MAINTENANCE TECH I-II CONVENTIONAL UPDATED ACTUAL QUESTIONS AND CORRECT ANSWERS

MAINTENANCE TECH I-II CONVENTIONAL UPDATED
ACTUAL QUESTIONS AND CORRECT ANSWERS

Question:
1. What advantage is realized by increasing the voltage in a broadband cable network from 60 volts
alternating current (VAC) to 90 volts?
Answer:
Operating with 50% more voltage reduces the voltage drop and current drawn in the network for more
efficient power utilization.

Question:
2. How does surge protection at the input and output of a ferroresonant power supply defend against
voltage surges?
Answer:
By passing voltage surges (within the surge device rating) to ground without damage.

Question:
3. Which part of a ferroresonant transformer regulates the load on the secondary winding?
Answer:
The magnetic shunt.

Question:
4. In a standby network power supply, what comes online to convert the battery voltage to alternating
current (AC), which then goes to the ferroresonant transformer?
Answer:
The battery-powered inverter.

Question:
5. In a power inserter with three filtering networks, what is the purpose of the high-pass filter?
Answer:
To prevent the 60 hertz (Hz) alternating current (AC) from passing between the two radio frequency
(RF)/AC ports.

Question:
6. What inserts alternating current (AC) into the network with a direct connection to an amplifier rather
than using a power inserter?
Answer:
The amplifier AC circuitry.

Question:
7. What is the advantage for supplying alternating current (AC) to multiple amplifiers from one network
power supply?
Answer:
Allows the designer to place amplifiers without concern about access to electrical utility power.

, Question:
8. Where is a clamp-on ammeter attached to measure the output current from a network power supply?
Answer:
Clamped around the conductor attached to the lug that tightens down on the coaxial cable connector pin.

Question:
9. What is a priority in any standby power supply maintenance program?
Answer:
Battery care.

Question:
10. What is the voltage into the second amplifier in cascade, if each amplifier draws 1.5 amps of current,
the loop resistance of each section of cable is 1.38 ohms, and the alternating current (AC) source is a 90
volts AC (VAC) network power supply?
Answer:
83.77 VAC.

Question:
11. What enables set-top boxes (STB) and Data Over Cable Service Interface Specification (DOCSIS)
modems to operate as completely separate systems that operate independent of each other?
Answer:
STB and DOCSIS modems are assigned different upstream channels with dedicated receivers in the
headend.

Question:
12. What did the 1.1 version of the Data Over Cable Service Interface Specification (DOCSIS) introduce,
incorporating solutions for transporting real-time data applications (such as voice traffic) over the cable
operator's managed IP network, and doing so with quality comparable to that of the telephone company?
Answer:
PacketCable.

Question:
13. Why is 38 MHz typically the highest frequency in the sub-band frequency that is used for upstream
modem transmissions?
Answer:
The upper edge of the sub-band frequency spectrum is prone to group delay caused by the diplex filters.

Question:
14. What enables the set-top box (STB) upstream carrier to be located below 20 MHz and still be reliably
received?
Answer:
The narrow bandwidth and quadrature phase shift keying (QPSK) modulation.

Question:
15. What system is a byproduct of the "funneling effect"?
Answer:
A many-to-one system.