations

Passive Optical Network (PON)

45

FTTH

Fiber to the Home

46

6 advantages of FTTH

Passive networkSingle fiber is dedicated to each subscriberFeatures local battery backup, no large remote power supplies are required.No exterior active devicesNo CascadesIncreased Bandwidth

47

This will ALWAYS be considered the "Backbone" in an HFC Network

The Fiber Network

48

A high-speed line or series of connections that forms a major pathway within a network

Backbone

49

The duplication of certain pieces and/or portions of thenetwork.

Redundancy

50

Comcast's goal for network reliability

"four-nines" or 99.99%

51

A network architecture where nodes, hubs, or headendsmay be connected with fiber optic cables to provideredundancy or increase services

Ring Architecture

52

Builds upon ring technology by adding a second (redundant) ring connecting the nodes to the headend. The second ring typically takes a different path

Ring within a Ring

53

A facility between the headend and the customer that performs many of the functions of a headend

Hubsite

54

Similar in function to a hubsite, but serving fewer customers

Optical Transition Node (OTN)

55

Usually a passive device such as a splitter or directional coupler used to combine radio frequency signals from one source with those from another

RF Combiner

56

Usually a passive device that divides a signal into two equal paths. It may be found on trunk, feeder, or drop cable.

RF Splitter

57

Device used to combine the channels for entry onto the cable or fiber optic transmitter

Headend Combiner

58

The difference, in dB, of a signal level, injected into one output port, and the measured level of that same signal on another output port, with the input port properly terminated.

Port-to-port isolation

59

Obtained by measuring the attenuation between the two output ports (A and B) when the common port (input port) is terminated in the correct value of impedance. An RF generator signal is applied to port A and an RF voltmeter reading is taken at Port B.

Isolation

60

Provision for connection to a device such as a tap, splitter, set-top box or computer

Port

61

Used to combine all of the signals to be carried over the cable system into a single medium (cable) for routing to the laser transmitters that are feeding the optical nodes in the system

Headend Combining Network

62

A measurement of the reflected signal compared to that of the incident signal

Return Loss

63

Device used to divide or combine light carriers on fiber optic cables.

Optical Splitter

64

A discontinuous signal whose various states are discrete intervals apart.

Digital Signal

65

Device used to convert an analog signal to a digital signal.

Digitizer

66

takes an amplitude measurement of the waveform at fixed intervals of time, and converts them to a binary number

Digitizer

67

The smallest unit of computerized data. Bits are defined as single characters of 0 or 1. Bandwidth is usually measured in bits-persecond.

Binary Digit (Bit)

68

A set of Bits that represent a single character. Usually there are 8 Bits in a Byte, sometimes more, depending on how the measurement is being made.

Byte

69

The number of changed states that can occur per second.

Baud

70

The value of "On" in a binary system

"1"

71

The value of "Off" in a Binary system

"0"

72

How many bits are in a "Nibble"?

4

73

In ASCII #5 alphabet, how man bits are in a byte?

7

74

If start and stop bits are included with Asynchronous Communications, then how many bits are in a byte?

10

75

ADC

Analog to Digital Conversion

76

DAC

Digital to Analog Conversion

77

A continuously varying signal with an unlimited number of possible values of amplitude and frequency.

Analog Signal

78

a non-continuous signal or carrier that changes its output in discreetly timed steps of voltage level and/or phase that can represent numerical values or other information

Digital Transmission

79

3 steps of basic ADC

SamplingQuantizationEncoding

80

The "Measuring" of the analog signal at specific intervals.

Sampling

81

The assigning of a specific value to each of the samples

Quantization

82

The process by which Quantized values are converted into a data or bit stream

Encoding

83

ASK

Amplitude Shift Keying

84

FSK

Frequency Shift Keying

85

QPSK

Quadrature Phase Shift Keying

86

QAM

Quadrature Amplitude Modulation

87

The process of varying the amplitude, frequency, or phase of a carrier to be in step with the instantaneous value of the modulating waveform

Modulation

88

Data transmission scheme wherein the carrier is shifted in amplitude

Amplitude Shift Keying (ASK)

89

The carrier frequency is shifted to represent the difference between a one and a zero

Frequency Shift Keying (FSK)

90

The position on a waveform cycle at a specific point in time. One cycle is defined as 360 degrees of this

Phase

91

Digital modulation scheme wherein the carrier is shifted in 90 degree steps. There are four possible phase states and the magnitude is constant.

Quadrature Phase Shift Keying (QPSK)

92

BPSK

BiPhase Shift Keying

93

In QPSK, what does "I" stand for?

In-Phase

94

In QPSK, what does "Q" Stand for?

Quadrature - shifted 90* or one quarter of a cycle

95

A graphic depiction of the four phase states of a Quadrature Phase Shift Key signal.

Constellation Diagram

96

What is the bandwidth of QPSK in a 6MHz bandwidth?

10 Mb/s

97

Digital modulation scheme that changes the phase and the amplitude.

Quadrature Amplitude Modulation (QAM)

98

a digital transmission technology that splits the frequency band into a number of channels. The channels are each assigned a specific time slot, so that several transmissions can share a single channel without interfering with one another

Time Division Multiple Access (TDMA)

99

The digital equivalent to Signal-to-Noise

Modulation Error Ratio (MER)

100

A joined or connected group of devices

Network

101

A network of computers linked by cable within a building or office complex.

Local Area Network (LAN)

102

A network of multiple locations linked by cable withina city or campus

Metropolitan Area Network (MAN)

103

A network typically bigger than a city or metropolitan area.

Wide Area Network (WAN)

104

A data network connects each of its endpoints to the network with a single link. A central device (hub) is used to aggregate and distribute data traffic to all endpoints and/or other central points in what’s referred to as a clustered star.

Star

105

Consists of several star networks that have been linked together

Clustered Star

106

Topology where workstations are connected to the network through a common path

Bus

107

A topology in which a data frame is passed around. As it arrives at an endpoint, the endpoint can either pass it along to the next endpoint or attach information to be sent to a destination

Token Ring

108

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

Ring

109

A method of data transmission that allows characters to be sent at irregular intervals by preceding each character with a 0 and by ending each character with a 1. This is referred to as start (0) and stop bits (1). It is the method, which most PCs use to communicate with each other and mainframes

Asynchronous Transmission

110

An extra bit added to help check if the data that isbeing transferred is correct

Parity Bit

111

The condition that occurs when two events happen in a specific time relationship with each other and both are under control of a master clock. Characters are spaced by time, not by start and stop bits.

Synchronous Transmission

112

Synchronizing bits used in synchronous transmission to maintain synchronization between transmitter and receiver.

Sync Bits

113

SNMP

Simple Network Management Protocol (SNMP)

114

NE

Network Elements

115

MIB

Management Information Base

116

A unique number assigned to a piece of equipmentused for identification purposes.

Media Access Control Address (MAC)

117

UTP

Unshielded Twisted Pair

118

signaling rate of 10BaseT

10 Mb/s

119

Signaling rate of 100BaseT

100 Mb/s

120

The designation for Ethernet over fiber optic cable, primarily for point-topoint links

10Base-F

121

Ethernet resides in what layers of the OSI model?

The 2 lowest levels (layers)

122

This device works as a multiport signal repeater, broadcasting an incoming signal to all other ports on an ethernet network

Ethernet Hub

123

The four-part numeric address that is assigned to a computer or an account as an identification tool

Internet Protocol Address (IP)

124

IEEE MAC Protocol for Hybrid Fiber-Coax Networks; standard for data communicatons over a cable network

802.14

125

The Four original partners of MCNS (Multimedia Cable Network Partners Ltd.)

Comcast, Cox, TCI and Time Warner

126

The three companies that joined MCNS in late 1996

Media One, Rogers Cablevision and CableLabs

127

DOCSIS

Data Over Cable Service Interface Specification

128

When was DOCSIS 1.0 released? (Month and Year)

March 1997

129

The Leading standard for cable modems

DOCSIS

130

Four devices that must be added to a system to offer high-speed internet

CMTS (Cable Modem Termination System)CM (Cable Modem)ServersNoise Filters

131

A unit consisting of various hardware and software entities that acts as the hand-off point between the RF based HFC network and other networks such as theInternet and the PSTN.

CMTS (Cable Modem Termination System)

132

Used to terminate, manage and translate high-speed Internet sessions between cable modems in a LAN and other devices in a WAN.

CMTS (Cable Modem Termination System)

133

The collection of computers accessed through the Internet. Uses a hypertext based system for finding andaccessing its resources.

WWW (World Wide Web)

134

Four Items that a CMTS manages

Time SlotsContention SlotsModem DataTransmit Levels

135

Each cable modem is assigned one of these by the CMTS and only one modem is allowed to transmit during this.

Time Slot

136

These slots are usually used for short data transmissions such as a request for an additional number of reserved time slots

Contention Slots

137

The signal level that the CMTS wants to "See"

0dBmV

138

A PC on a LAN from which information or applications are requested.

Client/Server

139

A computer circuit board (card) installed in a computer so that the computer can be connected to a network. Provide a dedicated, full-time connection to a network.

NIC (Network Interface Card)

140

Why is it called a cable "Modem"?

When they transmit data they "MOdulate" the data onto a carrier, then receive data and "DEModulate" it from the carrier and send it on to the computer

141

Four of the most common servers found in a braodband network

DHCPTODTFTPProxy

142

This server sets up the MAC and IP addresses for the cable modem.

DHCP Server(Dynamic Host Configuration Protocol)

143

This server sets up a common clock between the CM and the CMTS

TOD Server(Time of Day)

144

This server allows non-protected file transfers, such as aconfiguration file for a modem.

TFTP Server(Trivial File Transfer Protocol)

145

These servers store commonly used (or contractually stored) data. A network may have a series of these servers located in different places.

Proxy Server

146

The two types of noise filters

High Pass FilterNotch Filter

147

These types of filters only allow signals above 50MHz to pass through the filter

High Pass Filter

148

In addition to letting everything above 50 MHz to pass, this filter allows a small spectrum below 50 MHz to pass

Notch Filter

149

The process of setting up the connection between theCMTS and the cable modem, where transmit levels andfrequency are determined.

Ranged

150

A switch or collection of switches connecting multiple networks

POP (Point of Presence)

151

The point of access into theInternet.

NAP(Network Access Point)

152

The company who provides access to the Internet and the World Wide Web, who usually also provides corefeatures such as e-mail.

ISPInternet Service Provider

153

The local, long-distance and internationalphone system in use today

PSTN(Public Switched Telephone Network)

154

This device in the Headend controls the operation of CDV.

HDT(Host Digital Terminal)

155

Three major components of the Host Digital Terminal

Access Bandwidth Manager ShelfModem ShelfSpectrum Manager Shelf

156

This Shelf provides the connection between the Network Interface Unit (NIU) and the switch, or more simply, the connection between the HDT and the LEC

ABM(Access Bandwidth Manager)

157

The point of demarcation between the network and the customer. It contains the modem necessary for telephony over a cable network.

NIU(Network Interface Device)

158

The device that opens or breaks the circuit path in a telephone call. This device looks at the incoming data to determine where the data should get routed.

Switch

159

The local phone company is also known as what?

LEC(Local Exchange Carrier

160

Shelf on the HDT (Host Digital Terminal) that converts the digital telephone signals into digital signals that are then modulated onto an RF carrier to be transmitted over the HFC Network.

Modem Shelf

161

This shelf on the HDT (Host Digital Terminal) monitors the RF spectrum allocated for telephone services over the HFC network. If problems are detected, it can switch the data transmission (telephone call) to another frequency.

Spectrum Manager

162

How many subscriber telephone lines can an NIU Handle?

4

163

LPSU

Local Power Supply Unit

164

The process of setting up the connection between the HDT and the NIU, where transmit levels and frequency are determined.

Marshalled

165

Modulating technique that interweaves multiple conversations, based on time.

TDMA(Time Division Multiple Access)

166

The number of the person that youare trying to call.

Terminating Number

167

The phone company of the person you are trying to call.

Terminating LEC

168

The “local” phone office where the subscriber’s lines are connected to the switching equipment.

Central Office

169

What is "7" equal to in binary?

0111

170

64 QAM has how many phase angles?

52

171

16 QAM has how many phase angles?

10

172

The distance between two points of like phasein a wave.

Wavelength

173

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

Photosensitive Card

174

ANSI Laser standard that separates lasers into various classes that take into consideration the operating wavelength, output power level and whether the laser operates as a continuous or pulsed light output

Z-136

175

Four nines works out to how many minutes of down time per month?

4.5 minutes

176

loss of service to ourcustomers due to a fault in thedelivery network.

Outage

177

Minimum telephone service to assure a contact in case of an emergency.

Lifeline

178

FCC Standards CFR 47, Part 76.605(a)(1-12)

Proof-of-performance (POP) test

179

A continuous wave (CW) frequency onto which information is modulated for transport.

Carrier Frequency

180

Maximum Bandwidth of 256QAM

42.88Mbps

181

How long must POP tests be kept at the local office?

minimum of 5 years

182

how many test points are required for 1,000 to 12,500 customers?

6

183

How many test points are required for each additional 12,500 customers?

1

184

Channel requirements for POP testing (amount)

4 channels plus one additional channel for every 100 MHz.

185

In a cable system with an upper frequency at 750 MHz, how many test channels must be used?

11 Channels

186

All channels must be tested during these 3 tests.

Video Carrier Level, Audio Carrier Level, Video Carrier Level Stability Test

187

Only one Channel needs to be tested during this non-frequency specific test

Hum Modulation

188

How many digital channels must be tested on an all digital system with an upper frequency of 862MHz?

0, digital channels are not included and are not tested.

189

The amount of channels during these tests are based solely on the highest operating frequency

Video-Audio Carrier Frequency SeparationIn-Channel ResponseCarrier to NoiseCoherent Disturbances Tests

190

This test must be performed twice a year, once during the coldest months and again during the warmest (Jan-Feb and Jul-Aug respectively)

Video Carrier Level Stability (24-hour) test

191

This POP test must be performed every three years

Color Performance test

192

A circuit that automaticallyadjusts the gain of an amplifier sothat the output signal levels stayconstant despite varying inputlevels.

Automatic Gain Control (AGC)

193

a spectrumanalyzer feature that allows theuser to make otherwise intrusiveFCC POP tests in a non-intrusivemanner.

Gated Testing

194

When planning POP tests, these four things need to be considered

Test timesChannels and programming affected by testingTest lengthsAbility to perform non-intrusive gated testing

195

This test is usually performed by a Headend tech rather than a System Tech

Color Performance

196

What would a Discrepancy statement include?

Explain all possible misinterpreted fails, such as test point relocation, added channels, encoding issues and so on.

197

POP measurements are to be taken at what location?

Input to the subscriber terminal

198

EIA

Electronic Industry Association

199

What must an operator do in order to pass the receivability test?

Submit documentation showing that their channel lineup conforms to the EIA Channel allocation plan

200

What does the Audio Carrier Frequency Test ensure

That the audio carrier frequency for each channel must be 4.5MHz above the video carrier frequency, +/- 5kHz

201

Where is the Audio Carrier Frequency test performed at?

The Headend as well as the field test points

202

How many times a year is the Audio Carrier Frequency test performed?

Twice annually

203

What type of set-top box can alter the Audio Carrier Frequency?

Baseband set-top boxes (as opposed to non-baseband)

204

What six measurements are taken during the 24-hour test?

Minimum Visual Signal LevelVisual Signal changeAdjacent Visual SignalAny Other Visual Signal in BandwidthVisual Carrier LevelAudio Carrier Level

205

The six measurements that are taken during the 24-hour test are performed on what channels?

All NTSC Channels at each test point location

206

What is the Minimum Visual Signal Level allowed at the end of a 30-meter (100') cable drop that is connected to the subscriber tap?

1.41mV across an internal impedance of 75 ohms (+3dBmV(CT 5-3-22)

207

The square root of the sum ofthe squares of the amplitudes ofindividual components of afunction, such as the frequencycomponents of a signal.

Root Mean Square (RMS)

208

Maximum variation of each channel within any six-month period at the end of a 30-meter drop cable

8dB

209

Adjacent Visual Signal deviation of the visual signal level of any visual carrier within a 6MHz nominal frequency separation

3dB

210

What is the maximum "spread" or deviation among ALL channel levels in a 300MHz cable system and what is the incremental increase

10dB1db per 100MHz

211

At what level must the aural signal be maintained in association with the visual signal level?

between 10dB and 17dB below the visual signal level

212

At what level must the aural signal be maintained in association with the visual signal level on a baseband converter.

between 6.5dB and 17dB below the visual signal level.

213

In a 24-hour test, how many times must the signal level be checked?

four times

214

What are the time intervals of the 24-hour test?

5 to 7 hours

215

at what frequency is the In-Channel Response test performed?

.75MHz to 5Mhz above the lower frequency boundary of the cable channel under test

216

What is the FCC In-Channel Response requirement?

+/-2dB or 4dB peak-to-valley

217

To perform this test, a signal must be inserted on the channel, either by the headend technician or by other means

In-Channel Response Test

218

FCC Requirement for C/N

43dB at each test point

219

What are the three type of coherent disturbances?

Composite Second Order (CSO)Composite Triple Beat (CTB)Other interfering signals (i.e. Ingress)

220

What is the FCC requirement for Coherent Disturbances?

51dB below the desired carrier level for STD plans and 47dB in IRC and HRC systems

221

The goal of this test is to find the worst beat or interfering signal, regardless of it's type

Coherent Disturbances Test

222

FCC requirement for isolation

18dB

223

Because the FCC allows you to submit manufacturers specifications to prove compliance, you rarely need to perform this test:

Terminal Isolation Test

224

FCC requirement for Hum Modulation

less that 3% of the video carrier level.

225

Where is the Hum Modulation test done?

the end of a 30m or 100' drop

226

how many channels is the Hum Modulation test performed on?

One channel per test point

227

How many channels is the Coherent Disturbance test performed on?

Dependent on highest frequency

228

What are the three Color Performance tests?

Chrominance to Luminance Delay InequalityDifferential GainDifferential Phase

229

FCC Spec for Chrominance to Luminance Delay test

Within 170 nanoseconds

230

FCC Spec for Differential Gain

Within +/-20%

231

FCC Spec for Differential Phase

Within +/-10 degrees

232

Who usually performs the color performance tests?

The Headend Technician

233

How many channels are recommended to be tested during the Color Performance test?

All NTSC or similar channels

234

How often are the Color Performance Test performed?

once every three years

235

Allowable signal leakage level below 54MHz

Up to 15uV/m @ 30m

236

Allowable signal leakage level between 54MHz and 216 MHz

up to 20uV/m @ 3m

237

Allowable signal leakage above 216MHz

up to 15uV/m @30m

238

The two types of leakage monitoring frequency.

Continuous MonitoringQuarterly Monitoring

239

Two types of annual leakage monitoring methods

Ground BasedFlyover

240

What is the minimum cable strand sample allowed during a ground based leakage measurement?

75%

241

What leaks are included in the CLI calculation?

All leaks 50uV or greater

242

what is the elevation that a flyover is completed at? (in meters)

450m(1476')

243

Two requirements for monitoring of plant with a handheld signal leakage detector

-Must be properly calibrated to detect a leak of 20uV/m or greater @ 3m-Perform all measurements with a horizontally polarized dipole antenna, preferably located no more than 3m from the leak and 3m from the ground

244

What does a Spectrum Analyzer Display?

information in the amplitude (vertical) vs. frequency (horizontal) domain over the entire spectrum or portions of it.

245

comparable in certain respects, typically in a way that makes clearer the nature of the things compared.

Analogous

246

This filter has a bell-curved "shape," which it applies to all energy passing through it.

Resolution Bandwidth Filter (RBW)

247

This is a low-pass filter at the analyzer detector's output. This filter takes the RF energy associated with the video modulation on the carrier that has already passed through the RBW filter and the detector and smoothes it out

Video Bandwidth Filter (VBW)(CT 5-3-39)

248

The signal to an analyzer is injected here

RF Input

249

Used when accessing analyzer's gated mode, such as in the C/N POP test

TV Input Connector

250

The main setting and adjustment keys for the analyzer functions and the display. These keys are most often used in the analyzer's manual testing modes

Function Keys

251

Additional keys whose action changes depending on the selected analyzer mode or function. Most often used in the analyzer's automated testing modes

Softkeys

252

The principal keys useed in the analyzer's manual modes of operation. They represent the three most basic functions of any spectrum analyzer

Frequency, Span and Amplitude keys

253

Adjusts the value or amount for the selected function or measurement

Adjustment Knob

254

Adjust value or amount in incremental steps for the selected function or measurement

Step Key

255

Allows direct input of a specific value or amount for the selected function or measurement

Numeric Keypad

256

Sets the type of measurement unit, such as kHz or MHz, for the selected function or measurement

Measurement units' keys

257

Marker function and trace control keys

Access marker functions and set trace control functions such as display line, RBW and VBW

258

Sets analyzer modes, presets and stores or recalls analyzer trace

Mode select Key

259

Maximum input power of HP 8591C

+72dBmV

260

Maximum input power of Tektronix 2715

+69dBmV

261

This must be used when high input levels are required to the analyzer to avoid input overload

preselector

262

For the greatest accuracy, how should the carrier peak be adjusted?

To the analyzer's reference level (top of the display)

263

Three tests that can use gated mode on the HP 8591C

Carrier to NoiseCoherent Disturbances (CSO measurement only)In-Channel Response

264

states that in order to obtain an accurate recreation of a signal, it must be sampled at a rate of at least twice the highest frequency

Nyquist's Rule

265

What is the minimum and maximum signal level of a 256 QAM channel?

-8dBmV to +10dBmV

266

What is the minimum MER of a 256 QAM channel?

33dB

267

What is the minimum Pre BER of a 256 QAM Channel?

less than 1.0E-07

268

What is the minimum Post BER of a 256 QAM Channel?

less than 1.0E-09

269

What is the maximum DOCSIS TX level?

Less than or equal to 53dBmV

270

In a constellation diagram, this is when the outer dots are pulled to the center while the ones nearer the center are unaffected

Compression

271

In a Constellation Diagram, this is where the dots appear as an arc as you look toward the outer edge of the display

Phase Noise

272

In a Constellation diagram, this will cause the dots in the clusters to appear to form circles

Coherent interference

273

In this distortion, the distance between the clusters on the I axis are greater, or lesser, than that of the Q axis

I Q imbalance

274

Coherent interference can be caused by one of four things, these are:

CTB, CSO, Beats and Ingress

275

Improperly installed connectors and jumpers, contamination of the connector, improper cable routing or a localized failure fall under this optical failure category:

Patch Panel Related

276

Over or under-driving the optical transmitter falls under this optical failure category

System Related

277

Due to causes such as improper bending radius or a clamped cable falls under this optical failure category

Installation Related

278

Normally due to construction and work related activities, it can also be damaged by improper installation techniques, gunshots, falling branches and automobile crashes. These types of failure incidents fall under this fiber optic failure category:

Construction Related

279

Good isolation in the headend reduces...

Adjacent Channel Interference

280

Continuously varying signals

Analog Signals

281

A mathematical representation of an analog signal

Digital Signal

282

Why can signals travel great distances w/ little to no noise and distortion degrading the signal

Signals are regenerated rather than amplified

283

the 2 most commonly used digital modulation schemes that use a combination of changes

QPSK and QAM

284

QPSK has ____ Phase states

4

285

A combination of QPSK and ASK

QAM

286

Device used to analyze digital signals

QAM Analyzer

287

Graphic depiction of digital signals

Constellation

288

Ratio of the error power to the average power in the ideal QAM signal

MER

289

Bits are added to the digital signal in order to detect errors

FEC

290

Errored bits compared to total bits

BER

291

The position on a waveform cycle at a specific point in time

Phase

292

Digital power measurement is _______ power

Average

293

Analog power measurement is ____________ power

Peak

294

Peak power of a carrier is known as

Amplitude

295

Standard for cable modems

DOCSIS

296

Terminates, manages, translates HSI between the Cable Modems on the HFC LAN and other devices on the WAN

CMTS

297

Decodes ethernet signaling info for incoming packets and applies filtering rules

Router (Ethernet Router)

298

Difference between the incident signal and the reflected signal is called:

Return Loss

299

This laser is good for many channels, has low noise and is good for long distances

DFB (Distributed Feedback)

300

Laser that is noisy and only good for a few channels and short distances

F-P (Fabry Perot)

301

Light travels in the core of the fiber because of this concept:

Total Internal Reflection

302

The ratio of the velocity of light of 2 mediums is called

Index of Refraction

303

Light reflected in the core is called

Total Internal Reflection

304

Light travels faster in the ______ because it has a ______ Refractive index than the ________

1) Cladding2) Lower3) Core

305

How is light amplified in a LASER?

Stimulated Emission of Radiation

306

Which ANSI Class laser is a hazard if the direct or reflected beam is viewed?

Class 3B

307

ANSI Class laser hazard if the beam is collected on the eye

Class 3A

308

Example of a Class 3A laser

Laser Pointer

309

ANSI class laser hazard if beam is viewed

Class 2/2A

310

Example of a Class 2/2A laser:

Barcode Scanner

311

All of the losses between Optical Transmitter and Receiver:

Loss Budget

312

1mW = _____dBm

0dBm

313

10mW = ____dBm

10dBm

314

A doubling/halving of the optical power (mW) is equal to a ______dBm change

3dBm

315

Splice loss is measured using a ______

OTDR

316

Equation to convert mW to dBm

10Log(mW)

317

Equation to convert dBm to mW

10^(dBm/10)

318

Fiber is in tubes much larger than the fiber allowing the fiber to move freely in this cable configuration

Loose Tube

319

Similar to loose tube but has 2 steel strength members in the jacket

Flex Tube

320

A method of attaching 2 fiber ends w/ a plastic form to align the fiber ends

Mechanical splice

321

Clean fiber with this liquid:

at least 90% Isopropyl alcohol

322

A temporary splice that uses and index matching gel

Mechanical splice

323

Removes the coating from the fiber

Fiber Stripper

324

Scores then breaks the fiber

Cleaver

325

Uses an electrical arc to join two fibers

Fusion splicer

326

Comcast spec for splice loss

.05dB

327

Uses a computer program and a video magnifying system to align the fiber ends for splicing

Profile alignment

328

Uses a transmitter and a receiver to determine if the fiber ends are aligned before splicing

LID (Local Injection and Detection)

329

A string used to separate and cut the outer jacket and armor

Rip Cord

330

Splice kits should be bonded to the strand using a _______ and a _________

#6 ground wire and a strand clamp

331

According to the NCT5 book, name three places to store fiber paperwork

1) Splice Trailer2) Restoration Kit3) Headend

332

This is described as the widening of light pulses

Dispersion

333

This fiber connector offers a good balance between loss and reflections

SC

334

This fiber connector is the most commonly used

SC

335

This fiber connector provides a notch and screw connection

FC

336

This fiber connector end has a flat cut... Reflections travel straight back to the source

UPC

337

This connector end directs reflections into the cladding

APC

338

What is used to clean fiber connectors?

Dry wipe cleaning tape dispenser

339

What is used to clean fiber receptacles?

Lint free wand/swab

340

interface between the headend and the RF plant

Node

341

How many nm apart are the DWDM wavelengths? How many GHz is this?

.8nm100GHz

342

What is the optimum optical input to a node in dBm and mW?

0dBm1mW

343

This part of the optical receiver detects light and converts it to RF

Photodiode

344

List the two optical amplifiers

EDFAYEDFA

345

Having an alternate feed for backup is called

Redundancy

346

This is used to visually see losses, breaks and distance measurements in the fiber link

OTDR

347

The ______ uses backscatter to make measurements

OTDR

348

Main source of loss in fiber

Scattering (Rayleigh)

349

The downward slope of the OTDR trace shows

Attenuation

350

Connectors will have both ________ and _______ on the OTDR trace

Reflection and Loss (or attenuation)

351

The distance the OTDR can't see is the _______ ______

Dead Zone

352

To overcome the dead zone, you should use a ________ _______ to make up for it

Launch Jumper

353

Device that measures light power

Optical Power Meter

354

Measures light loss

OTDR

355

This is typically considered an upgrade where some trunk cables have been replaced by fiber and bandwidth is not increased

Trunk Reduction

356

This is where the entire trunk is replaced with fiber, the entire distribution in replaced w/ new cable and electronics. This is considered a rebuild

FTTF (Fiber to the Feeder)

357

All actives are removed except for the node. there are no cascades and only taps after the node

FTTC (Fiber to the Curb PON)

358

This is a PON with no active components between the headend and subscriber with a single fiber dedicated to each sub

FTTH (Fiber to the Home)also known as out current FTTP (Fiber to the Premise)

359

Device that measures pulling tension applied to the cables

Dynamometer

360

Device that prevents excessive pulling tension applied to cables

Breakaway swivel

361

Clearance at the pole between cable and power

40"

362

Device used to prevent strand sag when installing strand

Strand Brake

363

Scanning down the road 12-15 seconds equals what distance range for city driving?

1 to 1-1/2 blocks

364

Scanning down the road 12-15 seconds equals what distance range for Highway driving?

1/4 to 1/2 mile

365

The 3-4 second rule is used to determine

Following distance

366

Before climbing a ladder that is 20' tall, how far should it be pulled from the base

5'

367

Max vehicle slope to go up in an aerial lift

5*

368

Safe approach distance to wires containing up to 300VAC

No contact

369

Resistance of a circuit to AC

Impedance

370

Pulling technique used for very long cable pulls through ducts

Mid Pull

371

CRAN

Converged Regional Area Network

372

Variation in delay, arriving sometimes in the same order but different time spacing between packets

Jitter

373

Delay in time of arrival of packets

Latency

374

QOS

Quality of Service

375

DQOS

Dynamic Quality of Service

376

CBONE

Comcast Backbone - Connects regions or CRANs

377

Mathematical representation of an Analog Signal

Digital Signal

378

A continuously varying signal

Analog Signal

379

Optical power units (two)

mWdBm

380

RF Power Units (two)

dBmVmV

381

Good Isolation in the headend combining reduces:

Adjacent Channel Interference

382

In NCT5 book, how man dB is good isolation?

25dB

383

This fiber topology reduces amp cascades and improves picture quality

Trunk Reduction

384

Cost effective way to get many optical signals transported

WDM

385

an OTDR uses this to make measurements

Backscattered light

386

If you want to OTDR great distances, you must increase the _________ _________ to see farther down the fiber

Pulse Width

387

The difference between the incident signal and the reflected signal

Return loss

388

Directs frequencies of one bandwidth to one port and frequencies of another bandwidth to another port

Diplex Filter

389

What is the angle of an APC connector?

8-12 degrees