2.4 Setting DSL rate
Fixed rate value is set by dial switch RATE (figures 2 and 4). One of 16 fixed
data rates have to be selected by the dial.
2.4.1 Setting DSL rate for remote modem
This feature is available only for modems with firmware version 2.5 or higher.
The SET2 switch has the following meaning:
•
if SET2 is OFF, the rate is set manually at both ends of the line. (I
this case modem uses Annex A for compatibility with firmware
version 2.4 and lower)
•
if SET2 is ON, the DSL rate is set by the dial switch RATE of the
“master” modem. (In this case Annex F is used.)
The SET2 switch must be set to the same position for both modems.
To operate properly peer-to-peer, the modems settings should
match each other! Do not forget to configure the remote
modem beforehand!
2.4.2 Rate selection guidelines
Before setting the data rate you should have known the performance of the
line the modems are intended for. If the line performance is unavailable, apply
the following technique to select the proper data rate:
•
Measure resistance of the line. To do this, make short-circuit on either
line side and attach an ohmmeter to another one. Then determine a
maximum rate providing reliable communication by table 2.
•
Switch carefully the dial to the required position with a screwdriver.
Reboot both modems to activate the new settings. If the remote rate
setting is used (SET2 is ON), change the “master” modem rate only. Link
activation takes up to 2 or 3 minutes to succeed.
•
If the link is not activated (the DSL LINK LED is not getting light) during
the mentioned time, set a smaller value on the rate dial and do the next
attempt to activate the link.
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