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Question 1. Which PPE item is essential when cutting copper cable with a wire cutter? A) Ear plugs B) Safety glasses C) Steel-toe boots D) High‑visibility vest Answer: B Explanation: Safety glasses protect the eyes from flying metal fragments generated while cutting cable. Question 2. The primary purpose of a Lockout/Tagout (LOTO) procedure during cable termination is to: A) Prevent tool theft B) Ensure the power source is isolated and cannot be re‑energized accidentally C) Keep the work area clean D) Document the work performed Answer: B Explanation: LOTO isolates hazardous energy, protecting workers from electric shock. Question 3. When storing solvent‑based adhesives, they should be kept: A) In direct sunlight B) Near open flames C) In a cool, well‑ventilated area away from ignition sources D) In a refrigerator Answer: C Explanation: Solvent adhesives are flammable; proper storage reduces fire risk.
Question 4. The most appropriate fire extinguisher class for an electrical fire caused by a cable short circuit is: A) Class A B) Class B C) Class C D) Class D Answer: C Explanation: Class C extinguishers are rated for energized electrical equipment. Question 5. Which of the following is a visual indicator that a voltage tester is functioning correctly? A) It beeps continuously B) Its LED indicator lights up when the probe contacts a live source C) The tester heats up D) It emits a loud alarm when the battery is low Answer: B Explanation: A functional tester shows an LED or indicator when voltage is detected. Question 6. Grounding a cable tray primarily prevents: A) Cable theft B) Signal attenuation C) Electrical shock and equipment damage from stray currents D) Moisture ingress Answer: C Explanation: Proper grounding provides a low‑impedance path for fault currents.
Question 10. Which component of a twisted‑pair cable provides the primary protection against electromagnetic interference (EMI)? A) Jacket material B) Twisting of the pairs C) Color coding of conductors D) Outer sheath thickness Answer: B Explanation: Twisting cancels out EMI by causing opposing magnetic fields in each twist. Question 11. Category 6A cable can reliably support a bandwidth of up to: A) 100 MHz B) 250 MHz C) 500 MHz D) 1000 MHz Answer: D Explanation: Cat 6A is rated for 500 MHz; however, the latest standards support up to 1000 MHz for 10 GbE over 100 m. Question 12. The main advantage of shielded twisted‑pair (STP) over unshielded twisted‑pair (UTP) is: A) Lower cost B) Easier termination C) Better protection against external EMI D) Greater flexibility Answer: C Explanation: STP includes a metallic shield that reduces susceptibility to external interference.
Question 13. Which marking on a copper cable jacket indicates it is a solid‑core cable? A) “S” in the code B) “C” for stranded C) “U” for unshielded D) “F” for foil‑shielded Answer: A Explanation: “S” typically denotes solid conductors; “C” denotes stranded. Question 14. In fiber optics, the core of a single‑mode fiber typically has a diameter of: A) 9 μm B) 50 μm C) 62.5 μm D) 125 μm Answer: A Explanation: Single‑mode fibers have a ~9 μm core to allow only one propagation mode. Question 15. Multi‑mode fiber OM3 is optimized for which laser wavelength? A) 850 nm B) 1310 nm C) 1550 nm D) 1625 nm Answer: A Explanation: OM3 is a laser‑optimized multi‑mode fiber designed for 850 nm VCSEL sources. Question 16. The primary difference between a tight‑buffer and a loose‑tube fiber cable is: A) Tight‑buffer fibers are only for indoor use
C) Satellite TV and broadband internet distribution D) Telephone voice lines Answer: C Explanation: RG‑ 6 ’s low loss at high frequencies makes it ideal for satellite and broadband. Question 20. The minimum bend radius for a 23‑AWG Cat 6 cable is: A) 2 times the cable diameter B) 4 times the cable diameter C) 6 times the cable diameter D) 10 times the cable diameter Answer: C Explanation: Industry practice specifies a minimum bend radius of 6 × diameter to avoid performance degradation. Question 21. When pulling a cable through a conduit, exceeding the maximum pulling tension can cause: A) Increased signal bandwidth B) Damage to the cable’s conductors or fibers, leading to attenuation C) Improved shielding effectiveness D) Reduced installation time Answer: B Explanation: Excess tension can stretch or break conductors/fibers, increasing loss. Question 22. The T568A wiring scheme differs from T568B primarily in: A) The order of the orange and green pairs B) The type of connector used C) The requirement for shielded cable only
D) The length of the cable run Answer: A Explanation: T568A swaps the positions of the orange and green pairs compared to T568B. Question 23. When terminating a Cat 6A cable on a 110‑type punch‑down block, the recommended untwist length at each termination point is: A) 0 mm (no untwist) B) 2 mm (≈ 1/8 in) C) 5 mm (≈ 1/4 in) D) 10 mm (≈ 3/8 in) Answer: B Explanation: Minimal untwist (≈ 2 mm) reduces crosstalk while allowing proper insertion. Question 24. Which tool is used to strip the outer jacket of a solid‑core Cat 6 cable without damaging the twisted pairs? A) Wire cutter B) Cable stripping tool with adjustable depth gauge C) Scissors D) Pliers Answer: B Explanation: A purpose‑built stripping tool sets the depth to avoid nicking the conductors. Question 25. In an RJ‑45 modular plug, the “strain relief” component serves to: A) Increase signal speed B) Prevent the cable jacket from pulling out of the connector under tension C) Provide shielding for the conductors D) Reduce electromagnetic interference
D) White‑blue, blue, white‑brown, brown, white‑green, green, white‑orange, orange Answer: B Explanation: T568B follows the color sequence listed in option B. Question 29. In coaxial cable termination, the correct length of the exposed center conductor for an F‑type connector is: A) 1 mm B) 3 mm C) 5 mm D) 7 mm Answer: C Explanation: Approximately 5 mm of the center conductor should be exposed to ensure proper contact. Question 30. When preparing a coaxial cable for a BNC connector, the dielectric should be trimmed to leave a gap of about: A) 0.5 mm B) 1 mm C) 2 mm D) 3 mm Answer: B Explanation: A 1 mm dielectric gap allows the connector’s pin to seat correctly without crushing the dielectric. Question 31. The primary purpose of a fiber cleaver is to: A) Strip the outer jacket of the fiber cable B) Produce a clean, perpendicular end face with a precise angle
C) Polish the connector ferrule D) Apply epoxy to the fiber end Answer: B Explanation: A cleaver creates a smooth, flat end face essential for low‑loss splicing. Question 32. Which solvent is recommended for cleaning a bare fiber before splicing? A) Acetone B) Isopropyl alcohol (≥ 90 %) C) Mineral oil D) Water Answer: B Explanation: High‑purity isopropyl alcohol removes contaminants without leaving residues. Question 33. In fusion splicing, the “splice loss” is primarily caused by: A) Incorrect cleave angle B) Excessive heat in the splice heater C) Using a mechanical splice instead of fusion D) Over‑polishing the connector end‑face Answer: A Explanation: A poor cleave angle leads to misalignment and higher loss during fusion. Question 34. Mechanical splicing of multimode fiber is most appropriate when: A) Permanent, high‑performance connections are required B) A quick, temporary connection is needed for testing C) The fiber must be buried underground D) The installation is in a high‑temperature environment
Explanation: Detailed as‑built drawings capture all physical and logical aspects for future maintenance. Question 38. A certified cable analyzer reports a NEXT value of – 55 dB on a Cat 6 link. This result indicates: A) The link meets the minimum NEXT requirement for Cat 6 (‑ 50 dB) B) The link fails because NEXT is too low (more negative is better) C) The link is borderline; further testing is needed D) The test was performed incorrectly Answer: A Explanation: For Cat 6, the minimum NEXT requirement is – 50 dB; – 55 dB is better (more negative) and thus acceptable. Question 39. In an OTDR trace, a sudden increase in back‑scatter level followed by a rapid drop typically represents: A) A fiber break (complete loss) B) A splice loss event C) A connector reflection (Fresnel) D) A fiber bend loss Answer: C Explanation: A Fresnel reflection appears as a sharp peak (increase) due to a discontinuity, then drops. Question 40. The acceptable insertion loss for a 100 m run of OM3 multimode fiber at 850 nm is: A) ≤ 0.5 dB B) ≤ 1.0 dB C) ≤ 3.0 dB
D) ≤ 5.0 dB Answer: C Explanation: OM3 typically allows up to 3 dB loss over 100 m at 850 nm. Question 41. When performing a continuity test on a copper patch cable, a “open” reading indicates: A) All conductors are correctly connected B) One or more conductors are broken or not making contact C) Excessive crosstalk D) Incorrect wiring scheme Answer: B Explanation: An open circuit means the test path is incomplete. Question 42. The term “skew” in copper cable testing refers to: A) Difference in propagation delay between pairs, affecting high‑speed data integrity B) The amount of signal loss over distance C) The level of electromagnetic interference D) The resistance of the cable conductors Answer: A Explanation: Skew is the time difference between the fastest and slowest pairs, critical for 10 GbE. Question 43. A fiber optic patch panel should be mounted at a height that allows easy access while meeting which code requirement? A) Minimum 300 mm above the floor B) Maximum 2 m above the floor for safety and ergonomics C) Exactly 1.5 m for all installations
C) “Cable Type‑Color‑Length” D) Any format as long as it is legible Answer: A Explanation: A hierarchical format (building‑floor‑panel‑port) provides clear location information. Question 47. A high level of Near‑End Crosstalk (NEXT) on a Cat 6 cable most likely indicates: A) Excessive shielding B) Improper untwisting or too long untwist at termination C) Use of a solid‑core cable in a stranded application D) Incorrect fiber connector polish Answer: B Explanation: Excessive untwist increases coupling between pairs, raising NEXT. Question 48. Which of the following is the most accurate method for measuring the length of a fiber optic link? A) Using a ruler on the cable sheath Answer: B Explanation: OTDR provides precise length measurement and identifies loss events. Question 49. When performing a field splice on a single‑mode fiber using a mechanical splice, the required fiber preparation includes: A) Stripping only the outer jacket B) Removing the buffer tube, cleaning the bare fiber, and cleaving to a 2‑degree angle C) Leaving the buffer intact and using a splice sleeve D) Using a fusion splicer instead of mechanical splice
Answer: B Explanation: Mechanical splices need clean, properly cleaved bare fibers for alignment. Question 50. The primary benefit of using a “pre‑polished” fiber connector (e.g., SC‑APC) versus a field‑polished connector is: A) Lower cost B) Faster installation with consistent polish quality C) Ability to splice without a cleaver D) Compatibility with multimode fiber only Answer: B Explanation: Pre‑polished connectors are manufactured with a finished end‑face, reducing field polishing time and variability. Question 51. In a cable tray, the recommended separation between power and data cables to minimize EMI is: A) 5 mm B) 15 mm C) 30 mm D) 50 mm Answer: C Explanation: A 30 mm separation is commonly recommended to reduce electromagnetic coupling. Question 52. If a copper cable tester shows a “reverse polarity” error on a RJ‑ 45 connection, the most likely cause is: A) Using a T568A scheme on one end and T568B on the other B) Open circuit on one pair
D) Mount RJ‑45 keystone jacks Answer: B Explanation: Splice trays provide a structured environment for splices and terminations. Question 56. When testing a fiber link, the “loss budget” is calculated by: A) Adding the connector loss, splice loss, and fiber attenuation and comparing to the total allowable loss B) Measuring the temperature of the fiber C) Counting the number of fibers in the bundle D) Determining the cable’s outer jacket thickness Answer: A Explanation: The loss budget accounts for all expected losses to ensure the link stays within specifications. Question 57. Which of the following is a symptom of a “split pair” fault in a copper cable? A) High return loss only B) Increased NEXT and reduced bandwidth due to crosstalk between non‑adjacent pairs C) No continuity on any pair D) Low insertion loss but high attenuation Answer: B Explanation: Splitting pairs (mixing wires from different pairs) creates excessive crosstalk, degrading performance. Question 58. The most common cause of a “high insertion loss” reading on a newly terminated RJ‑45 patch cord is: A) Using a shielded connector on unshielded cable B) Excessive untwisting length at the termination point
C) Incorrect color coding of wires D) Using a solid‑core cable with a stranded connector Answer: B Explanation: Over‑untwisting introduces impedance mismatches and increases loss. Question 59. In a fire‑rated building, which cable rating is mandatory for any horizontal distribution in a riser shaft? A) CM (general‑purpose) B) CMR (riser) C) CMP (plenum) D) CMX (outdoor) Answer: B Explanation: Riser shafts require CMR‑rated cable to limit flame spread between floors. Question 60. When performing a field termination of a multimode fiber with an LC connector using the epoxy method, the curing time for the epoxy is typically: A) 30 seconds B) 2‑ 3 minutes C) 5‑ 10 minutes D) 30‑ 45 minutes Answer: C Explanation: Standard epoxy for fiber connectors requires several minutes to fully cure for optimal strength. Question 61. Which of the following best describes “attenuation” in a copper cable? A) The delay of the signal as it travels through the cable B) The reduction in signal amplitude caused by resistance, capacitance, and dielectric loss
