Cisco Headend System Release 2.5 사용자 가이드
78-738186-01 Rev B
DHCT Status Reporting Utility
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Understanding the Interface,
Continued
High or Low Transmit Levels
Even though DHCTs can transmit successfully at levels higher than 55 dBmV or
Even though DHCTs can transmit successfully at levels higher than 55 dBmV or
lower than 25 dBmV, the fact that these DHCTs exist on a system may indicate a
serious configuration problem. Occasionally, the entire population of DHCTs
assigned to a specific QPSK modulator or demodulator may transmit at levels that
are too high or too low. The system can support two-way communications with a
portion of these DHCTs; other DHCTs assigned to this modulator or demodulator
may transmit at levels that are too high or too low to even be recognized.
Consider this rule of thumb: if 3 percent or more of successfully responding DHCTs
Consider this rule of thumb: if 3 percent or more of successfully responding DHCTs
respond at levels higher than 55 dBmV or lower than 25 dBmV, you can assume that
there are other DHCTs responding with signals too high or too low to be recognized.
Note: You can see an illustration of this concept in the graph under Examples of
Note: You can see an illustration of this concept in the graph under Examples of
Systems Needing Recalibration, under the DHCT Transmit Level Saturation
Report heading of Section E.
System operators can use the information provided by the DHCT Status Reporting
System operators can use the information provided by the DHCT Status Reporting
Utility to identify modulators or demodulators associated with non-responding
DHCTs. System operators can then take measures to adjust transmit levels so that
they conform with Cisco recommendations. This issue is discussed in more detail in
DHCT Transmit Level Saturation Report in Section E.
Section 3 — Total # of InService 2 Way Non-Responders
The Total # of InService 2 Way Non-Responders section is referenced by number 3.
This short section summarizes the total number and percentage of DHCTs that have
two-way communication capability, but these DHCTs do not respond to poll
requests from the DHCT Status Reporting Utility.
Section 4 — Main Menu Options
The Main Menu Options section is referenced by number 4. This area lists the
various options you can use when you run the DHCT Status Reporting Utility.
Subsequent chapters in this guide provide detailed instructions for running each
option.
Note: The Help option of the DHCT Status Reporting Utility briefly describes each
Note: The Help option of the DHCT Status Reporting Utility briefly describes each
of the options included in the utility. Go to The DHCT Status Reporting Utility
Help Option, next in this chapter.