What are three principle characteristics that define an AC waveform? - Answer- The three principle characteristics that define an AC waveform are: (1) frequency; (2) wavelength; and (3) amplitude.
What is one of the basic principles of resistance reflected in the familiar practices of grounding ...
what are three principle characteristics that defi
what is one of the basic principles of resistance
what comprises the impedance of a coaxial cable or
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What are three principle characteristics that define an AC waveform? - Answer- The
three principle characteristics that define an AC waveform are: (1) frequency; (2)
wavelength; and (3) amplitude.
What is one of the basic principles of resistance reflected in the familiar practices of
grounding and bonding? - Answer- Grounding and bonding practices reflect the basic
principle that electricity always follows the path of least resistance.
What comprises the impedance of a coaxial cable or a device (connector, passive,
etc.)? - Answer- The impedance comprises the combined effects of a coaxial cable's or
a device's resistance, inductance, and capacitance.
What is a high pass filter? - Answer- A high-pass filter is a type of bandpass filter that
passes all frequencies above a specific frequency (e.g., 50 MHz), and eliminates
common path distortions, impulse noise in the return spectrum, and any other
frequencies that fall below that specific frequency.
What are the differing forward-path transmission bandwidths for traditional tree-and-
branch and HFC architectures? - Answer- The feeder system in a traditional tree-and-
branch architecture supplies the forward signal up to a 50-550 MHz pass band, and the
distribution system in an HFC network transmits the forward signal up to a 50-1,000
MHz pass band.
Where does the feeder system forward path start and end in a tree-and-branch design?
- Answer- A tree-and-branch feeder system forward path starts at the output of the
bridger amplifier module in the trunk/bridger amplifier station and ends at the tap port of
an RF tap.
Where does the distribution system forward path begin and end in an HFC design? -
Answer- An HFC distribution system forward path begins at the output of an RF
amplifier located in the optical node and ends at the tap port of an RF tap.
What is the purpose of a coaxial express cable in an HFC distribution system? -
Answer- A coaxial express cable allows a particular optical node to reach farther out in
the distribution system.
How is underground cable manufactured? - Answer- Underground cable is
manufactured with a protective outer jacket covering the aluminum sheath and flooding
compound between the jacket and the sheath.
,How do frequency and cable size affect the attenuation of a broadband signal? -
Answer- The attenuation of a broadband signal increases with higher frequencies and
decreases with larger cable size.
What is the role of splitters and directional couplers in the forward and return paths? -
Answer- Splitters and directional couplers divide and route the forward RF signal
transmission throughout the distribution system, and combine return-path signals
arriving from separate feeder runs.
How is AC power transmitted in an RF tap? - Answer- AC power passes bidirectionally
through the tap, but is prevented from passing through to the tap ports except by design
in power-distributing taps.
What is the distinction between a line extender amplifier and a distribution amplifier? -
Answer- The distinction is a line extender, which has a single output port and a
distribution amplifier, or minibridger, which has multiple output ports (typically three
ports; a through-port and two auxiliary output ports).
What are five important components of an amplifier station? - Answer- Five important
amplifier station components are: (1) input and output diplex filters that separate and
combine the forward and return paths within the amplifier; (2) forward and return plug-in
pads and equalizers for controlling the input signal levels; (3) an RF amplifier module;
(4) an integrated or stand-alone DC power supply with DC current fusing; and (5) AC
power direction control.
What factors define the extent of a power realm? - Answer- Cable resistance, combined
amplifier load requirements, individual amplifier voltage minimums, and limits on AC
current define the extent of power realms.
What are the three main components of a typical standby power supply? - Answer- The
three main components of a standby power supply are: (1) a ferroresonant transformer
that supplies the output voltage; (2) a set of batteries acting as a backup power source;
and (3) an AC inverter that converts the DC battery backup power to a 60 or 90 VAC
output.
What does a signal level meter (SLM) measure? - Answer- An SLM measures individual
analog video and audio, and digital carrier levels.
What does a digital multimeter (DMM) measure? - Answer- A digital multimeter (or
VOM) measures AC and DC voltages, resistance for continuity checks, and current.
What does a time domain reflectometer (TDR) measure? - Answer- A TDR measures
the presence of and distance to cable faults.
,What does a signal leakage detector measure? - Answer- A signal leakage detector is
an RF receiver with an installed input antenna that measures broadband cable signals
leaking from the system within FCC assigned aeronautical frequency bands.
What does a combination SLM/leakage detector measure? - Answer- A combination
SLM/leakage detector incorporates the features of both an SLM and a signal leakage
detector.
What are measurement applications for using SLMs, DMMs, TDRs, leakage detectors,
and combination leakage detectors? - Answer- The measurement applications include:
(1) balancing amplifier (bridger, distribution, and line extender) output levels (SLM); (2)
verifying system and amplifier power supply operation (DMM); (3) identifying cut or
damaged cable spans (TDR); (4) identifying sources of ingress (signal leakage detector,
SLM); and (5) monitoring and measuring signal leakage (egress) for system CLI
reporting (combination SLM/leakage detector).
What is the proper troubleshooting technique? - Answer- Begin at a location common to
all known outage sites, divide the area of unknown signal status in half, verify the signal
condition, and repeat (if necessary) until the source of the problem is found.
How can a distribution system design map aid the troubleshooting process, after
gathering as much information as possible about the extent of the affected area? -
Answer- A system design map is used to analyze system for the device common to the
customers so far affected before traveling to make additional signal status checks.
What are six sources of outages caused by powering failures? - Answer- Powering
failures include: (1) a utility power failure; (2) a tripped utility breaker; (3) spent standby
battery power; (4) a blown distribution leg fuse; (5) a blown amplifier DC power supply
fuse; and (6) a cable center conductor suck-out.
What are three groups of outage causes associated with cut or damaged cables? -
Answer- The outage groups are: (1) cables cut by underground digging equipment (a
backhoe, a trencher, a post-hole digger, a shovel, etc); (2) aerial cable damaged by
lightning or downed power lines; and (3) downed aerial cable due to traffic accidents or
severe weather.
How often are outages caused by equipment failures? - Answer- Outages caused by
equipment failures generally occur less frequently than other outage categories.
What tasks are involved in maintaining physical plant integrity within the distribution
system? - Answer- Maintaining physical plant integrity involves: (1) checking and
tightening loose connectors, housing enclosures, and tap face plates; (2) lubricating
pedestal and power supply padlocks periodically during normal access; and (3) securing
and documenting any broken lashing wire to prevent further deterioration.
, What does eliminating a discovered signal leak accomplish? - Answer- Eliminating a
discovered leak averts a potential outage or trouble call.
What are six performance checks involved in maintaining power supplies? - Answer-
Power supply performance checks include: (1) AC input voltage; (2) AC output voltage;
(3) output current (amperage) draw; (4) individual battery voltages; (5) charging (float)
voltages; and (6) standby switching capability.
When does alternating current change direction in the conductor? - Answer- Alternating
current changes direction (or alternates) in the conductor each time the potential
difference applied to the ends of the conductor changes (or alternates) its polarity.
Define an AC power source. - Answer- An AC power source is a potential difference in a
circuit that continually changes its polarity.
What term is used more commonly than "alternator" to describe an AC power source? -
Answer- AC generator" is the term used more commonly than "alternator" to describe
an AC power source.
What does an AC generator produce using magnetism and mechanical motion? -
Answer- An AC generator produces AC voltage using magnetism and mechanical
motion.
Define "flux lines." - Answer- "Flux lines" are magnetic lines of force running
longitudinally from the north pole to the south pole of a magnet.
What is the left-hand rule? - Answer- The left-hand rule states that when the index
finger points in the direction of the magnetic field and the thumb points in the direction
that the conductor moves through a magnetic field, the middle finger points in the
direction that the electromotive force causes the current to flow.
Where does the AC voltage appear in an AC generator consisting of a loop of wire
rotated between the poles of a magnet? - Answer- The AC voltage appears across the
gap between the ends of the loop in an AC generator consisting of a loop of wire rotated
between the poles of a magnet.
What is a slip ring in an AC generator consisting of a loop of wire rotated between the
poles of a magnet? - Answer- A slip ring is a smooth circular band of conducting
material connected to one end of the loop, in an AC generator consisting of a loop of
wire rotated between the poles of a magnet.
List three mechanical forces used to turn the armature of AC generators in large-scale
AC power production. - Answer- Flowing water, burning coal to produce steam, and
using a nuclear reactor to produce steam are three mechanical forces used to turn the
armature of AC generators in large-scale AC power production.
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