Various CT level questions Flashcards
Two causes for an aerial lift to cease functioning while aloft
Hydraulic lift malfunction
Inoperable upper controls
Three aerial lift operational hazards
Electrocution
Injuries from falling, equipment failure, and unstable maneuvering
Traffic lanes
Describe how the commtech’s role may contribute to a successful preventative maint. program?
Respond quickly and efficiently to restore service
perform work without degrading or interrupting service
Work toward preventative maint. rather than repair
Three main causes of aerial lift accidents?
stability problems
operator error
violating OSHA regulations
How often are vehicle maint. checks completed?
Daily, weekly, monthly, bi-monthly, and semi-annually
Once completed the FCC form 320 is kept in?
The public file
Output C/N improves by _____ for each dB the input is raised?
1dB
What are two fiber splicing methods?
Fusion
Mechanical
Hum modulation is measured in?
Percentages
Why is 16 QAM a faster modulation technique than QPSK?
Four amplitude levels are used.
2 above and 2 below each axis
What is considered to be a ‘headend’ FCC POP test?
Differential Gain
Differential Phase
T or F The video carrier under test must be on for the CTB measurement?
False
What do you test prior to operating from the aerial lift bucket
Always test the lift controls from the ground daily and verify that all are operating properly
7 Touchstones
Diversity Respect Quality Ethics Enthusiasm Employee Focus Flexibility
What is an advantage that rebuilding a system has over an upgrade
Rebuilding increases the useable bandwidth
A reflection with the same polarity as the launch reflection indicates a(n)?
Open
What is Comcasts goal for network reliability?
4 nines / 99.99%
ICFR must be measured through a _______
Set-top-box
The _______ is the load-bearing component of an aerial hardline cable installation
Strand
What is meant by single mode?
One wavelength
Batteries should be within ____ VDC of each other
.3VDC
Which architecture offers the highest level of reliability?
Ring
Maximum length of data carrying CAT5
328’ or 100 meters
Three parts of fiber
Core
Cladding
Coating
Three criteria for positioning your aerial lift
Minimize reach
Avoid overhead obstacles
Provide safe and proper lift rotation
What material is used for doping fiber amps in the 1550nm band?
Erbium
When a loss of AC is determined to be a power company problem you should?
Contact the power company and follow your systems stand-by generator procedures
Deactivate anonymous call rejection
*87
Refractive index
Ratio of the velocity of light of two mediums of optical glass
Port-to-port isolation
The difference between the two output ports with the input port terminated
What is the cut-off freq. for a sub-split diplex filter at/around
50 Mhz
A cable with a single strength member in the center surrounded by the color coded buffer tube is known as?
Loose tube
Number of cycles of an AC waveform that occur in one second?
Frequency
What type of guy is used when strand changes direction?
Side Guy
What causes beats?
Unwanted carriers entering the system
Co-channel
Amp levels running several dB higher than specified
How much time should be added to the 3-4 second rule when towing a trailer?
2 seconds
What is the maximum variation within a 24hr adjacent channel interval?
3dB
When performing a proof-of-performance, what is the maximum variation within a 6mo interval?
8dB
Initiate call trace
*57
How many times must the 24hr level variation test be performed?
4
Why didn’t the skeleton cross the road?
He didn’t have the guts!
Calculation for Wavelength?
Freq / speed of light
Laser Classes
ANSI Standard Z-136
Class 1: Safe as long as not disassembled
Class 2/2A: Eye hazard if beam is viewed
Class 3A: Eye hazard if collected or focused on the eye
Class 3B: Eye hazard if the direct or reflected beam is viewed
Class 4: Eye and skin hazard
What is the OTDR “dead zone” and how do you overcome its effect?
The length of fiber nearest the OTDR that is affected by the recovery of the receiver from the laser test pulse.
Overcome by using a “launch fiber” sometimes called a “pulse suppressor”
4 types of AC waveforms?
Sine
Square
Quasi-square
Sawtooth
A reliability of “five nines” would allow how much downtime per year?
5.24 mins.
What is required to safely operate your aerial lift vehicle at the work site?
Properly using decals
Understand operational hazards
Utilize proper traffic controls techniques and safety equipment