Administrator’s Guide

Modem Statistics

In the Modem Statistics portion of the Diagnostics section, you can view the SoundStation VTX 1000 modem performance for the last call that made use of a modem connection.

Monitoring Line Quality

TX Bit Rate

28800

RX Bit Rate

28800

SNR

+18

Round Trip Delay

30

CRC Errors

0

The statistics provided are:

Tx Bit Rate (Transmit Bit Rate) The achievable rate for sending data over a given phone line with the modem, in bits per second

Monitoring Line Quality

VTX 1000 provides text-based status indicators on the display to communicate the real-time operational details of the phone when testing line quality and negotiating wideband and narrowband connections. Below is a description of each.

1. “Line Quality Standby”

This will be displayed if the prior phone call did not use the modem. (i.e. narrow band).

2. “Monitoring Line Quality”

This is displayed during a wideband call.

3. “Narrowband Select on Poor Sync”

This will be displayed if the local

6. “Narrowband Select on CRC Level 3”

This will be displayed if the unit detects a 40% or greater CRC Error Rate consistently at our local receiver for 6 seconds.

7. “Narrowband Select on CRC Level

Guide

 

4”

Administrator’s

This will be displayed if the unit detects

 

an 80 % or greater CRC Error Rate

 

consistently at our local receiver for 3

 

seconds.

 

8. “Wideband Signal Loss Detected”

 

This will be displayed if the remote

 

VTX 1000 shut off wideband. This will

 

also be displayed if the remote side

 

hangs up.

 

SoundStation VTX 1000 Operation Manual

Rx Bit Rate (Receive Bit Rate) The achievable rate for receiving data over a given phone line with the modem, in bits per second

SNR (Signal to Noise Ratio)

A measure, in microvolts, of signal strength relative to background noise as expressed in decibels

Round Trip Delay

The elapsed round trip time for transit of a signal over the analog telephone circuit

CRC Errors

(Cyclical Redundancy Check Errors) The cumulative number of lost data packets, a good measure of the robustness of the data connection

VTX 1000 decided to fall to Narrowband because it believed the modem had lost sync due to detected errors in V.34’s so called superframe bit inversion synchronization pattern.

4.“Narrowband Select on CRC Level 1”

This will be displayed if the unit detects a 15% or greater CRC Error Rate consistently at our local receiver for 60 seconds.

5.“Narrowband Select on CRC Level 2”

This will be displayed if we detect a 20% or greater CRC Error Rate consistently at our local receiver for 6 seconds.

Restore All Defaults

When you select Restore Defaults, you will be prompted to confirm or cancel the complete elimination of all settings and data that have been entered since the phone was first installed.

Important: If you Restore Defaults, all data entered since the phone was first installed, including, but not limited to, all Settings, Audio Setup entries, Administrative Setup passcode and data, etc., is irretrievably lost.

Note: Phone Book entries and Speed Dial numbers are not lost when restoring all defaults.

Press the OK soft key to confirm that you wish to Restore Defaults, or the CANCEL soft key to return to the Diagnostics submenu without restoring defaults.

SoundStation VTX 1000 Operation Manual

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Polycom VTX1000 operation manual Modem Statistics, Round Trip Delay, Restore All Defaults