Chapter 4
General Information and Features
57
4.12
Line Status Monitoring
In order to let users manage transmission conditions, the TAINET Network Series
Modem provides a signal quality displayed at right lower corner of the screen. It
ranges from 0 to 9. The following shows the relationship between the displayed
number and bit error rate (BER).
9 --
< 10 ^ -9
8 --
< 10 ^ -8
7 --
< 10 ^ -7
6 --
< 10 ^ -6
5 --
< 10 ^ -5
4 --
< 10 ^ -4
3 --
< 10 ^ -3
2 --
< 10 ^ -2
1 --
< 10 ^ -1
0 --
NO Connect
Basically, 10^-5 to 10^-6 is the basic required bit error rate. If this condition is not
achievable; leased line users should report to telephone company, however, it is
better for dial line users to try the dial again.
There are some real time line condition information which may help you judge the
line quality:
1. Transmitted signal level
Tx level = -10 dBm
2. Received signal level
Rx level = -25 dBm
3. Signal to noise ratio S/N Ratio = 35 dB
4. Received frequency shift F-Shift = 0.2 Hz
5. Far-end frequency shift
F F-Shift = 1.7 Hz
6. Round trip delay
Delay = 560 ms
7. Phase jitter P J = 1 Degree
8. Far-end echo level F Echo = -40 dB
9. Terminal mode
DTE = 19200 ASY 10