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Flashcards in cct4 Deck (237)
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121

What wireless adapter is credit-card sized wireless adapter that slides into the side of a laptop or desktop?

PC (PCMCIA) Card

122

What troubleshooting utility can you use in order to determine the computer's IP address, and to reset the address if the computer cannot connect to the Internet?

IPConfig

123

Which Business Class Internet optional feature allows customers to operate VPN or Web and E-Mail servers without the fear of interruption?

Static IP Addresses

124

How does a technician initiate a telnet session?

In the command prompt, type in Telnettype open and the (cm ip address)Enter username: msoEnter password: (password of the day)

125

What command in telnet will allow a technician to packet sniff both upstream and downstream for 3 seconds in Comcast's format?

sniff u+d 3 1

126

What does a technician type to display the existing NAT session log in a telnet session?

natShow

127

In a telnet session, what does a technician type to show the current dhcp lease info, including the IP, MAC and status of the private LAN?

dhcpShow

128

What calling feature allows different phone numbers to reach the same phone line with different ring patterns?

Distinctive Ring

129

A process that diverts a portion of the multiplexed aggregate signal at an intermediate point, and introduces a different signal for subsequent transmission in the same position.

Drop and Insert

130

A mathematical value derived from the number and severity of leaks in the cable system.

Cumulative Leakage Index (CLI)

131

How often is a CLI test performed?

Annually

132

What 2 ways can a CLI test be performed?

ground based or an aerial "flyover"

133

How long must leakage logs be kept on file?

At least 2 years

134

At what interval is CLI monitored?

Quarterly

135

FCC regulations requires a CLI figure of merit of what number?

64 or less

136

What is the most common cause of signal leakage?

poorly installed F-connectors in the drop

137

Carrier-to-beat rations greater than ______ are far enough below desired carrier level to be of little concern to the average viewer.

57 dB

138

This appears when ingress allows a locally broadcast TV channel's signal to enter the TV along with the channel's signal supplied by the network.

leading ghost

139

This is usually caused by a reflection on the cable system caused by poor directivity at the tap or device feeding the set.

following ghost

140

In cable systems it us usually caused when the same channel from two (or more) different TV stations is received by the same antenna.

Co-Channel Interference

141

Carrier-To-Noise Rule 1

If the input level (in dBmV) numerically equals an amplifier's NF, the output C/N will always e 59.2 dB.

142

Carrier-To-Noise Rule 2`

For each dB the input level is raised above the amplifier's NF, the output C/N improves by an equal amout above 59.2

143

Carrier-To-Noise Rule 3

C/N at the output of a single amplifier is always worse than that at the input by an amount equal to the amplifier's NF.

144

These are an undesired change in the waveform of a signal.

Distortions

145

This is literally the "crossing" of modulation from one channel to another

Cross Modulation (XMOD)

146

For systems carrying forty or more channels, what distortion becomes visible before XMOD?

composite triple beats (CTB)

147

This appears as a horizontal bar moving from the bottom to the top of the picture

Hum Modulation

148

A primary source of hum modulation

power passing chokes used in passive devices

149

It is a source of hum modulation found in older systems.

using series regulated DC power supplies in the amplifier housings.

150

A phase modulation algorithm that is a digital modulation scheme wherein the carrier is shifted in 90-degree steps

Quadrature Phase Shift Keying (QPSK)