Tahoe 671, Руководство пользователя

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3.9. Language selection
After pressing “Enter” the language used on the LCD and the
serial console may be changed.
3.10. Write configuration to EEPROM
Every change to the configuration will be lost after reboot or
power off unless the settings are written to the EEPROM. After reaching
this option just press Enter to save them.
3.11. Connection reset
After pressing Enter the G.shdsl link will be disconnected and
negotiated again.
3.12. Modem reset
After pressing Enter the whole modem is rebooted. If some
settings were not saved to the EEPROM, they will be lost.
3.13. Line parameters
The “Esc” button returns to the main screen (with modem type,
throughput and link state). While having this screen displayed, you
may press Enter to display line attenuation in dB (proper value appears
only after the line synchronizes):
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Pressing Enter again will show so-called Noise Margin (or Signal-
Noise Ratio). This is the difference between the useful signal and the
background noise. It may be used to estimate, how much the line rate
may be increased without causing any problems with the
synchronization.
When the NMR is less than 0 dB modems will be unable to bring
the link up.
It is the best practice to keep the NMR equal to or higher than 7-
8 dB, so the error rate will be unnoticeable. Otherwise the packets will
be lost due to bit errors and the retransmission would be necessary,
thus decreasing the overall effective throughput.
Pressing Enter again will return to the main screen with the
throughput and modem state.
3.10
3.9
Connection reset
(press Enter)
Modem reset
(press Enter)
Line attenuation:
12.5 dB
Noise margin:
6.0 dB
3.11
Language:
English
3.12
Write config
to EEPROM
3.13