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2.3.1
RS-485 / RS-422 Data Transmission Settings (cont’d)
Slew rate for the data being transmitted:
Jumped*
Functional Description
JP4
2 & 3
Slew rate set to 10Mbps
* Note
: Factory setting. Do not change.
TABLE 3: JP4 JUMPER SETTINGS
2.3.2
Fiber Optic or Copper Transceiver Network Settings
A new feature to the VERSITRON class of Modems is the ability of the F270X and F271X Series
Modems to multiplex data (RS-485 or RS-422) and analog (Telephone audio signal) onto a fiber OR copper
network, depending on the application. Figure 1.4 shows an example for a copper and fiber network circuit.
The selection for a copper (4-wire twisted pair) or a fiber optic interface is accomplished by the following dip
switch settings:
Position
Copper Interface
Fiber Interface
SW2-1
On
Off
SW2-2
Off
On
SW2-3
On
Off
SW2-4
Off
On
TABLE 4: SW2 SWITCH SETTINGS
2.3.3
Interface Impedance Selection
The telephone / analog frequencies look into impedance known as the line impedance. In the USA and
North America it is about 600
Ω
. In Europe and the Far East it is usually 900
Ω
. F270X and F271X comply
with both standards, depending on the jumper settings. These settings are as follow:
Jumper
Jumped*
Functional Description
JP1
1 & 2
900
Ω
line impedance
JP1
2 & 3
600
Ω
line impedance
JP2
Jumper off
/
removed
900
Ω
line impedance
JP2
Jumper on
/
in
600
Ω
line impedance
*
Note:
Factory Setting: JP1: (2 & 3 are jumped) and JP2: (Jumper on / in)
TABLE 5: LINE IMPEDANCE JUMPER SETTINGS
