SCTE Broadband Distribution Specialist (BDS)
Certification Exam | Complete QUESTION Bank, Most
Tested QUESTIONs & Verified Answers
QUESTION 1
What is the primary principle of unity gain in a coaxial distribution
amplifier cascade?
• A. The gain of each amplifier exactly equals the signal loss of the
preceding section of coaxial cable at a specified pilot frequency,
keeping output levels constant throughout the cascade.
• B. All downstream channels are boosted to exactly 100 dBmV to
overcome terminal resistance.
• C. The upstream return path power is maintained at zero dBmV
across all customer drops.
• D. AC commercial power is equalized evenly between active
amplifiers and power supplies.
Correct Answer: A. The gain of each amplifier exactly equals the signal
loss of the preceding section of coaxial cable at a specified pilot
frequency, keeping output levels constant throughout the cascade.
Detailed Rationale: Unity gain ensures that as RF signals travel through
cable spans (where they lose power) and amplifiers (where they gain
power), the net signal level at the output of each amplifier remains
consistent, preventing excessive buildup of noise or distortion.
,QUESTION 2
What does the Velocity of Propagation (VoP) specify for a coaxial
cable?
• A. The physical breaking strength of the messenger wire under
tension.
• B. The speed at which an RF wave travels through the coaxial
cable relative to the speed of light in a vacuum, expressed as a
percentage.
• C. The maximum DC current rating of the center conductor.
• D. The rate at which connector insertion loss degrades over
temperature swings.
Correct Answer: B. The speed at which an RF wave travels through the
coaxial cable relative to the speed of light in a vacuum, expressed as a
percentage.
Detailed Rationale: VoP (typically around 85% to 88% for foam
polyethylene dielectric hardline cables) is an essential parameter used
by Time Domain Reflectometers (TDRs) to accurately measure distance
to faults or cable lengths.
QUESTION 3
What is the primary function of a power inserter in a hybrid fiber-
coaxial (HFC) distribution network?
• A. To convert digital data packets into analog QAM carriers.
• B. To couple AC standby power onto the coaxial cable's center
conductor to power remote active devices (amplifiers and optical
, nodes) while allowing RF signals to pass through with minimal
insertion loss.
• C. To split downstream broadband signals into multiple equal
customer drops.
• D. To terminate unused distribution ports with 75-ohm resistors.
Correct Answer: B. To couple AC standby power onto the coaxial cable's
center conductor to power remote active devices (amplifiers and optical
nodes) while allowing RF signals to pass through with minimal insertion
loss.
Detailed Rationale: Power inserters allow AC power from outdoor
power supplies to be injected into the coaxial hardline network to
energize active electronics along the distribution plant without
interrupting RF signal flow.
QUESTION 4
How does the attenuation of a hardline coaxial cable change as the
operating RF frequency increases?
• A. Attenuation decreases significantly at higher frequencies.
• B. Attenuation remains perfectly flat across all frequencies.
• C. Attenuation increases as frequency increases, meaning high
frequencies suffer greater loss over distance than low frequencies.
• D. Attenuation drops to zero above 500 MHz.
Correct Answer: C. Attenuation increases as frequency increases,
meaning high frequencies suffer greater loss over distance than low
frequencies.
, Detailed Rationale: Coaxial cable attenuation is proportional to the
square root of frequency due to skin effect and dielectric losses,
creating a natural high-frequency tilt that requires equalization.
QUESTION 5
What is the operational difference between a directional coupler and a
line splitter in a coaxial distribution network?
• A. A line splitter divides the input RF signal equally into two or
more output ports, whereas a directional coupler splits the power
unequally, providing a low-loss main feeder path and a high-loss
tapped output.
• B. Directional couplers carry AC power only, while line splitters
carry digital data only.
• C. Line splitters are used exclusively inside fiber nodes, whereas
directional couplers are used only inside customer homes.
• D. There is no technical difference between the two devices.
Correct Answer: A. A line splitter divides the input RF signal equally into
two or more output ports, whereas a directional coupler splits the
power unequally, providing a low-loss main feeder path and a high-loss
tapped output.
Detailed Rationale: Directional couplers allow operators to pull off a
specific fraction of power to feed branch lines while keeping insertion
loss on the main trunk line minimal, whereas splitters divide power
evenly.
QUESTION 6
Certification Exam | Complete QUESTION Bank, Most
Tested QUESTIONs & Verified Answers
QUESTION 1
What is the primary principle of unity gain in a coaxial distribution
amplifier cascade?
• A. The gain of each amplifier exactly equals the signal loss of the
preceding section of coaxial cable at a specified pilot frequency,
keeping output levels constant throughout the cascade.
• B. All downstream channels are boosted to exactly 100 dBmV to
overcome terminal resistance.
• C. The upstream return path power is maintained at zero dBmV
across all customer drops.
• D. AC commercial power is equalized evenly between active
amplifiers and power supplies.
Correct Answer: A. The gain of each amplifier exactly equals the signal
loss of the preceding section of coaxial cable at a specified pilot
frequency, keeping output levels constant throughout the cascade.
Detailed Rationale: Unity gain ensures that as RF signals travel through
cable spans (where they lose power) and amplifiers (where they gain
power), the net signal level at the output of each amplifier remains
consistent, preventing excessive buildup of noise or distortion.
,QUESTION 2
What does the Velocity of Propagation (VoP) specify for a coaxial
cable?
• A. The physical breaking strength of the messenger wire under
tension.
• B. The speed at which an RF wave travels through the coaxial
cable relative to the speed of light in a vacuum, expressed as a
percentage.
• C. The maximum DC current rating of the center conductor.
• D. The rate at which connector insertion loss degrades over
temperature swings.
Correct Answer: B. The speed at which an RF wave travels through the
coaxial cable relative to the speed of light in a vacuum, expressed as a
percentage.
Detailed Rationale: VoP (typically around 85% to 88% for foam
polyethylene dielectric hardline cables) is an essential parameter used
by Time Domain Reflectometers (TDRs) to accurately measure distance
to faults or cable lengths.
QUESTION 3
What is the primary function of a power inserter in a hybrid fiber-
coaxial (HFC) distribution network?
• A. To convert digital data packets into analog QAM carriers.
• B. To couple AC standby power onto the coaxial cable's center
conductor to power remote active devices (amplifiers and optical
, nodes) while allowing RF signals to pass through with minimal
insertion loss.
• C. To split downstream broadband signals into multiple equal
customer drops.
• D. To terminate unused distribution ports with 75-ohm resistors.
Correct Answer: B. To couple AC standby power onto the coaxial cable's
center conductor to power remote active devices (amplifiers and optical
nodes) while allowing RF signals to pass through with minimal insertion
loss.
Detailed Rationale: Power inserters allow AC power from outdoor
power supplies to be injected into the coaxial hardline network to
energize active electronics along the distribution plant without
interrupting RF signal flow.
QUESTION 4
How does the attenuation of a hardline coaxial cable change as the
operating RF frequency increases?
• A. Attenuation decreases significantly at higher frequencies.
• B. Attenuation remains perfectly flat across all frequencies.
• C. Attenuation increases as frequency increases, meaning high
frequencies suffer greater loss over distance than low frequencies.
• D. Attenuation drops to zero above 500 MHz.
Correct Answer: C. Attenuation increases as frequency increases,
meaning high frequencies suffer greater loss over distance than low
frequencies.
, Detailed Rationale: Coaxial cable attenuation is proportional to the
square root of frequency due to skin effect and dielectric losses,
creating a natural high-frequency tilt that requires equalization.
QUESTION 5
What is the operational difference between a directional coupler and a
line splitter in a coaxial distribution network?
• A. A line splitter divides the input RF signal equally into two or
more output ports, whereas a directional coupler splits the power
unequally, providing a low-loss main feeder path and a high-loss
tapped output.
• B. Directional couplers carry AC power only, while line splitters
carry digital data only.
• C. Line splitters are used exclusively inside fiber nodes, whereas
directional couplers are used only inside customer homes.
• D. There is no technical difference between the two devices.
Correct Answer: A. A line splitter divides the input RF signal equally into
two or more output ports, whereas a directional coupler splits the
power unequally, providing a low-loss main feeder path and a high-loss
tapped output.
Detailed Rationale: Directional couplers allow operators to pull off a
specific fraction of power to feed branch lines while keeping insertion
loss on the main trunk line minimal, whereas splitters divide power
evenly.
QUESTION 6
