nct4 v2 Flashcards
1
Q
Random electron activity in the atoms that make up the conductor
A
Thermal Noise
2
Q
Noise floor in a 4MHz bandwidth @ 68*F is called:
A
Termination Noise
3
Q
Difference in a peak carrier level to the noise floor:
A
Carrier to Noise
4
Q
Amount of noise in a 4MHz bandwidth on a 75 Ohm cable @ 68*F
A
-59.16dB
5
Q
FCC Spec for C/N
A
43dB
6
Q
Undesired change in the waveform of a signal
A
distorion
7
Q
Crossing of Modulation from one channel to another
A
XMOD or Cross Modulation
8
Q
XMOD appears as
A
Vertical bars in the picture
9
Q
2nd harmonics of any 2 channels are typically _____ below the sum/difference products
A
6dB
10
Q
CTB products fall within _____ of the video carrier
A
30 KHz
11
Q
Tilting the output of an amplifier improves:
A
Distortion performance
12
Q
CSO beats fall @ __________ above the video carrier
A
1.25MHz +/- 15 KHz
13
Q
unwanted sum/difference frequencies resulting from heterodyning of 2 or more signals
A
Beats
14
Q
A horizontal bar in the picture is _______ Modulation
A
Hum
15
Q
Primary cause of Hum (60Hz)
A
Power Passing Choke (60Hz)
16
Q
A source of hum in older systems (120Hz)
A
Series regulated DC Power supplies (120Hz)
17
Q
3 parts of fiber
A
Coating, Cladding, Core
18
Q
When light stays in the core, this is called
A
Total Internal Reflection
19
Q
2 wavelengths used in HFC Networks
A
1550nm & 1310nm
20
Q
Most common type of fiber used in the cable industry
A
Single Mode Fiber
21
Q
Wavelength is ________ proportional to frequency
A
Inversely
22
Q
A shorter wavelength means a _______ Frequency
A
Higher
23
Q
Compares the speed of refracted light in a material to the speed of light in a vacuum
A
Index of Refraction
24
Q
One Billionth of a meter
A
nanometer
25
Device that takes the RF and modulates it onto an optical wavelength
Optical Transmitter
26
Optical transmitters use this type of diode
Laser Diode
27
What device detects light and demodulates it to RF
Optical Receiver
28
An optical receiver uses this type of Diode
Photo Diode
29
C/N Formula
L1-(NF-59.2)
30
Formula for C/N @ end of cascade
C/N1-10logN (C/N1 is equal to the C/N of a single amplifier in the cascade, N=Number of amplifiers)
31
XMOD Formula
XMOD1 - 20logN
32
CTB Formula
CTB1 - 20logN
33
Devices that are used to compensate for the forward and return loss
Amplifiers
34
What device compensates for the uneven cable loss in coax?
Equalizer
35
Amplifier input EQs are selected to do what?
Provide flat inputs to the first stage of amplification
36
amplifier interstage EQs are selected to do what?
Provide output tilt
37
Forwards trunk amplifiers are selected for their what?
Low Noise Figure (NF)
38
What compensates for fluctuations in the input signal?
AGC
39
The name of the frequency that is monitored by the AGC
Pilot
40
It provides a means to monitor levels with out interrupting service
Test Point
41
This device has substantial isolation between it's output & tap port:
Directional Coupler (DC)
42
What device has both a DC & Splitter built into it?
Tap
43
What device is considered to be the customer interface point?
Tap
44
This device compensates for reverse tilt on the feeder
In-Line EQ
45
This device has a diplex filter & a pad that will only affect the return
In-Line Conditioner
46
This device uses a low pass filter to prevent RF from entering the Power Supply
Line Power Inserter (LPI
47
This map only shows the poles & Strand
Strand Map
48
This map is the point where actives are added to the network
Design Map
49
This map shows the network changes from the original design as the design needed to be modified when it was being built
As-Built
50
This map shows only one Node
HFC Plant Map
51
The numbering system used to catalog plant maps is called:
Map Grid System
52
CLI
Cumulative Leakage Index
53
Leaks _____ and greater are included in the CLI calculation
50uV/m
54
CLI is performed how often?
annually
55
What form is used to submit CLI to the FCC?
320
56
Leakage monitoring must be performed how often?
Every 90 days
57
During Leakage monitoring, leaks _____ and greater must be logged and repaired
20uV/m
58
Leakage logs must be kept on file for how many years?
2
59
Signal levels that are ________ or higher must be offset
38.75dBmV
60
A method used to pin point a leak
Triangulation
61
FCC requires that measurements are made with a ______ antenna
Dipole (1/2 Wave Pole)
62
CTB falls within ______ of the video carrier
30KHz (all channels EXCEPT 5 & 6)
63
AM
Amplitude Modulation
64
PM
Phase Modulation
65
FM
Frequency Modulation
66
Modulation used for Video
Amplitude Modulation
67
Modulation used for Color
Phase Modulation
68
Modulation used for Audio
Frequency Modulation
69
The video carrier is ______ higher than the lower edge of the channel
1.25 MHz
70
The color carrier is ________ from the video carrier
3.58 MHz (4.83MHz from lower edge of channel)
71
The audio carrier is _________ from the video carrier
4.5 MHz
72
CSO fall ________ above the video carrier
1.25MHz +/- 15KHz
73
CTB are within _______ of the video carrier
30KHz
74
The speed at which a wavefront passes through a medium, relative to the speed of light.
Velocity of Prorogation
75
The difference in voltage between one point and another is called
Potential Difference
76
Substance that allows heat or electricity to pass along or through it is called
A Conductor
77
The difference of an electrical field in radiated wave is
Polarity
78
Subatomic particles found in atoms that balance out the positive charge of a proton (within the nucleus) with their negative charge
Electrons
79
An electrical current, of which the polarity is periodically reversed
Alternating Current
80
Frequency Divided by the speed of light =
Wavelength
81
_____ is the amount of time it takes an AC waveform to complete one cycle
Period
82
The peak value of an AC waveform is also known as its
amplitude
83
1 complete sine wave =
Cycle
84
number of an AC waveform that occur in 1 second
Frequency
85
Ohms Law
E=IxR
86
R=
the resistance in Ohms
87
E=
The electromotive force (EMF) in volts
88
I=
The current in Amperes
89
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
90
A representation of the networks response to a sweep signal and the effects of all the network components such as cable, connectors, passive devices, and the signatures added by the amplifiers
Sweep Response
91
The difference in cable attenuation or amplifier gain between lower and higher Frequencies on the network
Tilt
92
The difference in gain between the ends of a band of frequencies
Slope
93
A gradual or sharp attenuation of gain (versus Frequency) at either or both ends of the spectrum
Roll-off
94
a sharp reduction in the amplitude of a narrow band of frequencies within the networks overall response
Suck out
95
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
96
Small plug-in device used to attenuate signals to the correct operating levels
Pad
97
A device used to reduce signal strength
Attenuator
98
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
99
The effect a particular type of amplifier has on the overall frequency response
Signatures
100
the difference between in amplitude between the most positive (Peak) and the most negative (Valley) levels of a electrical signal
Peak to Valley
101
Outline or multiple images of the primary TV picture offset to either side
Ghost
102
Caused by direct pickup (off air signal getting into the cable system)
Leading Ghost
103
An oscillator controlled so that it maintains a constant phase angle relative to a reference signal source
Phase Locked
104
Usually caused by signal reflection
Following Ghost
105
The unwanted sum and/or difference frequencies resulting from heterodyning (mixing) of two or more signals
Beat
106
A method of reception using an RF current of the proper magnitude and phase relation so the received voltage is if the same nature as the original wave
Zero Beat
107
caused in one channel by the same carrier from another transmitter operating on the same channel
Co Channel interference
108
chemical change caused by a reaction to Oxygen such as rust
Oxidation
109
A theoretical temperature equivalent to the absolute absence of heat equal to - 273.15 degrees C or -459.67 degrees F
Absolute Zero
110
Noise added to the response due to a lack of or improper termination
Termination Noise
111
A frequency selective receiver capable of tuning in a desired frequency/Channel with a display showing RF signal strength (dBmV)
Signal Level Meter (SLM)
112
The minimum signal level at the input to the customers TV is
0dBmV to 15dBmV
113
what do you need to do to maintain an SLM
Keep the battery charged, clean the battery terminals regularly,keep the SLM clean by wiping it gently:dry the display screen to prevent spots, do not use any type of polish or cleaner on the display ,and a regular calibration should be made and logged,
114
The ratio of error power to average power in an ideal QAM signal is
MER
115
Average power =
Digital power
116
Peak Power=
Analog power
117
Optical power units
mW or dBm
118
RF power units
mV or dBmV
119
Attenuation/ gain units
dB
120
what mode monitors up to 12 chs at a time on your meter
Miniscan
121
what mode monitors the entire Ch plan on your meter
Full scan
122
what mode check s the forward low frequency and high frequency channel tilt
Tilt mode
123
Detects errored bits in the system
Bit error Rate (BER)
124
used for troubleshooting connections with intermittent bit errors occuring over a period of time
Errored Seconds
125
passage of an outside signal into the cable; can result in noise and disruption of the desired signal
Ingress
126
shows impairments on the networks with the patterns on display and can be identified by figuring out the patters
Constellation Graph
127
Displays intermittent short duration impairments missed by MER and BER on your meter.
Digital quality index (DQI) mode
128
this mode shows you if ingress is within the downstream digital spectrum without turning of service
QAM ingress mode
129
This mode greatly improves the success rate and efficiency in locating return-path ingress
Fieldview Option
130
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
131
Provides a quick method to check cable system integrity, using active channels to sweep the forward path is
Sweepless Sweep
132
Using a unique method to accurately reveal any problem in the system without interfering with any of the analog/ Digital carriers is
Forward Sweep
133
Helps find mismatches or other problems in the upstream transmission path
Reverse Sweep
134
Accurately measures Ac voltages of signals other than pure analog sine waves
Root Mean Square Meter (RMS)
135
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)
136
is used to find the location/path of underground cables
Cable locator
137
has a transmitter and receiver. it could include the following components a test lead, inductive frame and A-frame.
A locator
138
The resistance of a circuit to alternating current.
Impedance
139
The condition that results when two components of a system are operating at different impedance
Impedance Mismatch
140
is used to determine the distance of a known fault from a specific location
Time Domain Reflectometer (TDR)
141
Is used to locate: bad or unknown splices, opens, shorts, and kinked cable.
TDR
142
A reflection with the same polarity indicates an
open
143
is a situation where the center conductor comes in contact with the shield
Dead Short
144
A reflection with the opposite polarity indicates that the fault is
Short
145
refer to a cable that has not been competely cut
Partial Open
146
The contact between the center conductor and the shield is not complete
Partial Short
147
The distance that cannot be seen by the TDR because its too close to the TDR source
Deadzone
148
two types of TDRs
Waveform and Digital
149
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
150
A device that generates a light source used in fiber communication
Laser
151
LASER
Light Amplification by Stimulated Emission Radiation
152
Most light generated by lasers for telecomm use exists in the infrared band of 1310nm and 1550nm wavelengths
Infrared Light
153
the distance between two points of like phase in a wave
Wavelength
154
A card made up of material similar to photographic film that changes colors when exposed to light
Photosensitive Card
155
Laser Classification
Class1-safe as long as they are not disassembled.; Class-2/2A Eye hazard if beam is viewed.;Class-3A Eye hazard if collected or focused on the eye.; Class3B Eye hazard if the direct or reflected beam is viewed.; Class4 eye and skin hazard.
156
what is the laser standard
ANSI Z-136
157
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
158
what are the two methods of fiber cleaning
Wet and Dry
159
Materials needed for wet method
Lint free wipes, Isopropyl(better than 90%) as recommended by the manufacturer, and lint free swabs or urethane foam heads
160
rotate a cleaning cloth over the end of a fiber connector by pushing down toward the connector
Push Pen
161
A battery or generator that provides electrical power to the circuit. For example, batteries and generators
Power Source
162
A conductor such as copper wire
Path
163
the device that uses the electricity. it is any device that draws current
Load
164
Substance that allows heat or electricity to pass along or through it
Conductor
165
Subatomic particles found in atoms that balance out the positive charge of a proton with their negative charge
Electrons
166
is the electromotive force that causes electrons to flow in a circuit
Voltage (E)
167
The pressure that causes electrons to flow in a circuit
Electromotive Force
168
is the flow of electrons through a conductor. is measured in amperes and is designated mathematically in ohms law as the letter I
Current (I)
169
The amount of electrons that pass a given point in the conductor in one second
Coulomb
170
is the opposition a material offers offers to the flow of current
Resistance (R)
171
the difference in voltage between one point and another
Potential Difference
172
the direction of an electrical field in a radiated wave
Polarity
173
An electrical current of which the polarity is periodically reversed.
Alternating Current (AC)
174
the point at which the filament reaches a temperature that causes it to glow
incandescence
175
the relationship between current or voltage and elapsed time
AC Waveform
176
what are the 4 types of AC Waveforms
Sine Wave, Square Wave, Quasi-square wave, and Sawtooth Wave
177
this waveform represents the characteristics of the voltage/current that feeds homes, powers power supplies, and the television channels that carry the program information to your customers homes
Sine Wave
178
This waveform is often found within the switching regular DC output power supplies in Amplifiers
Square Wave
179
A CATV power supply without a load produces a near square wave that combines a non linear increase and decrease of voltage or current with extended maximum positive and negative peak value.
Quasi Square Wave
180
Types of signals carried on the HFC system
Modulated RF carriers, Modulated analog carriers, DC power and AC power
181
one complete sine wave is
Cycle
182
Number of cycles of an AC waveform that occur in one second
frequency
183
the speed of the light/Frequency=
Wavelength
184
the amount of time it takes a waveform to complete one cycle
Period(T)
185
peak value of a waveform
Amplitude
186
states that current is directly proportional to voltage and inversely proportional to resistance
Ohms Law
187
R=
The resistance in ohms
188
E=
the Electromotive force(EMF) in volts
189
the rate a which work is done or the rate at which energy is used
Power
190
I=
current in Amperes
191
Resistance is measured between the center conductor and sheath with the other end
DC Loop Resistance
192
P=
WAtts
193
Current at any point in the line in the HFC plant is equal to the sum of the individual Ampere current draws of the active devices being fed from that point.
AC Current in the Broadband Network
194
the amount of voltage loss over the span is referred to as
Voltage drop
195
At lower voltages the current is higher in the HFC plant
Current at lower voltages
196
the amount of energy available to move a certain number of electrons from one point to another in an electrical circuit
Voltage
197
to be subjected to the action of an electrical discharge
Shock
198
to kill by electrical shock
Electrocute
199
a connection to the earth or a grounding device
Ground
200
power supplies reduce the secondary power (120 or 240) to the 60 or 90VAC for insertion in the cable
Line power supply
201
the electricity provided by the local power company
commercial power
202
2 types of line power supplies
standby and non standby
203
reduction of voltage by a transformer
stepped down
204
conversion of voltage, in this case from 36 or 38VDC to 60 or 90VAC
Inverted
205
the point where AC power from the power supply is placed on the coax portion of the distribution network.
Power inserter
206
a filter that will only allow the higher RF frequency signals to pass directly from RF port to port
high pass filter (relating to power inserter)
207
a filter present on each leg to direct the flow of the lower frequency AC power, which prevents the RF Signal from traveling into the power supply and causing signal leakage
Low Pass filter(Relating to power Inserter)
208
the two types of network powering
Distributed and centralized powering
209
batteries produce what kind of gas during charging operations
Hydrogen
210
three methods for testing batteries
battery load test, battery voltage test, battery conductance test
211
the most accurate and reliable test involves testing the batteries under a load condition
Load Test
212
the difference between any batteries in the set should not be greater than
0.3VDC
213
measuring the impedance of the battery with a conductance meter and documenting that value when its new. Batteries less than 50% of their as new conductance values are known to be bad
Battery conductance test
214
means of testing the network remotely that saves numerous problems in respect to downtime and customer dissatisfaction
status monitoring
215
according to manufacturers the terminals should be torqued to_____and then retorqued to _____ during routine maintenance.
75inch lbs and 60 inch lbs
216
what points should be kept in mind while checking battery terminals
is there an in line fuse in the battery cable, check the fuse holder and fuse. make sure the terminals are properly greased with an approved corrosion inhibitor such as NCP-2 or NO-OX
217
the topology where signals originate in the headend and are transmitted long distances via trunk cables which have branches for directing the signal to customers
Tree and Branch
218
Forward signals originate at the headend are transmitted downstream by way of the trunk to the ends of the service.
Transportation (Trunk)
219
In a Tree and Branch system the feeder is considered what
The distribution System (Branches)
220
in a tree and branch system RG-6 and 11 is considered
The Drop(Leaves)
221
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)
222
what are the two wavelengths of fiber do we use
1310 nm and 1550nm
223
a network architecture where nodes, hubs, or headends may be connected with fiber optic cables to provide redundancy or increase services.
Ring
224
What are the advantages of fiber
Greater Bandwith and can travel greater distances without Amplification
225
what are the two types of Fiber
Single mode and Multi mode(we use single mode)
226
what is the attenuation of single mode fiber
1310nm=.35dB/km, 1550=.25dB/km
227
the distance between two points of like phase in a wave
wavelength
228
compares the speed of light through a material to the speed of light through a vacuum
Index of Refraction
229
the reflection that occurs when light strikes an interface at an angle of incidence greater than the critical angle allowing it to be continually reflected from the interface between two materials with different refractive indices
Total Internal Reflection
230
Single mode core is how many microns
8 to 9 microns
231
single mode cladding is how many microns
125 microns
232
single mode coating is how many microns
250 microns
233
what is the primary loss in fiber called
Scattering
234
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
235
separates or combines the AC currents two parts-( AC power and RF broadband signals)
Power Diplex
236
attenuates the signal in order to bring it to within the acceptable range of the amplifier
Pad
237
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
238
Usually selected for low noise figure. Amplifies forward signal passing through the trunk and distribution lines
Forward Amplifier Module (TRUNK)
239
Used to compensate for fluctuations of the input signal
AGC
240
Similiar to an AGC maintains the proper tilt(caused by temperature change in a specified amount of coaxial cable) and output level despite changes in the input signals
ALS
241
Signal splitting device that plugs into a trunk/bridger chassis
directional plug ins (feedermaker)
242
Converts AC power(60V-90V Quasi Square wave) to DC power(typically 24VDC)needed to operate the stations modules and regulates the DC output voltages to provide a stable and constant output
DC Power Pack
243
used to direct AC power into and out of specific ports of the amplifier station
Power Director
244
provides a means of monitoring the various inputs and outputs without interrupting service
Test Points (TP)
245
will have substantial isolation between the output and tap ports if all ports see a good 75 ohm match. Isolation for signal paths between the tap and output port is usually 25dB or greater
Directional Coupler (DC)
246
A tap is used to extract a specific amount of signal from the feeder system and distribute it for connection of customer drops and contains a directional coupler that feeds a single splitter.
Taps (Customer interface point)
247
Low frequency signals are not attenuated as much as high frequency signals in a coaxial cable
In line Equalizers
248
LIke in line EQs these devices are sometimes installed in the distribution cable where low value taps are used
in line conditioners
249
in a housing like the splitter is used to introduce AC power into the network
Power Inserter
250
A design philosophy where the loss of the cable and other passive devices before an amplifier station
Unity Gain
251
similar to a street map and includes features like lakes and rivers, streets, and boundaries
Base Map
252
Displays streets with poles and pedestals locations and includes the span length or footage between these items
Strand Map
253
Shows the locations of electronic equipment. including headend and any hubs,amplifiers, power, supplies, and taps.
Design Map
254
Offer the layout of the system in a condensed form. shows how active devices are cascaded and how they are connected to the headend, hub, or node. power supplies are also noted
Amplifier schematics or Tree Map
255
A corrected map that represent the addition or changes in information on the design map
As Built map
256
Map that covers a single node
HFC Plant map
257
documents a fiber plant
fiber design map
258
catalogs the system maps
Map Grid System
259
is the measure of the cables ability to maintain impedance at all frequencies due to the many micro reflections introduced during manufacturing. The industry Specs call for a minimum of 15dB, but the higher the better
Structural Return Loss (SRL)
260
What do reflections do on a coaxial cable
They distort the carriers, causing bit errors in the modulated data streams.
261
a thin wire wrapped around the fiber and coaxial cables to secure them to the strand
Lashing wire
262
load bearing component of an aerial coaxial cable installation. Its usually a 1/4 or3/8 inch zinc coated steel wire to which the cable is lashed
Strand
263
A loop intentionally formed in the cable to compensate for the expansion and contraction caused by temperature changes
Expansion Loop
264
used to counteract the horizontal component of forces placed on poles by the strand and cable
Guy and Anchor
265
Strand that connects the pole line hardware to anchor
Guy
266
Buried metal device used to transfer force from the pole to ground
Anchor
267
strand that connects the pole line hardware, particularly the guy attachment hardware to the anchor.
Guy Wires
268
is a yellow plastic cover used to protect the guy wire and make it more visible
Guy Wire Guard
269
Different types of Guys
Down Guy, Head Guy, Terminal Guy, Side Guy, Pole to stub guy, pole to pole guy, sidewalk guy, and storm guy
270
Different types of anchors
screw anchor, never creep anchor, rock anchor, anchor rods(AKA Guy rods)
271
the device usually a screw used to connect the coax's center conductor to an active or passive device
Seizure Mechanism
272
is used to remove the outer jacket of a typical underground cable
stripping tool
273
may remove the jacket, but primarily removes the outer sheath and dielectric within the cable
Coring Tool
274
having a saw toothed edge or margin notched with tooth like projections
Serrated
275
these tools are specifically designed to cut coaxial cables
banana cutters
276
what are the two steps in building the aerial portion of the network
the strand system must be built and properly tensioned and the cable must be lashed onto the strand.
277
to wrap a thin wire around the cable in order to secure it to the strand.
Lashed
278
this device is selectively placed at pole hardware locations to prevent dangerous sag while strand is being installed
Strand Brake
279
used in conjunction with a lay up stick to lift cable blocks and strand
Wire raising tool
280
used to prevent unwanted payoff of strand from the cable trailer or reel stand
Reel Brakes
281
are portable bonding connections installed at the location where the strand is spooled from the cable trailer or reel stand. can be removed only after the strand is bonded to the grounding network
Traveling grounds
282
two types of strand methods
Stationary reel method and Moving reel method
283
installation of pole hardware allowing for hanging of strand
Framed
284
the trailer should be at a minimal distance (two times the hardware attachment height) from the pole at which the strand first contacts the pole line hardware
Stationary reel method
285
the strand is installed by mounting a reel to a vehicle and driving the vehicle from pole to pole stopping to install the strand and hardware at each location
Moving reel method
286
Strand splices should be placed outside the pole framing hardware, but within 18 to 24 inches of the pole . traveling grounds should always be used when placing the strand
Stationary reel method
287
uses a mechanical wrenching action to bend expansion loops into coaxial cable prior to lashing or during splicing
Mechanical Bender
288
used to measure the pulling tension applied to cables
Dynamometer
289
allows cables that are being pulled to swivel and are used to ensure that the cables are not over-tensioned during pulling
Breakaway swivel
290
used to support a single lashing may be used when cables are lashed directly to the strand or in overlash applications
Single roller Block
291
used to install self support cable and is attached to the pole hardware support the cable as it is pulled out
Pole Mount Cable Block
292
used to support a single cable prior to lashing
Economy Block
293
This device is used to route cables through inside or outside corners up to 90degrees. it minimizes drag on the cable in corners and ensures that the minimum bend radius of the cable, as specified by the manufacturer is not exceeded
90 degree corner block
294
used to route cables through inside or outside corners up to 45degrees. it minimizes drag on the cable in corners and ensures that the minimum bend radius of the cable is not exceeded
45 degree corner block
295
used to guide cables from the cable trailer or reel strand to the strand
Set up Chute
296
this bracket is used to support 45 and 90 degree corner block or setup chutes at the mid span
set up bracket
297
used to lash cable directly to installed strand or cable bundles
cable lasher
298
allows multiple cables to be pulled into place when lashing cable directly to strand
Multiple cable puller
299
allows multiple cables to be pulled into place in overlash applications
Overlash cable puller
300
device is used to push equipment ahead of a pulled lasher
Cable block pusher
301
pushed in front of a lasher by a cable block pusher to uniformly position multiple cables that are being lashed
Cable positioner (Magic Box)
302
is the tension caused by the mass of cable on the reel and reel brakes.
tail loading
303
what two methods control tail loading
can be minimized by using minimal braking during the payoff of the cable from the reel. and at times no braking is preferred.
304
If a span is _____ or longer place ____ expansion loops on each pole. one is placed on the input side and one is placed on the output side of the pole
250ft and 2
305
is when two perpendicular strands end at the same pole
Double dead end
306
the mechanical bender must remain in place until the lasher is transferred and the next span of cable is
lashed 50ft or 1/3 the distance to the next pole whichever is greater
307
An expansion loop should be formed on the ___ side of every pole for all sizes of coaxial cable being used
Output
308
When the loop location is dictated by the signal flow direction of the feeder cable
Feeder Dominant
309
the trailer should be positioned in line with the strand and twice the distance _____
of the set up chute to the ground from the chute (Stationary Reel method)
310
The cable should payofff the___
Top of the cable reel
311
Use a cable block lifter to place _____ on the strand every 30 to 50ft
cable blocks
312
the ends of the cable left at the pole for splicing
Cable Tail
313
it is essential that double lashing be used when___
two or more cables, all trunk cables, and at street crossings.
314
how many feet do you stop the lasher to form an expansion loop
6FT
315
is a connection to earth or a conductor serving earth potential and can be intentional or accidental
Ground
316
is the interconnection through good conductors of the cable plant with power and phone systems to eliminate potential voltage differences
Bond
317
is a pipe usually made of PVC and used to house cable and protect it from dirt, moisture, and outside forces.
conduit
318
is a protective covering for hardline cable, typically made from galvanized steel or plastic over the exposed cable where it makes the transition from aerial to underground.
Riser Guard
319
conduit for underground drops must be buried to a minimum depth of
8inches
320
installing all underground drops emerging from the ground must have physical protection (cable guard or conduit) to a point at least ________located at the house
4ft above ground or until reaching the service enclosure.
321
underground drop cables routed down a pole must have physical protection, cable guard, or conduit, to at least
8ft above ground and at least 8inches below ground
322
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
323
bury warning tape above the cable at a depth of___ during the back fill process
12inches
324
Locate the midpoint of the pull. while monitoring pulling tension, pull the cable from the mid point to the end of one direction.(Used for installing long fiber runs)
Mid point cable pull
325
what u do with the remaining fiber optic cable
figure eighting
326
while doing the figure eights with fiber u set the cones up ____ apart
10-15 paces
327
the US government agency established in 1934 to regulate electronic communications
Federal Communications Commission(FCC)
328
In 1990, the FCC required that system perform s CLI test ____
Annually
329
a figure of merit derived mathematically from the number and severity of signal leaks in a cable system.
Cumulative Leakage Index
330
the figure of merit for CLI has to be
64 or less
331
your CLI test that you do annually has to be submitted using what form
FCC form 320
332
a system in which transported signals are completely contained within the medium is called
a closed system
333
Leakage is emitted RF energy and is called
Egress
334
Noise is received energy and is called
Ingress
335
what % of leakage is found between the tap and bonding block
70%
336
LTE
Long Term Evolution
337
LTE operates in the ____frequency range
700 to800 MHz
338
No more than 15 microvolts per meter @30 meters
0-54MHz
339
No more than 15 microvolts per meter @30 meters
More than 216MHz
340
No more than 20 microvolts @3 meters
54MHz and 216MHz
341
the aeronautical frequencies are
108-139MHz
342
two ways to do the CLI test
Ground based and flyover
343
Leakage monitoring must be done
Quarterly
344
Leakage logs must be kept on file for
2yrs
345
Only Leakages___ or greater are included in the CLI calculations
50 microvolts
346
CW
continuous wave
347
three methods to calibrate your leakage detector
Done by the manufacturer, Direct coupling, and Antenna
348
what method do you use to pinpoint a leak
Triangulation Method
349
a leakage log should include
Date;location;leakage cause;strength;distance to leak; Date;Strength after repair.
350
leaks__ or greater must be logged for regular monitoring
20 microvolts
351
the FCC requires that __ of the plant be tested for CLI. The comcast standard is _____
75% and 100%
352
The CLI is done at an altitude of ____, using 108 to 137MHz band
1500ft(450Meters)
353
Sending AC from two different power supplies, causing a large spark
bucking power
354
Comcast troubleshooting steps
Identify, Isolate,Fix,Verify
355
a low resistance connection between two points in an electric circuit that forms an alternative path for a portion of the current
Shunts
356
Steps for verifying a backwards tap
1) the tap plate and re-check the input port. 2)if there is no signal present, check the output port. 3) if signal is present here, the housing is backwards and requires re-splicing.
357
if you encounter a conductor that is 300v or less
avoid contact with the conductor
358
if you encounter a conductor that is between 300V and 750V
stay at least 12 inches away from this conductor
359
do foreign voltage detectors DC voltage
NO
360
Divide and conquer does what
reduces repair time.
361
the reverse path must be balanced for___ just as the with the forward system
unity gain
362
threshold for ingress at 5-18mhz
-20dBc (Decibels relative to carrier)
363
threshold for ingress at 18-42mhz
-35dBc (Decibels relative to carrier)
364
Max min sweep formula
N/2+1.5=
365
telemetry reverse sweep formula
N/2+1=
366
is defined as two or more customers without service or with impaired service, due to the same root cause
outage
367
is a plant fault with overlapping correlated trouble call
priority plant fault
368
is a signals inability to be transmitted from one cable or device to another cable or device and measured in dB
Isolation
369
is the difference in dB, of a signal level, injected into one output port, and the measured level of the same signal on another output port with the input port properly terminated
port to port isolation
370
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
371
a node has a minimum of
One optical receiver, one optical transmitter, power supply, and a forward and return amplifier module
372
is an amplifier used to transport signals to longer distances
trunk amplifier
373
used to add to the strength of signals in order to compensate for higher loss of the feeder and to provide enough signals for the drop cables and for multiple customers
Bridger amplifiers
374
are high gain amplifiers and are operated so that the output levels are higher as well
Line extenders
375
samples the stations output level using the directional coupler 15 usually at a specific frequency or channel. used to compensate for fluctuations of the input
Automatic gain control
376
recovers the RF information modulated onto the optical carrier at the headend
Optical detector
377
refers to the percentage of optical modulation, per channel, driving a laser transmitter
Optical modulation Index(OMI)
378
for every db change in optical power there is a 2db change in RF
know that rule
379
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
380
whatever tilt u need multiply by 1.25 to get desired eq
know this rule
381
has attenuation that duplicates that of a cable.
Cable Equivalency (Cable simulator)
382
used for the first stage of amplification for a trunk or multi output station, picked for its low noise figure
integrated circuit (IC)
383
this device monitors the change in temperature and makes an attenuation and tilt change based on typical cable spacing between stations
thermal level control
384
this is usually a power double device
second stage gain
385
is used to compensate for frequency response signatures of passive and active devices in the system,
Response network/Mop up
386
circuitry used to adjust the frequency of an amplifier
response network
387
usually a passive network placed between the input and output amplifier module. it is used to correct fro a frequency response problem seen at the output of the amplifier
mop up
388
the deviation in response at the output of an amplifier or passive device when compared to the response st its input.
signatures
389
used to set the amplifiers output tilt.
interstage Equalizer
390
a measure of an amplifiers output level to the level of distortion it produces
output capability
391
is used to inject return test signals for alignment/sweep of the return portion of the amplifier
Insertion point
392
Reverse pad=amplifier upstream design gain-total span loss
know this rule
393
have forward and return on the same test point
bi directional test points
394
RF portion of the cable plant fed from a node
Node service area
395
we can utilize a 3% ____ without excessive distortion with a carriage of 100 channels
OMI
396
is the actual seep response before normalization
raw sweep
397
is the exponent or the power to which a fixed number(the base) must be raised in order to produce a given number
logarithm
398
the number of times the base is multiplied by itself
exponent
399
1)any number raised to the exponent 0 is equal to 1.2)any number raised to the exponent 1 is equal to itself. 3) two multiply two or more numbers with the same base, simply add the exponents. 4) to divide two or more numbers with the same base simply subtract the exponents.
Exponent rules
400
is a number where the base is 10
power of 10
401
one tenth of a bel=
Decibel
402
is the unit for expressing in logarithmic terms, the ratio between two power levels
Bel
403
with the 10 log function each double in value is equal to 3.01db increase, while -3.01 divides the value in half
know this rule
404
an absolute level that describes the amount of signal at a specific location in the system.
dBmV
405
10log=
wattage
406
20 log=
voltages
407
0dBmV=
1mV
408
each 6dB change either doubles or halves the voltage, and each 20dB change affects the voltage by a factor of ten
know this rule
409
a discontinuous signal whose various states are discrete intervals apart
digital signal
410
used to convert an analog signal to a digital signal
Digitizer
411
are a continuous signal or carrier that varies in amplitude or frequency
analog signals
412
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
413
a set of bits that represent a single character. usually there are eight bits in a
Byte
414
the number of changed states that can occur per second
Baud
415
advantage of analog transmissions are
1) no conversion necessary for human recognition 2) economical over short distances (up to 25miles)
416
disadvantages of analog transmission are
1) added distortion and noise when employing amplification. 2) electrical interference modulating the waveform. 3) limited distance for acceptable performance.
417
digital conversion consists of
sampling, quantization, and encoding
418
is the measuring of the analog signal at specific intervals
Sampling
419
is the assigning of a specific value to each of the samples
Quantization
420
is the process by which these values are converted into a data or bit stream
Encoding
421
can interfere with an analog signal and reduce its clarity
thermal or interfering noise
422
is synchronized with that of the transmitter so its available to read the digital sample when it arrives
digital receiver or regenerator
423
are regenerated rather than amplified
Digital bits
424
is the means of superimposing sound on an RF carrier
AM
425
is the means of superimposing sound on an RF carrier of a particular frequency
FM
426
3 different types of modulation in analog
Amplitude(AM),Frequency(FM), and Phase(PM)
427
five most common modulation schemes are
1)Amplitude shift keying(ASK) 2) Frequency shift keying(FSK). 3) Phase shift keying(PSK). 4) Quadrature phase shift keying(QPSK). 5) Quadrature amplitude modulation(QAM)
428
frequency and phase of the signal carrier are constant. amplitude is varied
Amplitude shit keying(ASK)
429
amplitude and phase of the signal are constant. frequency is varied. used in pathrak telemetries
Frequency is varied (FSK)
430
amplitude and frequency are constant. phase is varied.
Phase shift keying (PSK)
431
defined as the position on a waveform cycle at a specific point in time. on cycle is defined as 360 degrees of phase
Phase
432
the two most common digital modulation schemes that use a combination of changes are
QPSK and QAM
433
unwanted sum of and difference in frequencies resulting from the heterodyning of two or more signals
Beat
434
are caused when an analog TV signal arrives at a receiver just before or after the desired TV signal
Ghost
435
caused when the same channel from two or more different TV stations is received by the same antenna
co channel interference
436
caused by power line arcing, lightning, electrical motors, automobile ignition, and other sources of high rise time energy entering the cable system from the tap up to and including the TV receiver
Electrical interference
437
ingress from transmitters operating in the upstream frequency bandwith
return path interference
438
often caused by poorly made or corroded connectors ,it actually changes the shape of the RF wave from(disimilar metals)
common path distortion (CPD)
439
what causes CPD
when two or more carries encounter a non linear device, such as a connection where oxidation has occurred, harmonics and difference are produced
440
a chemical change caused by a reaction to oxygen, such as rust
Oxidation
441
a component frequency of the signal that is an integer multiple of the fundamental frequency.(twice whatever original frequency is)
Harmonics
442
the amount of noise an amp adds
noise figure
443
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
444
a theoretical temperature equivalent to the absolute absence of heat and equal to -273.15 degrees C, -459.67F, or zero degrees Kelvin
absolute zero
445
change in termination noise amounts to approximately .17dB per 20 degree fahrenheit change in temperature
know this rule
446
C/N Rules
Rule 1) if the input level numerically equals an amplifiers NF, the output ratio will always be 59.2dB. Rule 2) for each dB when the input level is raised above the amplifiers NF, the output ratio improves by an equal amount above 59.2. Rule3) C/N ratio at the output of a single amplifier is always worse than that at the input an amount equal to the amplifiers NF
447
log uses
10logN for C/N, 12 logN for composite second order (CSO), and 20 logN for Xmod and CTB
448
undesired change in the waveform of a signal
distortions
449
the second harmonic products of any two channels are typically 6dB below the level of the sum and difference products
Discrete second order
450
the combination of the amplitude and the logarithmic sum of the number of beats that fall in a channel determine the level of interference
composite second order
451
when a carrier is applied to an amplifier, it will produce the second order beats and will produced third order products as well
discrete third order
452
as each carrier is added to the system , it interacts with all the other carriers producing more and more second and third order beats.
composite third order
453
C/CTB follows a 20log relationship, and each dB raise in the levels of an amplifier, the carrier to CTB gets worse by two dB
know this rule
454
adding two devices with the same C/CTB ratios degrades the result by 6dB
know this rule
455
the crossing of modulation from one channel to another. typically manifests itself as a vertical bar in the viewed picture
cross modulation(XMOD)
456
this is a third order product and follows a 20log function for every dB that the levels of an amplifier are raised the carrier to cross mod ratio gets 2db worse
know this rule
457
doubling the number of channels carried degrades this ratio by 6dB and so does doubling the cascade
know this rule
458
appears as horizontal bars in the picture . a primary source is the power passing chokes or capacitor leak in passive devices.
Hum modulation
459
amplifier circuit paths that allow AC voltage to be directed onto specific cables
Power passing chokes
460
hum modulation is a low frequency signal, which the FCC states must be less than 3% of the video carrier level
Hum modulation Test
461
are the two basic parameters used to evaluate the quality and performance of the digital signals
MER and BER
462
is defined as the ratio of the number of wrong bits over the number of total bits
Ber
463
is typically an overload effect noted through digital signal processing equipment. this is an overdrive, or over modulation of the single carrier
Spectral re growth
464
an international telecommunications standard that permits the addition of high speed data transfer to an existing CATV system
DOCSIS
465
generates light in the transmitter
Laser Diode
466
is a family of standards for compressing decompressing A/V in a digital format
MPEG
467
advantages of MPEG are
remove redundant info without losing quality while saving bandwith
468
MPEG1
video CD
469
MPEG2
HDTV/DVD
470
MPEG4
streaming video
471
has all the spatial info
I picture
472
use both past and subsequent pictures
B picture
473
is calculated by comparing previous and successive picture
P picture
474
a cable version of CDMA , a cell phone technology that allows many users to access the network at the same time
SCDMA
475
provides the ability to control latency
QOS
476
how many channels can u bond with docsis 3.0
4 or 8 down 4 up
477
number of timeouts caused by the cmts not receiving a response within aspecified time from the cmts to a ranging request. upstream errors
T3
478
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
479
the operational settings for the cable modem
Boot file
480
a series of Reed -Solomon symbols forms the codeword. it s a series of values that conforms to a known pattern.
codewords
481
when there are more than___ errored symbols in a codeword the entire codeword is errored
3
482
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
483
method for transferring data across the network
Trivial file transfer protocol (TFTP)
484
assigns time slots for when modems can speak. configured in the CMTS
TDMA
485
instead of a time slot, the modem gets a code for all the data it is sending
SCDMA
486
is a set of rules that govern how devices transport data
Protocol
487
allows interoperability of devices from different vendors
protocols
488
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)
489
used to transport voice and video media
Real Time Transport Protocol (RTP)
490
unlike tcp/ip it has no error correction
Universal Datagram Protocol (UDP)
491
UTP
unshielded twisted pair
492
has a field of 32 bits and dotted decimal
ipv4
493
written in colon hexidecimal format and uses numbers and letters
ipv6
494
can be configured for ipv4only or ipv6only
singlestacked device
495
can be configured fro both ipv4 or 6
dual stacked device
496
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
497
What component is known as the brain of the cable system?
Headend
498
What are the signals that are used to pass channels to the customer?
Analog and Digital
499
Any device which does not require electricity to perform its function?
Passive Device
500
Any device which requires electricity to perform its function?
Active Device
