Multitech MMH900, User Manual

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81
Chapter 5 - Commands
$LA0: Off (default)
$LA1: Japan Level
$LA2: U.S. Level
$LD0-2 Link Delay
This command enables cable equalization that
compensates for delay distortion in the public
telephone network in a similar manner to the
amplitude done by the Link Amplitude command.
$LD0: Off (default)
$LD1: Japan Level
$LD2: U.S. Level
$CQ0-3 Cable Equalization
The Cable Equalization command incorporates a
compromise equalizer that minimizes the effect of
how much direct wiring there is in the modem’s
network. The amount of copper wiring carrying an
analog signal affects the data transmissions so that
the lower frequencies are attenuated less than the
higher frequencies. The longer the cable the more
pronounced the effect. Each of these commands will
compensate for the effect according to its listed
distance. Unless a problem with modem retraining
or a high error rate occurs, no equalization will be
necessary.
$CQ0: 0.0 km (Default)
$CQ1: 1.8 km
$CQ2: 3.6 km
$CQ3: 7.2 km
$RL0-1 Receive Level
The Receive Level Command selects the sensitivity
level of the modem to incoming transmissions. The
level settings are in dbm increments. The -43 dbm
level is the default condition which makes the unit
able to receive very low level signals. As the
sensitivity becomes less, the modem requires a
stronger signal. This parameter should only be
changed under the direction of service personnel.