RF for RX & TX levels are within spec @ amp input but no RF at all amp outputs. Next step is?

Test to ensure amplifier is powered

Wheres problem? RG6 loss=1dB/100'@30MHz. Tap to GB=150'. Interior= 51'. Tap=42. GB=48. CPE= 53.

Both interior and exterior cables have problems, Only Exterior Line has a problem

A TC about incoming calls failing to ring is found/fixed behind wall plate. What is next step?

Check all other phones for proper functionality

During a DOCSIS test, the SLM's modem performs "ranging" w/the _____, just like sub's modem.

CMTS (Cable Modem Termination System)

A modem's LED lights are all dark. What is the next step in the troubleshooting process?

Check to see if modem's power cord is securely plugged in

How many errors does 1.5E-08 represent when not in scientific notation & negative exponents?

15 errored bits for every 1,000,000,000 bits received

What tool is best for measuring ingress in the return path at a splitter?

Spectrum Analyzer (Ingress Scan)

What should you do to make sure your leakage meter is working properly?

Regularly reference the meter against a calibrated leak.

How many errors does 1.2E-02 represent when not in scientific notation & negative exponents?

12 errored bits for every 1,000 bits

How can a tech learn how another provider configured the residence’s phone wiring network?

Make observations at Telco NID noting colors and connections

Tech verifies good RX/TX at GB/splitter but bad RX/TX at modem wallplate. What step is next?

Repair/replace interior wire between splitter & modem outlet

If ingress is present, can ingress be measured at either end of the drop cable?

Ingress affects RX and TX and can be measured at either end.

Which of the following 3 would contribute to a poor MER?

Noise, Distortion, Impedance Mismatches

What answer addresses something important to do in the "Verify" step in the troubleshoot model?

Ask sub if all services are working to their satisfaction

TV w/intermittent macroblocking. SLM measures 1.0E-9 post-BER & 3.5E-6 pre BER What is Problem?

Poor quality RF at the wall plate, needs troubleshooting

Which answer lists common uses for a Digital Multimeter (DMM)?

Measuring electrical resistance and AC or DC voltages

No VOD services working. Meter = no upstream connectivity at wallplate & GB. What to do next?

Test the upstream at the tap port

Which statement regarding modulation error ratio (MER) is TRUE?

Good MER readings are 3 to 6 dBmV above the lower threshold

How many errors does 1.0E-05 represent when not in scientific notation & negative exponents?

10 errored bits for every 1,000,000 bits received

What 3 questions are appropriate to ask during the "Analyze" step in the Troubleshooting Model?

Prob w/ TV/Internet?Added new phone/FAX?# of phone affected?

An ingress spike of -11.0 dBmV is measured when connected to customers drop. What's this mean?

A major problem exists in drop system and needs fixing asap

Sub reports "no pic" @ primary TV. What is next best step to begin troubleshooting blue screen?

Ask sub if other TVs connected to cable in home

What statement regarding quadrature amplitude modulation (QAM) is TRUE?

QAM uses 2 carriers, same frequency, out of phase 90 degrees

How can the tech isolate the eMTA from the subs wiring system to test dial tone?

Connect test phone into eMTA port Line 1 to test dial tone

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Advanced Troubleshooting

104 termsStudBud Administration1,225 plays

Troubleshooting Skills for Beginning Installers

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Questions 104

Answers

1
When addressing Internet speed complaints, run a speed test using which connection type?
Single Phase Wire
Ethernet wired
Flexible Strand
Cat 3 Voice
2
RF for RX & TX levels are within spec @ amp input but no RF at all amp outputs. Next step is?
Look for hum bars on the primary TV
Replace all F Connectors at ISA (amp)
Troubleshoot the RX side of the drop system
Test to ensure amplifier is powered
3
A non-scrambled analog channel is needed to check for________. (channel typically in low band)
Blocking and Tiling
Flapping
MER
Hum
4
What test equipment can be used to determine where a cable is buried and its depth?
QAM Analyzer
Signal Level Meter (SLM)
Time-Domain Reflectometer
Cable Locator
5
Original information/signal before it's modulated for transmission or removed from a carrier.
Baseband
Longband
A-band
Widecast
6
Wheres problem? RG6 loss=1dB/100'@30MHz. Tap to GB=150'. Interior= 51'. Tap=42. GB=48. CPE= 53.
Both interior and exterior cables have problems
Only Exterior Line has a problem
Problem in Feeder System
Only Interior line has a problem
7
A leak is completed if level of _____ µV/m at 3 meters or 10' is measured from CATV equipment.
100
-50
0
50
8
A TC about incoming calls failing to ring is found/fixed behind wall plate. What is next step?
Check all other phones for proper functionality
Try to upsell the customer
Conclude the trouble call
Educate customer about corrosion on the lines
9
During a DOCSIS test, the SLM's modem performs "ranging" w/the _____, just like sub's modem.
CMTS (Cable Modem Termination System)
FEC (Forward Error Corrector)
eMTA (embedded Multimedia Terminal Adaptor)
ILEC (Incumbent Local Exchange Carrier)
10
How does multimeter express resistance with metric prefix/ohms symbol if measures 0.0023 ohms?
230.00 mΩ
23.0 mΩ
.023 mΩ
2.30 mΩ
11
What questions elicit a lengthier response to elaborate on issues a customer is experiencing.
Open ended
Pointed
Closed ended
Perplexing
12
When temperature decreases from 60 degrees to 10 degrees will attenuation increase or decrease?
Attenuation remains unchanged
Attenuation decreases
Attenuation Increases
Attenuation stays the Same
13
What is the goal for forward RF levels at a cable modem?
-12 dBmV to +12 dBmV
120 VDC +/- 5 volts
above 35 dB
below -50 MHz
14
A modem's LED lights are all dark. What is the next step in the troubleshooting process?
Check to see if modem's power cord is securely plugged in
Measure downstream RF levels at the tap port
Check cable connections at the bonding block
Measure the upstream transmit level at the splitter
15
What unit is an absolute measurement expressing signal strength?
decibel (dB)
decibel millivolt (dBmV)
16
How many errors does 1.5E-08 represent when not in scientific notation & negative exponents?
150 errored bits for every 100,000,000 bits received
15 errored bits for every 1,000,000,000 bits received
17
What is a 6MHz wide carrier with modulation scheme providing operational data rate of 38Mbps?
256 QAM
26 MER
64 QAM
1.0E-8 BER
18
What is it called when one of the two conductors in a pair is broken in two?
reverse polarity
a short
normal polarity
an open
19
If CATV carriers at 108-137 MHz or 225-406 MHz leak out, what off-air signals can be disrupted?
Baby Monitor
Wi-Fi - 802.11a
Aircraft Communications
Cordless Phones
20
What tool is best for measuring ingress in the return path at a splitter?
Time Domain Reflectometer (TDR)
Digital Multimeter (DMM)
Cable Locator
Spectrum Analyzer (Ingress Scan)
21
Video is AM, Audio is FM, Phase modulation controls color. What is being described?
Analog television channel
ADSG converter
A 64 QAM carrier
Motion Picture Expert Group Standard
22
What should you do to make sure your leakage meter is working properly?
Manually adjust the tuning knob on the back of meter.
Call manufacturer quarterly & request calibration numbers.
Make your meter to look like another techs with good numbers
Regularly reference the meter against a calibrated leak.
23
Order of operations in math is PEMDAS; Parenthesis, Exponents, ________, Divide, Add, Subtract
Multi-functional
Marinate
Multiply
Mutate
24
How many errors does 1.2E-02 represent when not in scientific notation & negative exponents?
12 errored bits for every 1,000 bits
1200 errored bits for every 100 bits
25
Multiple outlets have no signal. RX & TX levels are within spec at GB. What is next step?
Locate and test the splitter
Replace the connectors behind each wall plate
Locate and test the tap
Replace the converters at the residence
26
How can a tech learn how another provider configured the residence’s phone wiring network?
Connector Locator to NID
Make observations at Telco NID noting colors and connections
Ask the customer to explain the wiring to them
Contact Telco Voice Support Team
27
Tech verifies good RX/TX at GB/splitter but bad RX/TX at modem wallplate. What step is next?
Repair/replace interior wire between splitter & modem outlet
Test forward and return connectivity at tap
Repair/replace exterior wire between tap and ground block
Replace the splitter
28
If ingress is present, can ingress be measured at either end of the drop cable?
Ingress affects RX and TX and can be measured at either end.
It only affects RX and can only be measured at splitter.
If high freq problem it can't be measured at either end.
It only affects TX and can only be measured at tap.
29
Two black bars are on customer's video display. What setting could help remove them?
Aspect Ratio
Sleep Mode
Purchase Pin
Closed Caption Settings
30
What devices generate RF interference at 2.4GHz and 5GHz ranges that might cause WiFi issues?
AM/FM Radio Alarm Clocks
TV Remote Controls
USB Webcams
Bluetooth Devices
31
Which of the following 3 would contribute to a poor MER?
Insulation, Lightning, Thunder
Tight F Connections
UFO, EFO, VHF
Noise, Distortion, Impedance Mismatches
32
What answer addresses something important to do in the "Verify" step in the troubleshoot model?
Ask sub if all services are working to their satisfaction
Bypass the suspected portion to see if the problem clears up
Eliminate sections of cable plant as part of the problem
Ask the sub when they first noticed the problem happening
33
What unit is relative measurement expressing signal loss/gain, not measure of signal strength?
decibel (dB)
decibel millivolt (dBmV)
34
When using ingress scan to check shielding integrity at splitter Input, what should meter show?
Ingress under the carrier at -10 dBc
Noise floor below -40 dBmV
Jitter at 15 ms or higher
0 dB sine wave
35
What unit of measure identifies intensity of electromagnetic field produced by signal leaks
Ohms
Microvolts per Meter
dBmV
Error Vector Enumerator
36
TV w/intermittent macroblocking. SLM measures 1.0E-9 post-BER & 3.5E-6 pre BER What is Problem?
Problem with SLM-send back to manufacturer
Poor quality RF at the wall plate, needs troubleshooting
Set-top box needs to be swapped
Customer’s HDTV settings are misaligned
37
Which answer lists common uses for a Digital Multimeter (DMM)?
Locating RF leakage and measuring its strength
Identifying the path an UG wire takes between two points
Detecting RF carrier levels at specific frequencies
Measuring electrical resistance and AC or DC voltages
38
No VOD services working. Meter = no upstream connectivity at wallplate & GB. What to do next?
Replace the splitter in the basement
Tone all the outlets out and tag the lines
Replace the converter box
Test the upstream at the tap port
39
Electrical Appliances, CB's, Light Ballasts, Smart Phone using 4G LTE are common sources of___.
Bonding
Distortion
Leakage
Intermittent Ingress
40
At the customer's wall plate, the goal for bit error rate (BER) is_______ on Pre and Post.
1.00E-09
20 microvolts at 10 feet
0 dBmV at CPE
32
41
Which statement regarding modulation error ratio (MER) is TRUE?
The upper MER threshold for 256 QAM is 26 dBmV
With MER readings, lower number = better quality signal
The lower MER threshold for 256 QAM is 55 dB
Good MER readings are 3 to 6 dBmV above the lower threshold
42
How many errors does 1.0E-05 represent when not in scientific notation & negative exponents?
10 errored bits for every 1,000,000 bits received
100 errored bits for every 100,000 bits received
43
What is minimum MER level for a healthy 256-QAM carrier at the customer premises equipment?
35 dB
1.0E-09 Pre
18 dB
3.0E-06 Post
44
What's transmit level @tap? RG-11 =240' and loses .75 dB/100'@ 30MHz. Transmit @ GB= 35.2 dBmV.
55.9 dBmV
30.3 dBmV
25.8 dBmV
33.4 dBmV
45
What 3 questions are appropriate to ask during the "Analyze" step in the Troubleshooting Model?
Is CPU Current?Got Cable?Want Internet?
Prob w/ TV/Internet?Added new phone/FAX?# of phone affected?
Prob w/Closed captions?Added VOD?# of service calls in past?
Got a ladder?Have a flashlight?Want 1Gig down?
46
An ingress spike of -11.0 dBmV is measured when connected to customers drop. What's this mean?
Check the frequency, it may be a harmless problem.
A minor issue in drop system and won't cause a problem.
Check what services customer has, if video, then no problem.
A major problem exists in drop system and needs fixing asap
47
Sub reports "no pic" @ primary TV. What is next best step to begin troubleshooting blue screen?
Repair TV's tuner or advise sub of reputable repair facility
Tone all the lines out to make sure you get a strong tone
Ask sub if other TVs connected to cable in home
Use the Digital Multimeter (DMM) to test for hum
48
Select the answer that puts the 4 steps of the troubleshooting model in correct order, 1-4.
Analyze, Isolate, Fix, Verify
Isolate, Fix, Verify, Analyze
Fix, Verify, Analyze, Isolate
Analyze, Isolate, Verify, Fix
49
What statement regarding quadrature amplitude modulation (QAM) is TRUE?
QAM uses 2 carriers, same frequency, out of phase 90 degrees
QAM is a security protocol through use of security keys
QAM can impress data onto a carrier by varying freq of wave
QAM is a national standard for compressing video
50
Which windows command is used to view the IP address of a computer?
tracert
ipconfig
ping
listserv
51
How can the tech isolate the eMTA from the subs wiring system to test dial tone?
Unplug the eMTA power cord
Connect test phone into eMTA port Line 1 to test dial tone
Connect station wire from line 1 to line 2
Connect the SLM to port 1 of eMTA
52
What utility does the technician use to check for latency with a particular website?
continuous trace
continuous researcher
continuous ping
continuous IP
53
If RG-6 has loss of 4.65 dB/100' @550 MHz, what is acceptable loss across 150'?
15.0 dB
10.0 dB
3.5 dB
7.0 dB
54
Forward RF is below spec @ wall plate but above spec @ GB. What should be done next?
Calculate the loss between (GB) ground block and wall plate
Connect a pad to the cable at the wall plate
Replace all cable in the house until the problem goes away
Tone out the exterior drop cable
55
What is Charter standard for MER and BER at the tap for a 256-QAM carrier?
MER greater than 45 dB with Pre and Post BER of 9.0E-2
MER less than 25 dBmV with Pre and Post BER of 3.5E-7
MER at least than 1.0E-9 with Pre and Post BER of 35 dB
MER 35 dBmV or greater with Pre and Post BER of 1.0E-9
56
Customer has intermittent macroblocking on one channel but its ok today. How to troubleshoot?
Test RCA connections for reflections
Perform a DOCSIS test
Check for ingress in the house drop system
Test the lowest analog carrier to see if it fluctuates
57
Transmit @ GB 36.25 dBmV. 65' RG6 & 4way between GB & wallplate. (1.17dBper100')&splitter -7.0
55 dBmV at wall plate
37 dBmV at wallplate
44.0 dBmV at wallplate
-28 dBmV at wall plate
58
What is the goal for RF transmit levels at a cable modem?
+20 dBmV to +35 dBmV
+50 dBmV to +65 dBmV
below 20 dBmV
+35 dBmV to +50 dBmV
59
Meter detects Ingress in sub-low at splitter input. Which is likely source of ingress?
Defective router
A loose connector at set-top box
A cut drop between house and pole
Bad connector at tap
60
Why does signal strength increase and attenuation decrease when temperature goes down?
Joules Law
Theory of Relativity
Cable contracts in the cold causing less attenuation
Cable expands in the cold causing stronger signal
61
What is tested when the technician pings the default gateway?
The connection between the computer and the tap
The connection between the computer and the router
The connection between the computer an the speedtest server
The connection between the computer and the node
62
When the customer is hearing part of a voice conversation from another circuit is known as?
short
cross talk
echo
open
63
What is Hum Modulation?
Problems with the OFDM Modulation
Distortion of carriers by a 60 Hz or 120 Hz voltage
Ingress from an outside source
MPEG 2 Compression gone bad
64
Which statement about the RJ-31X is True?
Replacing RJ-31X is a step in the Voice Services TS process
RJ-31X must be removed to avoid seizure
RJ-31X is installed/maintained by an alarm service provider
RJ-31X will perform line seizure if RJ45 plug is removed
65
Which statement about polarity reversal (rolled polarity) is True?
Polarity reversal is no longer a problem
Fax machines require polarity reversal
Polarity reversal issues should be corrected as encountered
Phone requiring .5 REN will require polarity reversal switch
66
What answer is something important to do during the Analyze step in the troubleshooting model?
Install an amp because amps fix everything
Apply the TALK method
Perform the procrastinate technique
Ask questions
67
Which term refers to the ratio of errors to the total amount of data sent?
Latency
RCA Band
Bit Error Rate
MOS Score
68
Spectrum Internet Service requires a ____________ RF communication path.
Two way
one way
upper
lower
69
What is forward error correction (FEC)?
Its how to fix Hum Problems at 60 or 120 Hz
Additional data added to a digital payload to correct errors
Another way to express BER problems
Type of modulation to add 8 - 10 channels to QAM
70
Describe a shielded network where RF carriers are traveling inside of cables.
An exposed system
An open system
A closed system
A renewable system
71
Loss of signal quality in Analog can be _____ but in digital modulation, it can be ______.
Sudden, Gradual
Gradual, Sudden
72
Where can tech direct Sub if they have additional questions about Spectrum Voice services?
411
311
711
611
73
Which of the following is commonly used by the technician to verify set-top box operation?
Testifier
On-Screen Diagnostics
Cable Locator
Cable Toner
74
What modem is no longer supported & should be replaced with modem from recommended modems list?
QAM 256
ARRIS SBG1683
DOCSIS 1.0
QAM 1024
75
If cable changes 1% every 10 degrees, then what percent does cable change over 30 degrees?
4%
3%
5%
2%
76
Which frequencies are affected when CATV signals leak out or LTE4G signals ingress into system?
The sub-band (5-48 MHz)
The 700 MHz band (698 - 806 MHz)
The AM band (525-1705 kHz)
The FM band (88-108 MHz)
77
A home run phone system has a separate line wired from a central location to each _______.
phone jack
NID
Splitter
House Enclosure
78
50' RG-59 is losing 3.5 dB at 750Mhz. How much less would RG-6 lose? (5.5 dB/100' at 750 MHz)
less than 1 dB lower than RG 59 if same length
3 dB less than RG 59 if same length
2 dB less than RG 59 if same length
4 dB less than RG 59 if same length
79
VoIP shows how well a network carries voice traffic. What 3 factors affect VoIP test results?
MOS, FEC, TDR
PAL, IRC, HRC
Jitter, Delay, Packet Loss
FVD, RIO, BUG
80
If a cable span loses 20 dB when its 20° F, what will it lose if temp (1%per10°)rises to 70°F?
19 dB
15 dB
25 dB
21 dB
81
A 310' RG-6 drop loses 18dB at 750Mhz. How much less will RG-11 lose(3.58 dB/100' at 750 MHz)?
7 dB less attenuation
2 dB less attenuation
5 dB less attenuation
10 dB less attenuation
82
What is the name of digital TV standard used to compress signal to add channels/services?
Motion Pictures Experts Group (MPEG)
Video Graphics Integrator (VGI)
Channel and Services Integration Protocol (CSIP)
Institute of Electrical & Electronics Engineers (IEEE) 1394
83
What is the best item to use when tracking a shorted phone wire pair?
Telco ILEC Switch
(SLM) Signal Level Meter
QAM Tester
Continuity Tester
84
What does the initialism CLI stand for?
Cumulative Leakage Index
Core Leakage Ingress
Conduit Leakage Interference
Cable Latitude Impress
85
What do CATV systems use to tell which cable plant is leaking when many systems in same area?
Dipole Identifier
Directional Amplifier
Channel Tagger
Near Field Probe
86
Which answer lists a common use for a Time-Domain Reflectometer (TDR)?
Measuring RF carrier levels' dBmV at specific frequencies
Prevent injuries from dangerous voltages
Locating RF leakage and measuring its signal strength
Identifying coax fault types(open/short) & distance to fault
87
Cross talk is a common issue with ___________ phone wiring.
Cat5e
Cat 6
Standard Two-Pair
Cat 7
88
Where does 256 come from in the term 256-QAM?
8 bits per symbol and 2 raised to the 8th power equals 256
6 bits per symbol and 2 raised to the 6th power equals 256
256 bits per symbol and 2 raised to 256th power equals 1.15E
4 bits per symbol and 2 raised to the 4th power equals 256
89
A tiling issue is isolated to a bad drop cable. You replace the drop cable. What to do next?
Test RX levels, MER/BER @ GB to verify they meet specs
Verify Video on Demand works at the primary TV
Bury the cable from tap to house box
Head to your next job because everything is fixed now
90
What measurement function of a SLM is used to check the quality of a QAM carrier?
MTA
C/N
TDR
MER
91
What is tested when the technician pings the loopback address (127.0.0.1)?
Default Gateway
Cable Modem Termination System (CMTS)
Network Interface Card (NIC)
Google
92
What color wire should connect to red wire when CAT5 is spliced to a 2 pair phone station wire?
Black
Orange-white
Blue
Green-White
93
A 125’ span of RG-6 is losing 11 dB at 750 MHz. (loss = 5.65 per 100') Is it losing too much?
Need More Information
Yes, it is attenuating too much
Its gaining signal
No, its attenuating correctly
94
Modulation varies carrier wave properties. What 3 are common properties modulation affects?
dB, dBmV, dBm
Light, Cycle, and wavelength
Amplitude, Frequency, and Phase
Hertz, Megahertz, Gigahertz
95
What household item can overcome settop box shielding causing interference to certain channels?
Wired Phones
Fax Machines
Security Cameras
4G Phones
96
What tool shows route from source to destination & uncovers latency causing network bottleneck?
Web Route
Route DMC
Net Route
Trace Route
97
What symptom does a short circuit in telephone wiring cause?
No phones will work
Dial tone on some and static on others
Calls can be made, but cannot be received
Only brand new phones will work
98
Which 3 statements regarding resetting a cable modem are True?
Unplug, let lights stabilize, plug back in, close open apps
Plug into switched outlet and flip the switch
RF must be briefly disconnected from the modem
Click the "reset to default" settings button
99
How many completed alternating cycles is an 850 MHz carrier making every second?
85
850,000,000
855,000,000,000
85,000
100
What can be tested by connecting to an interior wire at the ground block?
audio distortions
Co-channel deviation
Ingress
Color schematics due to Frequency Modulation
101
What is 0 dBmv equal to?
0 millivolts measured across 75 Ohms of impedance
1 millivolt measured across 75 ohms of impedance
10 millivolts measured across 75 ohms of impedance
.0001 millivolts measured across 75 ohms of impedance
102
What 3 questions to ask an Internet customer during Analyze step in Troubleshooting Model?
Facebook user? Google Plus user? Twitter follower?
Connected to alarm system? Using AOL? You have Cell service?
TV/phone problems?Added new software? How many pcs affected?
Long distance carrier? Use NFL network? Gamer?
103
What carries current and applies voltages between the phones and eMTA inside the residence?
RG-6 coax
A 12 gauge ground wire
Two conductors called a “Pair”
A dedicated 300Ω antenna cable
104
Which one of the following statements about the return path (TX) is TRUE?
TX is unaffected by ingress
Fixing signal leak problems hardly prevents TX path issues
Return path ingress must use a DOCSIS packet generation test
Drop system is most common entry point for TX ingress.

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