Fiber Technician I - II

How many meters of slack cable are typically used in an aerial installation?

15-25 meters.

What is the coating diameter of most outdoor single-mode fiber?

250 µm

What can be attached to the pulling line to prevent the fiber-optic cable from twisting during installation?

A break-away swivel.

When reusing a mechanical splice for acceptance testing, what happens to the splice after each fiber is tested and removed?

A small amount of index matching gel is depleted from the splice, so the gel should be replaced as required or as the manufacturer recommends.

Which of the following is true when using troubleshooting equipment to test the fiber-optic plant?

An optical power meter is used to measure the strength of light signals anywhere in a fiber system where a connection can be made.

Which of these locations is appropriate for the installation of a splice closure?

An optical splitter.

Why are the amplitude levels into an optical transmitter different between analog television and quadrature amplitude modulation (QAM) carriers?

Because analog carriers have a video sync pulse, which can be used to set amplitude. QAM carriers don't have a sync pulse; the average power of the carrier is used to adjust the QAM carrier's amplitude.

What is the purpose of buffer tubes in fiber-optic cable?

Buffer tubes protect and separate the optical fiber in smaller bundles.

What is the benefit of coarse wavelength division multiplexing (CWDM) over dense wavelength division multiplexing (DWDM)?

CWDM allows transmission via fiber-optics, twisted-pair, coax, microwave, and wireless whereas DWDM transmits only across optical fiber.

What are two critical factors for a successful installation of fiber-optic cable?

Cable pulling tension and cable bend radius.

Full-feature optical time domain reflectometers (OTDR), also known as platform OTDRs, have these as options:

Chromatic dispersion and polarization mode dispersion (PMD) module interfaces.

Which of the following is true regarding dense wavelength division multiplexing (DWDM) systems?

DWDM systems in a fiber network create the need for an additional piece of test equipment, the optical spectrum analyzer.

Which category of fiber-optic cable makes the final connection from the individual optical ports of a multiport service terminal (MST) to the subscriber in most passive optical networks (PON)?

Drop

What is one of the requirements that have been identified for next-generation access network architectures?

Expanded troubleshooting capability.

The number of rectifiers used in a DC power plant design

Is dependent upon the load placed on the system.

Why are factory-built pigtails spliced to the optical fiber going to the patch panel instead of installing optical connectors directly to the single-mode fiber (SMF)?

It is easier and faster to splice factory-built pigtails to the optical fiber than to install optical connectors due to the tight tolerances of SMF.

Which answer best describes network topology?

It's a sub-layer of network architecture that describes the physical and logical configuration of connected elements between the signal source and the network termination elements.

What are the primary causes of intrinsic loss in single-mode fiber?

Material absorption and Rayleigh scattering.

Eliminating pulling lines using high air speed blowing (HASB) can achieve how much of a cost savings over conventional pulling techniques?

More than 40%.

What are the factors that contribute to an optical receiver's sensitivity?

Noise, responsivity, response time, linear response, back reflection, and optical detector material.

What happens if the optical signal exceeds the maximum specified input power into a photodetector?

Nonlinear operation resulting in thermal noise, shot noise, and signal loss.

Which element of an optical receiver couples the light waves from an optical fiber directly to the optical detector?

Optical interface.

Which of the following is true regarding optical power?

Optical power levels can be checked unobtrusively by simply measuring the DC voltage test point on the front of the transmitter or receiver.

Which component of an optical modulation system contains an optical detector and a demodulator?

Optical receiver.

What product based on the Data Over Cable Service Interface Specification (DOCSIS) defines the protocols for Internet protocol (IP) telephony over hybrid fiber/coax (HFC) networks?

PacketCable.

A wavelength-isolating power meter is most commonly used in

Point-to-multipoint FTTx installations.

Which of the following is true regarding referencing the light source and power meter together?

Referencing the light source and power meter together is essential prior to making field measurements.

What is a consideration for the use of ribbon fiber?

Ribbon fiber requires different tools and equipment to perform splicing.

Which category of fiber-optic cable design typically uses some variation of the star topology?

Signal distribution.

What is one process that has to happen before digital modulation can occur in an optical transmitter?

The data must be encoded.

What is one advantage and one disadvantage of single-mode fiber with a large mode field diameter (MFD)?

The larger the MFD, the easier it is to splice and connectorize the fiber, although it becomes more sensitive to bending losses.

Which of the following are features of different types of OTDRs?

The mini-OTDR was designed for field technicians and is the most common type of OTDR in use today.

What are the three functional components of an optical power meter?

The photodetector, the processing unit, and the display.

What must be considered before fiber-optic cable can be lashed over existing coaxial cable in the aerial plant?

The strand must be in good condition and have the strength to support the weight of the additional cable.

The frame structure of a synchronous transport signal (STS) is divided into two parts. What are they?

The transport overhead, which contains the section and line layers, and the synchronous payload envelope, which contains the path overhead and the payload data.

Which of the following is true regarding the troubleshooting process?

The troubleshooting process should include steps that identify, analyze, and locate the problem as well as diagnose its source, repair the problem, and test to ensure the problem is resolved.

What is true of online uninterruptible power supply (UPS) systems?

They are recommended for commercial applications such as data centers and telecommunications operations.

What should be done to work safely when working with OTDRs or other optical transmitters?

Use safety eyewear designed to protect the operator from specific wavelengths of light.