NCT 4 Test

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CLI

The mathematical value derived from the number and severity of leaks in a system

Mop up/Response EQ

This amplifier circuit is used to compensate for amplifier signatures?

UDP

This assumes a noiseless transmission path so it will not retransmit data that was not received. This protocol is used in real time applications like VOIP?

BER

What detects erorred bits in the system?

Analog signal

a continuous signal or carrier that varies in amplitude or frequency as a function of changes at its input

Baud

or symbol, refers to the number of changed states or "events" that can occur per Hertz (second)

Digital Signal

A discontinuous signal whose various states are discrete intervals apart

Signal Level Meter (SLM)

A frequency selective receiver capable of tuning in a desired frequency/channel with a display showing the RF signal strength (dBmV)?

Power passing chokes or capacitor leak in passive devices.

A primary source of hum modulation is?

Common Path Distortion (CPD)

A return path impairment that can have a severe effect on return path signal quality.

Protocols

A set of rules for how devices on a network will communicate?

Peak

Analog measurements are a________ power

quasi-square wave

CATV network powering is generally ?

26.9-27.1

CB Radio frequency

Channel bonding

Combining 4 or 8 6hz channels to form a wideband 24mhz or 48mhz channel?

Isolation

Cross talk between passive device ports can be minimized when the passive device has good?

Channel bonding, Ipv6

DOCIS 3.0 brought 2 noteable enhancements over prior versions?

Digitizer

Device used to convert an analog signal to a digital signal

Discrete Second Order Composite Second Order (CSO) Discrete Third Order Composite Third Order or Composite Triple Beat (CTB) Cross Modulation (XMOD)

Different types of distortions

Average

Digital measurements are a ________ power

RMS

Elevated AC voltage in the network. Using a true_ volt meter allows for an actual voltage measurement, rather than one that reads higher because it has been averaged.

Ghosting

For analog T.V, receiving a signal of the same content and same frequency just before or just after the desired signal will produce what visual result

ASK

Frequency and phase of the signal carrier is constant but the amplitude is varied

DMM

How can optical power be measured non intrusively?

Total internal reflection

How does light propagate through the fiber?

3b

If direct or reflected beam is viewed

Amplifier

Inter Modulation Distortion (CSO +CTB) is created in what device

Co- Channel interference

Is caused in one channel by the carrier from another transmitter operating on the same channel

Coaxial, Dielectric,shield distance

List 3 Physical things that determine a coaxial cables impedance

Resistance, Capacitance,inductance

List 3 electrical properities that cables impedance looks like to RF signal

Cross Modulation (XMOD)

Literally means the "crossing" of modulation from one channel to another.

mw, dbm

Optical power is measured in these units___ or ____-

A partial open

Refers to a cable that has not been completely cut

Bit

Refers to an electrical impulse representing a zero or one—the smallest unit of measurement a computer can handle

MPEG Compression

Removing Redundant static information to save bandwidth without losing digital quality

Voice of America, CB, and Amateur Radio transmitters

Return direction can suffer ingress from which transmitters operating in that frequency?

Hum Modulation

Superimposing 60hz AC onto RF signal

0,1

The RF signal level in CATV is reported in dBmV. The baseline,_____ dBmV, is equal to _____ millivolt

Quantization

The assigning of a specific value to each of the samples

Impedance mismatch

The condition that results when two components of a system are operating at different impedance ?

Structural Return loss, Return loss

The difference between the desired signal level and the reflected(return) signal level with the coaxial cable? At active and passive device connections?

C/N ratio

The difference between the peak carrier level, measured in dB, and the noise level, also measured in dBmV.

6 MHz

The difference in frequency between any two adjacent channels is

NF, Flat

The first stage amp.(sometimes called trunk) is selected to have a low _____ and it should have ____ levels across the bandwidth it input?

Amplitude Shift Keying (ASK) Frequency Shift Keying (FSK) Phase Shift Keying (PSK) Quadrature Phase Shift Keying (QPSK) Quadrature Amplitude Modulation (QAM

The five most common digital modulation schemes used today are:

FM

The means of superimposing sound on an RF carrier of a particular frequency,the frequency changes in relation to the voltage detected by the analog input.

AM

The means of superimposing sound on an RF carrier. The frequency stays constant but the amplitude of the carrier varies in proportion to the voltage detected by the analog input.

0 dBmV, with a maximum of 15 dBmV.

The minimum signal level at the input to the customer's television is?

Amplitude

The peak of an AC waveform is known as

Encoding

The process by which these specific values are converted into a data or bit stream

Impedence

The resistance a cable has to AC

Impedance

The resistance of a circuit (cable, passive devices are examples) to alternating current.?

Beat

The unwanted sum of and/or difference in frequencies resulting from the heterodyning (mixing) of two or more signals

−59.2

Thermal noise (The noise floor in a 4 MHz bandwidth at 68º F, in dBmV)

Boot file

This file controls and configures all aspects of the CM(US,DS, Bondin,Mac,etc)

Spectral Re-growth. Multipath and Reflections. Phase Noise.

Three digital distortions you should be concerned with are

Spectral re-growth

Typically an overload effect noted through digital signal processing equipment.

CMTS, Cable modem

What 2 components are required in a docsis compliant system?

3a

What Laser class is an eye hazard if the beam is collected or focused on the eye?

Root Mean Square Meter (RMS)

What accurately measures AC voltages of signals other than pure analog sine waves ?

video, color, and audio

What are the three carriers of Analog signal/

Water migration

What can cause a change in the characteristic impedance of the cable, resulting in reflections and signal distortions?

Reverse Sweep

What can uncover mismatch problems, revealed as standing waves, or diplex filter roll-offs that can severly degrade the quality of services carried in the reverse band

improve by 3db

What happen to c/n if the input are raised by 3db_______

108-137Mhz

What is Aeronautical frequency

Cycles per second, hertz

What is CPS? And is the same as ?

88-108Mhz

What is FM Radio frequency

700-800MHz

What is LTE frequency

Ingress

What is a Passage of an outside signals into the cable; can result in noise and disruption of the desired signal?

A short

What is a situation where the center conductor comes in contact with the shield ?

MER

What is an indicator of transmission quality degradation resulting from noise, ingress, and composite distortions, What is an overall quality measurement that can be performed on a digital QAM carrier?

Sampling Quantization Encoding

What is the 3 step process of converting an analog signal into a digital signal (ADC)

108-137Mhz

What is the aeronautical frequency range

700-800Mhz

What is the frequency range of LTE

8-9 microns,125microns,250microns

What is the size of the Core, Cladding and Coating in (SM) fiber?

(SLM) Signal Level Meter

What is used to measure signal level (in dBmV) at specific tunable frequencies?

100%

What percent of signal is reflected through open ports or shorts

A sweep trace

What reveals every physical error in the network that influences transmitted signals?

59.2db

Whats the output c/n when the input level = NF________

Cable Locator

Whats used to find the location or path of underground cables?

Compare out to in

When Sweeping how can you identify if a response problems is before it or only at its output

Unit gain

When sweeping if the amps have the same response and tilt as the node, then _____ ______ has been achieved?

Waveform TDR

Which is more accurate than digital TDRs or waveform TDR and can detect smaller faults and multiple faults?

SCDMA

With this the CMTS allows multiple CMs to transmit on the same carrier at the same time?

Digital Transmission

a non-continuous signal or carrier that changes its output in discreetly timed steps of voltage level and/or phase that can represent numerical values or other information

Byte

is a group of eight bits used to represent a letter or numeral, or a measurement unit representing storage capacity.

Db or bel

is the unit for expressing, in logarithmic terms, the ratio between two power levels.

T4 timeouts

A CM did not receive a maintenance opportunity from the CMTS within the 30-35 second time window?

T3 timeouts

A CM sent 16 RNG Req and did not receive any Rng -RSp from the CMTS?

Oxidation

A chemical change caused by a reaction to oxygen, such as rust.

Harmonics

A component frequency of the signal that is an integer multiple of the fundamental frequency.

54-216mhz

Across what frequency range does the fcc require signal leakage to be less than 20mv/m@3 meters

Docsis

An international Telecom standard for high speed data transfer on a CATV system?

No

Does fiber have impedance?

FEC

In Docsis additional bits are added to the codeword these additional bits are for what purpose?

No

Is Common Path Distortion, ingress related?

Ghost

Is caused when an analog TV signal (of the same frequency and video content) arrives at a receiver just before, or just after, the desired TV signal

Length, Diameter

List 2 things that determine a cables DC loop Resistance

Sampling

The "measuring" of the analog signal at specific intervals

TDMA

The CMTS allocating specific times for CMs to transmit data?


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