Lesson 5: Troubleshooting Digital Video Service
When replacing a splitter to resolve a digital TV (DTV) service problem, what does confirming the splitter output levels before attaching the output connectors do?
Confirmation reinforces the technician's confidence that the problem will be resolved by replacing the splitter. Confirmation ensures the splitter output connector threads are intact. Confirmation reinforces the technician's confidence that the problem will be resolved by replacing the splitter. Confirmation removes grease or any other contaminants from the splitter output connectors. Confirmations verifies the device is a splitter and not a house amplifier or filter.
During which step of the six-step troubleshooting process for a digital TV (DTV) service problem are quadrature amplitude modulation (QAM) channel measurements typically taken?
Diagnosing symptoms. Resolving the problem. Isolating elements. Diagnosing symptoms. Identifying the problem.
After a digital TV (DTV) service problem has been analyzed and possible causes considered, what is accomplished by isolating the various network elements?
It narrows the scope of likely problem sources. It narrows the scope of likely problem sources. It minimizes network disturbances. It enables measurement of signals. It shows the customer that something is being done.
Because the spectral density of a quadrature amplitude modulation (QAM) channel is much higher than that of an analog TV channel, what is done to ensure equal power in all channels in a network with analog and digital modulation channels
Operate the analog TV channels at higher amplitude level than the QAM channels. Reduce the bandwidth of the QAM channels from 6 MHz to 3 MHz. Maintain a ratio of 12 analog channels to one QAM channel. Keep the QAM channels at the higher frequencies where their amplitude is attenuated more than the analog channels. Operate the analog TV channels at higher amplitude level than the QAM channels.
When troubleshooting a digital TV (DTV) authorization issue, what can be verified using the set-top box (STB) diagnostic page?
STB reception of authorization message data. The customer account status. The STB serial number. Transaction history going back the last 6 months. STB reception of authorization message data.
Which type of set-top box (STB) operates more like Data Over Cable Service Interface Specification (DOCSIS) cable modems with return channels on the same frequencies used for cable modems?
STB with DOCSIS Set-top Gateway (DSG) client software and embedded DOCSIS modems. DOCSIS cable modem gateways. Digital terminal adapters (DTA) with embedded DOCSIS modems. STB with DOCSIS Set-top Gateway (DSG) client software and embedded DOCSIS modems. The first generations of digital STB with RF return.
Which of the following characterizes the successful troubleshooter?
Someone with an inquisitive and relentless desire to solve and fix problems. Someone that is pleasant, organized, and patient. Someone with an inquisitive and relentless desire to solve and fix problems. Someone that is confident making quick decisions without talking to the customer. Someone that is focused on closing the work order and moving to the next assignment.
What does a set-top box (STB) diagnostic page of a quadrature amplitude modulation (QAM) channel showing signal-to-noise ratio (SNR) near or below 30 dB indicate?
The QAM channel quality is on the edge for reliable reception, and the source of the problem is likely in the distribution network or customer premises. The QAM channel quality is acceptable and the technician can try selling the customer new services. The QAM channel quality is on the edge for reliable reception, and the source of the problem is likely in the distribution network or customer premises. The QAM channel quality is acceptable and the problem is likely the customer's TV. The QAM channel quality is being compromised during capture and processing.
Which of the following digital TV (DTV) trouble calls could have been avoided with customer education about the product?
The digital set-top box (STB) overheats. Intermittent "freezing" on all DTV channels. Unable to order video-on-demand (VOD) programs. The set-top box (STB) is unauthorized for service. The digital set-top box (STB) overheats.
What must a technician be aware of when analyzing a digital TV (DTV) problem?
There is frequently more than one contributor to a specific DTV service problem. There is frequently more than one contributor to a specific DTV service problem. How the DTV service problem relates to analog TV service. That the digital set-top box (STB) can be eliminated as the likely cause of the problem. There is only one customer reporting this problem.
