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Connectors are key components in the performance of any voice, data and video (VDV) cable plant, either fiber or copper. While it is always important to install connectors skillfully, it is crucial to first choose the proper connector. Can you pick the right connector for the job? Answers and explanations are in red.
1. The copper connector, called an RJ-45, is really a __________.
A. Modular 8-pin connector with USOC pinout
B. Modular 8-pin connector with TIA-568A pinout
C. Modular 8-pin connector with TIA-568B pinout
D. Modular 8-pin connector with TIA-568C pinout
The copper connector called a RJ-45 is really a modular 8-pin connector with USOC pinout used on plain old telephone service (POTS) cables.
2. The difference between the TIA-568A and TIA-568B termination is __________.
A. Reversal of pairs two and three in a four-pair UTP cable
B. Whether Category 3 or Cat 5/6 cable is being terminated
C. Which update of TIA-568 standard is being used
D. What size wire is used in the UTP cable pairs
The difference between the TIA-568A and TIA-568B termination is the reversal of pairs 2 and 3 in a 4-pair UTP cable, allowed due to disagreements between participants who developed the original TIA-568 cabling standard.
3. Modular 8-pin connectors for Cat 3 and Cat 5/6 ___________.
A. Are the same
B. Differ in the number of pins connected
C. Have different pinouts to accommodate internal twists in the Cat 5/6 connector
D. Are terminated using different punchdown tools
Modular 8 pin connectors Cat 5/6 have internal twists to maintain the performance of the cables while Cat 3 connectors do not need this.
4. STP or ScTP copper cables use exactly the same connector as UTP.
STP or ScTP copper cables require special connectors and jacks to properly terminate the shielding on the cables.
5. Most fiber optic networks are terminated in __________ connectors, while equipment for gigabit (and faster) networks use __________ connectors.
A. ST, LC
B. SC, SC
C. ST or SC, LC
D. ST or SC, SC
Most cable plants still use ST or SC connectors while high speed communications equipment generally uses LC connectors. Hybrid jumper cables are needed to connect the equipment to the cable plant.
6. Practically all fiber optic connectors today are physical-contact connectors that should be polished on a __________ surface.
A. Hard flat
B. Flat glass
C. Hard rubber
D. Resilient rubber
Physical contact connectors have convex (domed) ferrules that should be polished on a resilient rubber pad placed on a flat surface.
7. The fiber optic connectors used for multimode and single-mode fibers are the same.
Singlemode connectors have holes in the ferrule that are smaller and more precisely made because of the tighter tolerances needed for the smaller core of singlemode fibers.
8. Prepolished/splice fiber optic connectors must be ordered to __________.
A. Match the fiber in the cables being terminated
B. Fit the termination kit used by the installer
C. Match the style (e.g., ST, SC, LC) of the connectors in the system
D. All of the above
The prepolished/splice connector must be of the right style of connector, have the internal fiber stub the same as the fiber being terminated and be compatible to the installer’s tool kit since each manufacturer has unique tooling.
9. Prepolished/splice fiber optic connectors work best when the fiber is __________.
B. Cleaved with a high-quality cleaver
C. Cleaned with isopropyl rubbing alcohol
D. Carefully polished before insertion in the connector
The secret to making a good prepolished/splice connector termination is a good cleave.
10. The best performance type of coax cable connectors are __________.
Compression coax connectors have the least loss and signal leakage.
HAYES is a VDV writer and educator and the president of The Fiber Optic Association. Find him at www.JimHayes.com.