NCTI Exam I

What technologies are defined in DOCSIS 4.0 to help sustain the hybrid fiber/coax (HFC) network infrastructure for several more years?

Full Duplex DOCSIS (FDX) and Extended Spectrum DOCSIS (ESD).

When configuring the upstream return in a distribution amplifier with multiple upstream ports, the amplitude levels for which port should be adjusted first?

(NOT) The distribution amplifier port that is shared with the primary downstream port.

What is the expected DC voltage on most hybrid fiber coax (HFC) network equipment?

+24 VDC, ± 0.5 V.

How is the distribution amplifier used in a fiber node?

-Boosts the amplitude of the downstream RF signal for delivery throughout each neighborhood -Combines/amplifies the upstream RF channels returning from the neighborhoods.

What is installed in the input stage of a distribution amplifier for a flat frequency response into the input amplifier when the input signal has negative tilt?

A cable equalizer with positive slope.

In the tree-and-branch architecture, how is the downstream signal from the trunk fed to the distribution branches?

A portion of the downstream is fed to a bridger amplifier to boost the signal before being split and routed to the distribution branches.

What is spliced into the hardline coaxial cable to combine the AC power with the transported RF signal in a hybrid fiber/coax (HFC) network?

A power inserter.

What is required for checking the physical network integrity when maintaining the coaxial cable network?

Being observant and performing some minor tasks while engaged in regularly scheduled activities.

How is the AC voltage separated from the RF signal in a distribution amplifier?

By a capacitor that passes RF but blocks the low frequency 60 hertz (Hz) AC voltage which finds a low resistance path through the RF choke that blocks RF.

What term describes the frequency spectrum into an amplifier having higher amplitude at low frequencies than the high frequencies?

Negative tilt.

What is a common solution when congestion from modem activity and traffic becomes unacceptable in a hybrid fiber/coax (HFC) network?

Node splitting, the subdividing of serving areas into two or more smaller serving areas.

What value of interstage equalizer should be installed if the associated amplifier tombstone field is blank and the amplifier output slope is 7 dB?

The default factory value.

What should you be looking for when analyzing the network design maps to troubleshoot a problem?

The device common to those customers affected before traveling to make signal status checks.

How can a distribution amplifier be identified in the network or on a network design map?

The distribution amplifier has multiple downstream outputs.

When configuring the input stage of a distribution amplifier, what element values can vary from those in the amplifier tombstone, depending on the input amplitude measurements?

The input equalizer and attenuator pad values.

How can a less-experienced technician identify what non-standard symbols on the network design maps represent?

The legend at the bottom of the network design map that defines the map symbols, cable types, and amplifier data.

Why is the term "gain control" applied to amplifier gain and controls inaccurate?

The only way to vary the output of any amplifier is to adjust the amplitude level of the signal going into the amplifier.

What is the RF distribution tap value indicated on the tap face plate by a sticker or number stamped into the housing?

The signal loss between the tap downstream input port and the tap ports

What test instrument sends out a test signal and displays any reflections caused by impedance mismatches in the cable that are characteristic of cable faults?

Time domain reflectometer (TDR)

Describe an application for a distribution amplifier in a hybrid fiber/coax (HFC) network?

To maintain downstream amplitude levels to the addresses farthest from the fiber-node.

In a distribution amplifier, why is the frequency response at the input of the second output stage sloped?

To reduce intermodulation distortion levels caused by amplifying high amplitude input levels.