New Mexico (NM) ES-7J Journeyman Telephone
Communication & Telephone Interconnect Systems
Practice Exam 200 Questions And Answers | 2025
Updated Solutions | 100% Correct Answers
1. What is the standard voltage range for a ringing signal in a traditional
telephone system?
o A) 12-24V AC
o B) 48-52V DC
o C) 90-105V AC
o D) 200-240V AC
Answer: C) 90-105V AC
Explanation: The ringing signal in POTS (Plain Old Telephone Service)
typically operates at 90-105V AC at 20 Hz to activate the ringer in a
telephone set.
2. Which wire pair in a standard RJ11 connector carries the primary telephone
signal?
o A) Red & Green
o B) Black & Yellow
o C) Blue & White
o D) Orange & Brown
Answer: A) Red & Green
Explanation: In an RJ11 connector, the inner pair (pins 3 & 4) is typically
red (ring) and green (tip), which carry the analog telephone signal.
3. What does POTS stand for in telecommunications?
o A) Private Office Telephone Service
o B) Plain Old Telephone Service
o C) Public Optical Telephone System
, o D) Primary Operator Telephone Switch
Answer: B) Plain Old Telephone Service
Explanation: POTS (or POTS) refers to the traditional analog telephone
service that uses copper wire networks.
4. Which protocol is commonly used in VoIP (Voice over IP) systems?
o A) HTTP
o B) SIP
o C) FTP
o D) TCP
Answer: B) SIP (Session Initiation Protocol)
Explanation: SIP is a signaling protocol used to establish, modify, and
terminate VoIP calls.
5. What is the purpose of a PBX (Private Branch Exchange) system?
o A) To connect multiple telephone lines within a business
o B) To provide internet service
o C) To regulate voltage in telephone lines
o D) To encrypt voice communications
Answer: A) To connect multiple telephone lines within a business
Explanation: A PBX allows internal phone extensions to communicate and
connects them to external phone networks.
6. Which type of signaling is used between telephone switches in digital
networks?
o A) DTMF
o B) SS7
o C) Analog loop start
, o D) Pulse dialing
Answer: B) SS7 (Signaling System No. 7)
Explanation: SS7 is a protocol suite used for setting up and tearing down
telephone calls in digital networks.
7. According to NEC, what is the minimum separation required between
communication cables and electrical wiring in a building?
o A) 2 inches
o B) 6 inches
o C) 12 inches
o D) 24 inches
Answer: A) 2 inches
Explanation: NEC Article 800 mandates at least 2 inches of separation to
prevent interference and safety hazards.
8. What is the primary purpose of a lightning arrestor in a telephone system?
o A) To boost signal strength
o B) To protect equipment from voltage surges
o C) To filter noise
o D) To convert analog to digital signals
Answer: B) To protect equipment from voltage surges
Explanation: Lightning arrestors divert high-voltage surges (e.g., from
lightning strikes) to ground, preventing damage.
9. If a telephone line has excessive static, what is the most likely cause?
o A) Faulty RJ45 connector
o B) Damaged cable insulation
, o C) Incorrect IP configuration
o D) Low battery in handset
Answer: B) Damaged cable insulation
Explanation: Static noise is often caused by moisture or physical damage
to the cable insulation, leading to crosstalk or interference.
10. What tool is used to test continuity and wiring faults in telephone cables?
• A) Multimeter
• B) Toner probe
• C) OTDR
• D) Spectrum analyzer
Answer: A) Multimeter
Explanation: A multimeter can check for continuity, shorts, or opens in
telephone wiring.
11. What is the function of a DSL filter in a telephone system?
• A) To block all incoming calls
• B) To separate voice and data signals
• C) To amplify the telephone signal
• D) To encrypt voice communications
Answer: B) To separate voice and data signals
Explanation: A DSL filter (or splitter) prevents interference between analog voice
signals and high-frequency DSL data signals on the same line.
12. Which of the following is a characteristic of analog telephone signals?
• A) Uses packet switching
• B) Continuous electrical waveforms
• C) Only transmits digital data
• D) Requires fiber-optic cables
Answer: B) Continuous electrical waveforms
Explanation: Analog signals are continuous waveforms, unlike digital signals,
which are discrete binary (0s and 1s).
Communication & Telephone Interconnect Systems
Practice Exam 200 Questions And Answers | 2025
Updated Solutions | 100% Correct Answers
1. What is the standard voltage range for a ringing signal in a traditional
telephone system?
o A) 12-24V AC
o B) 48-52V DC
o C) 90-105V AC
o D) 200-240V AC
Answer: C) 90-105V AC
Explanation: The ringing signal in POTS (Plain Old Telephone Service)
typically operates at 90-105V AC at 20 Hz to activate the ringer in a
telephone set.
2. Which wire pair in a standard RJ11 connector carries the primary telephone
signal?
o A) Red & Green
o B) Black & Yellow
o C) Blue & White
o D) Orange & Brown
Answer: A) Red & Green
Explanation: In an RJ11 connector, the inner pair (pins 3 & 4) is typically
red (ring) and green (tip), which carry the analog telephone signal.
3. What does POTS stand for in telecommunications?
o A) Private Office Telephone Service
o B) Plain Old Telephone Service
o C) Public Optical Telephone System
, o D) Primary Operator Telephone Switch
Answer: B) Plain Old Telephone Service
Explanation: POTS (or POTS) refers to the traditional analog telephone
service that uses copper wire networks.
4. Which protocol is commonly used in VoIP (Voice over IP) systems?
o A) HTTP
o B) SIP
o C) FTP
o D) TCP
Answer: B) SIP (Session Initiation Protocol)
Explanation: SIP is a signaling protocol used to establish, modify, and
terminate VoIP calls.
5. What is the purpose of a PBX (Private Branch Exchange) system?
o A) To connect multiple telephone lines within a business
o B) To provide internet service
o C) To regulate voltage in telephone lines
o D) To encrypt voice communications
Answer: A) To connect multiple telephone lines within a business
Explanation: A PBX allows internal phone extensions to communicate and
connects them to external phone networks.
6. Which type of signaling is used between telephone switches in digital
networks?
o A) DTMF
o B) SS7
o C) Analog loop start
, o D) Pulse dialing
Answer: B) SS7 (Signaling System No. 7)
Explanation: SS7 is a protocol suite used for setting up and tearing down
telephone calls in digital networks.
7. According to NEC, what is the minimum separation required between
communication cables and electrical wiring in a building?
o A) 2 inches
o B) 6 inches
o C) 12 inches
o D) 24 inches
Answer: A) 2 inches
Explanation: NEC Article 800 mandates at least 2 inches of separation to
prevent interference and safety hazards.
8. What is the primary purpose of a lightning arrestor in a telephone system?
o A) To boost signal strength
o B) To protect equipment from voltage surges
o C) To filter noise
o D) To convert analog to digital signals
Answer: B) To protect equipment from voltage surges
Explanation: Lightning arrestors divert high-voltage surges (e.g., from
lightning strikes) to ground, preventing damage.
9. If a telephone line has excessive static, what is the most likely cause?
o A) Faulty RJ45 connector
o B) Damaged cable insulation
, o C) Incorrect IP configuration
o D) Low battery in handset
Answer: B) Damaged cable insulation
Explanation: Static noise is often caused by moisture or physical damage
to the cable insulation, leading to crosstalk or interference.
10. What tool is used to test continuity and wiring faults in telephone cables?
• A) Multimeter
• B) Toner probe
• C) OTDR
• D) Spectrum analyzer
Answer: A) Multimeter
Explanation: A multimeter can check for continuity, shorts, or opens in
telephone wiring.
11. What is the function of a DSL filter in a telephone system?
• A) To block all incoming calls
• B) To separate voice and data signals
• C) To amplify the telephone signal
• D) To encrypt voice communications
Answer: B) To separate voice and data signals
Explanation: A DSL filter (or splitter) prevents interference between analog voice
signals and high-frequency DSL data signals on the same line.
12. Which of the following is a characteristic of analog telephone signals?
• A) Uses packet switching
• B) Continuous electrical waveforms
• C) Only transmits digital data
• D) Requires fiber-optic cables
Answer: B) Continuous electrical waveforms
Explanation: Analog signals are continuous waveforms, unlike digital signals,
which are discrete binary (0s and 1s).
