COORDINATOR I – II QUESTIONS AND
ANSWERS
Line extenders can be powered from the network or from a 120- volts alternating current (VAC)
source. Which of the following statements about line extender power sources is true?
ANSW✅✅Line extenders powered by the network can pass current to other devices.
How much intermodulation distortion degradation is added when two line extender amplifiers with
identical distortion characteristics are in cascade? ANSW✅✅6 decibels (dB).
What can cause a resistive type of test to deliver false information? ANSW✅✅An impedance
mismatch.
Why is it unnecessary to measure the unregulated direct current (DC) voltage on a line extender that
has a switching mode power supply (SMPS)? ANSW✅✅An SMPS provides DC voltage regulation
over a wider alternating current (AC) voltage range than a linear power supply.
As the RF signal travels on the coaxial cable, one portion of the signal may be attenuated more than
the others. What term is used to describe a situation where cable attenuation is low, causing signal
levels to remain greater at the higher frequencies than at the lower frequencies?
ANSW✅✅Positive tilt.
When setting up the forward amplifier of a line extender, why must the manual gain control be at a
mid-range position at the desired operating level? ANSW✅✅For the automatic/thermal control to
work effectively.
Why is it a good practice to measure the downstream input signal and compare the measurements
to the calculated levels shown on the network maps before attempting to set up the forward
amplifier section of a line extender? ANSW✅✅Undocumented changes to the network design can
affect the designed input to the line extender, or there could be a separate problem that needs to be
corrected.
A return path sweep-and-alignment system is used to adjust which of the following?
ANSW✅✅Signals from a line extender to the headend.
, When aligning amplifiers in the return path, what must be achieved and maintained from the
customer premises to the headend, or node? ANSW✅✅Unity gain
What is a metallic time domain reflectometer (MTDR)? ANSW✅✅A test instrument that measures
reflected voltage at discrete moments in time to evaluate the electrical characteristics of metallic
cables.
How does a time domain reflectometer (TDR) measure the distance to a reflection from a fault or
the end of a cable? ANSW✅✅Circuitry within the TDR converts the pulse travel time into distance
and displays the information as a waveform with a scale showing the distance to the reflection.
Velocity of propagation (VOP) is the speed of the radio frequency (RF) signals traveling in a coaxial
cable relative to the speed of light. What is the range of VOP factors for broadband coaxial cable?
ANSW✅✅0.78 to 0.93
What presents the biggest electrical shock hazard when operating a time domain reflectometer
(TDR) in the network? ANSW✅✅The low-frequency alternating current (AC) voltage on the
coaxial cable.
What does the decibel return loss (dBRL) displayed on most time domain reflectometers (TDR)
indicate? ANSW✅✅The relative severity of a cable fault.
Anomalies, such as echoes and blind spots, can hide cable faults or cause a technician to
misinterpret the signature of a time domain reflectometer (TDR) waveform. What causes an echo on
a waveform TDR? ANSW✅✅The extra distance that the TDR pulse travels after initially reflecting
off the end of the cable span.
What type of adapter provides a clean transition from the hardline coaxial cable to an F-connector
when testing hardline coaxial cable with a time domain reflectometer (TDR)? ANSW✅✅The
hardline cable-to-F female (or BAFF) adapter.
How is a time domain reflectometer (TDR) used during a tap audit or when investigating a suspicious
network connection? ANSW✅✅To confirm an illegal connection of customer premises equipment
(CPE) based on the signature of the TDR waveform.