Chapter 6 - ICT Cables and Connecting Hardware Flashcards
On singlemode optical fiber, a convex physical contact (PC) connector delivers return loss performance in the range of:
a. 20 dB to 30 dB
b. 50 dB to 60 dB
c. 40 dB to 50 dB
d. 30 dB to 40 dB
c. 40 dB to 50 dB
p 6-93
Singlemode optical fiber jumpers typically feature a convex PC polish on the end of the fiber terminated connector ferrule surface to ensure proper fiber contact. This connector design reduces the Fresnel reflection and delivers return loss performance in the range of 40 dB to 50 dB.
On singlemode optical fiber, an APC connector features a slight angle (8 degrees) to further reduce reflectance, resulting in better return loss than PC connectors (60 dB).
Overall bandwidth of optical fiber is a derivative of two components: modal dispersion and chromatic dispersion. In multimode optical fiber, _____ predominates.
a. Modal dispersion
b. Chromatic dispersion
a. Modal dispersion
p 6-18
In multimode, modal dispersion predominates, and chromatic dispersion is negligible; in singlemode, it is the opposite.
Optical fiber cabling applications are length restricted on the style of cabling. For 1 Gb transmission standards, what is the typical distance supported by OM1 cable?
a. 220 m (722 ft)
b. 300 m (984 ft)
c. 550 m (1800 ft)
d. 1000 m (3281 ft)
a. 220 m (722 ft)
p 6-18 see Table 6.6
Screened balanced twisted-pair cable assemblies stranded conductor is typically:
a. 22 AWG
b. 24 AWG
c. 26 AWG
c. 26 AWG
p 6-71
A screened cable assembly’s stranded conductor is typically 26 AWG. Because of additional capacitive electromagnetic coupling between the cable conductors and screen, screened cable assemblies can exhibit increased insertion loss compared with equivalently-sized solid conductors.
____ connecting hardware is a one-piece pass-through unit that is reversed in its mount after the cable termination to expose the opposite side and provide a cross-connect field.
a. 66-style
b. 110- style
c. BIX-style
d. LSA-style
c. BIX-style
p 6-67
Unlike 110-style connecting hardware, which places clips on top of the wiring block, BIX-style equipment is a one-piece pass-through unit that is reversed in its mount after the cable termination to expose the opposite side and provide a cross-connect field (see Figure 6.30)
A number of measurable characteristics control the transmission performance of a balanced twisted-pair cable. Which one of the following is not considered to be a primary parameter?
a. Capacitance
b. Conductance
c. Resistance
d. Return loss
d. Return loss
p 6-10
Primary parameters, which depend on the physical nature of the conductor—materials (conductivity and permittivity) and dimensions (wire gauge [copper diameter], insulation diameter and thickness, conductor spacing)—are: –Resistance (R). –Conductance (G). –Inductance (L). –Capacitance (C)
For screened (shielded) balanced twisted-pair cable the screening material type, thickness and relative coverage determines the effectiveness of the screen. ___ effectively blocks lower frequency (below 30 MHz) electromagnetic fields.
a. Foil
b. Copper braid
b. Copper braid
p 6-11
The screen’s characteristics are such that the:
• Foil typically blocks higher frequency (30 MHz and higher) electromagnetic fields.
• Copper braid effectively blocks lower frequency (below 30 MHz) electromagnetic fields.
The overfilled launch (OFL) bandwidth for OM3 multimode optical fiber cable at a wavelength of 850 nm is:
a. 1500 MHz-km
b. 2000 MHz-km
c. 3500 MHz-km
d. 4700 MHz-km
a. 1500 MHz-km
p 6-15 see Table 6.5 - Optical fiber cable transmission performance parameters.
Note, all multimode at wavelength of 1300 nm = 500 MHz-km
Study all parameters in the table and understand the difference between overfilled launch (OFL) and effective modal bandwidth (EMB). They’re on the test.
Series-11U coaxial cable has a ___ center conductor.
a. Stranded
b. Solid
a. Stranded
p 6-25
Series-11U has a(n):
• Characteristic impedance of 75 ohms.
• Coated foil shield over the dielectric to shield against high frequencies.
• Braided shield over the coated foil to shield against low frequencies.
• 18 AWG stranded center conductor.
• F- or N-style connector.
Which one of the following is not an advantage associated with 110-style connectors?
a. Short termination time
b. Can be used in a number of different styles of connecting hardware
c. Allows connections to be created in one-pair increments
d. Stand-alone connectors also available in a screened version
d. Stand-alone connectors also available in a screened version
p 6-35
The 110-style connector’s disadvantage is that it does not exist in screened versions as a stand-alone connector.
Fusion optical fiber splices shall have a minimum return loss of _____ for multimode fiber.
a. 30 dB
b. 26 dB
c. 20 dB
d. 12 dB
c. 20 dB
p 6-87
Fusion and mechanical optical fiber splices shall have a minimum return loss of 20 dB for multimode and 35 dB for singlemode
The most common tight-buffer diameter is:
a. 900 μm
b. 600 μm
c. 250 μm
d. 125 μm
a. 900 μm
p 6-21
The most common tight-buffer diameter is 900 μm, although other diameters are available.
Has the most common loose-tube optical fiber diameter of 250 μm, although other diameters are available.
SC-style optical fiber connector’s disadvantage is that it does not feature an SFF design.
a. True
b. False
a. True
p 6-82
___ indicates the conductors insulation’s ability to transmit an electric field.
a. Conductivity
b. Permittivity
b. Permittivity
p 6-9
Permittivity indicates the insulation’s ability to transmit (or permit) an electric field.
A majority of the modular connectors used in telecommunications are categorized as performance level 1 (PL1). Such connectors are rated for _____ mating cycles.
a. 2500
b. 1400
c. 750
d. 200
c. 750
p 6-44
PL 1 is rated for 750 mating cycles and PL 2 connectors (rated for 2500 mating cycles) are also available.
