Case Communications syncro 1496, Reference Manual

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rate information. The lower the value the better the quality of
service, as indicated below.
Value Performance
1-2 Very good
2-4 Good
4-6 Fair
6-10 Bad
10-12 Very Bad
12-15 Unusable
13 Signal Noise:
This is a measurement of the difference in level of signal, to the level
of random noise on the communications line, expressed in dB. Each
modulation scheme has a different minimum level of signal to noise
at which it will perform satisfactorily. For example, V.32 will
require a minimum level of about 20 dB, whereas V.33 will require a
minimum level of about 27 dB. These figures will vary with different
line types and speed of transmission. In general the larger the figure
the better; a very low signal to noise will indicate a poor
communications line.
14 Estimated BER (Bit Error Rate)
This is an estimation of errors that can be
expected when transmitting data, expressed as 'greater than' or 'less
than' a figure of 10
-n
, n being a value between 1 and 8.
Example: A BER of <10
-8
will indicate a bit error rate of less than 1
bit in every 100 million bits sent; a BER of <10
-7
would indicate a bit
error rate of less than 1 bit in every 10 million bits sent, and so on
down to <10
-1
which indicates a bit error rate of greater than 1 bit in
every 100 bits sent.
X450-310851 Issue 2 7-10 Rev.0