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What is the difference between light and radio freq? ✔✔Light uses high freq
Radio uses short freq
What type of light is used in Fiber Optic Transmissions? ✔✔Infrared Light
What are the 4 items needed for a fiber optic system to work? ✔✔Transmitter, fiber optic cable, receiver, connectors.
1 mW is the same as what in dBM? ✔✔0 dBM
How is power measured in fiber optic ✔✔dBM
What is the best wavelength to use in fiber optic transmissions? ✔✔1550 nm
What wavelengths are most used for communications in fiber optics? ✔✔Multimode- 850 nm, 1300 nm
Singlemode- 1550 nm
When ws fiber optic cable first used for commercial telephones in the United States? ✔✔GTE 1977
When using single mode fiber optic cable what is the best light source to use? ✔✔Laser Diode (LD)
What are the two cheapest light sources used in fiber optics? ✔✔Light Emitting Diode (LED)
Vertical Cavity Surface Emitting Laser (VCSEL
All wavelengths of light travel at the same speed. True or False. Why? ✔✔False, Different freq's travel at different speeds.
Which has the larger core single mode or multimode fiber? ✔✔Multimode
The typical numerical aperture (NA) for a 50/125 um optical fiber is? ✔✔.
What measurement is used to identify loss in fiber optic cable? ✔✔dB
The path light takes along the fiber is also referred to as what? ✔✔Modes
What will happen to the strength of a fiber cable if you bend it more than is advised? ✔✔Decrease tensile strength
What is the most important requirement for making a good splice? ✔✔Precision cleaving tool
Most singlemode fiber ends are terminated onto factory made _____ and spliced to the fiber cable. ✔✔Pigtail
If a hot melt connector is cracked or not properly polished what type of loss will occur? ✔✔Extrinsic Loss
The splicing environment must be kept as ______ as possible. ✔✔Clean
Fresnel Reflection is reduced in mechanical splices by using what? ✔✔Index Matching Gel
This termination technique depends on the quality of the cleaving tool for optimum performance. ✔✔No Polish
What is the size of the ferrule on the LC connector? ✔✔1.25 mm
For a connector to be rated as good what must the repeat-ability factor be? ✔✔.75 dB
When installing cable, what is a good practice to prepare for future changes and restorations? ✔✔Slack
How often is The National Electric Code updated? ✔✔3 years
Grounding is required at termination points if _______ is present in the cable? ✔✔Metal Members
Unlike most communication cables what is not required with fiber optic cabling? ✔✔Labelling
What article in the NEC article states that unlisted cable shall extend no more than 50 feet inside the structure before transitioning to listed cables? ✔✔Article 770
Which article of the NEC requires that any electrically conductive materials that are likely to become energized, like metal armor and/or metal strength members of an optical fiber cable, shall be bonded and grounded at the point of entrance into a building or residence? ✔✔Article 250
What does NEC stand for? ✔✔National Electric Code
If the bend radius of a cable is not know, what is the generally accepted dynamic bend radius? ✔✔20x outside diameter
What class of Laster has the lowest power and the fewest hazards associated with it? ✔✔Class 1
How do you properly dispose of waste fiber ends? ✔✔Seal-able and marked container
What is important to take into consideration when installing new fiber runs? ✔✔Building Codes
Which termination kit has a single connector on one end and loose fiber on the other; and is designed to patch a long single mode fiber run? ✔✔Pigtail
What can be used to greatly reduce Fresnel Reflection that maintains nearly the same refractive index of the optical fibers? ✔✔Index Matching Gel
Which technique is dependent on the quality of the cleaving tool for optimum termination performance? ✔✔No Polish
What considerations should be accounted for regarding cable length when installing fiber optic cable? ✔✔Can't extend more than 50 ft into a building
True or False, Specifying fiber type is always required when using cable management products ✔✔False
When testing multimode Local Area Networks (LANs) wht two types of electro-optical light sources can be used in Visual Falut Locators? ✔✔LED and VCSEL
Are minor defects allowed anywhere on the end face of a connector? If so, where would those minor defects be allowed? ✔✔Yes, Outer Cladding
If you are looking at a cross section of a fiber optic cable which ring is identified as the core? ✔✔Middle, center,
What is the acronym for LASER? ✔✔Light Amplification Stimulated Emissions Radiation
What does the C and R stand for in OFCR ✔✔Conductive Riser
There are the 3 methods of fiber fabrication when making a reform, name two ✔✔Modified chemical vapor deposition (MCVD)
Outside Vapor Deposition (OVD)
What is the diameter for the Acrylate Coating on a European standard core? ✔✔50 um
What component of a light source is capable of converting light in to a electrical energy? ✔✔Photodiode
What is the term for the layer of the fiber strand that is used to restrict light to propagate and ensure Total Internal Reflection? ✔✔Cladding
Name three of the six advantages fiber optics cables have over copper cables ✔✔Wide bandwidth, low loss, electro-magnetic immunity
What does ETA stand for? ✔✔Electronic Technicians Association
Name 3 ways fiber optics is used today? ✔✔Medical, military, tele communications
True or false, you should never look directly into the end of fiber cables - especially with a microscope, until you are certain there is no light being transmitted down it? ✔✔True
What is the maximum manufacturer allowed arc count for the electrodes in a fusion splicer before it is recommended that the electrodes be replace before they become rounded and corroded? ✔✔ 1000
What is the diameter of a SC connector ferrule? ✔✔2.5 mm
The maximum insertion loss for a mated connector pair, as stated in the Optical Fiber Cabling Components Standard (ANSI/TIA-568-C.3) for commercial buildings, is how much? ✔✔.75 dB
___________ is reduced significantly by using Physical Contact (PC) or Angled Physical Contact (APC) ferrule finishes. ✔✔Reflectance
Periodic and traceable calibrations are required by which piece of test equipment? ✔✔OPM - Optical Power Meter
What tool is used to cut optical fibers in such a way that ends are cut to within 2 degree's perpendicular? ✔✔Precision Cleaver
True or false, it is not important to keep splicing environment as clean as possible ✔✔False
The TIA/EIA GR-326 CORE specification states that fiber optic connectors have a repeatability value (10 repeated connections or cycles) of not greater _______? ✔✔.2 dB
What is used to provide a central location for cross connecting, monitoring or testing a fiber connection? ✔✔Patch Pannel
What item is used, primarily by outside plant personnel, for the splicing and routing of optical cables? ✔✔Splice Closure
True or false, a microscope can confirm fiber continuity over short distances? ✔✔False
Name the test intrsutment used for the testing of fiber optic cables spans, and includes loss per kilometer and total distance of span measurements? ✔✔OTDR
What general factor must fiber optic installers must consider when installing fiber optic cables? ✔✔Building Codes
