Lanex MD-76, Operating Manual

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E1/G.703 F
IBER
O
PTIC
M
ODEM
O
PERATING
M
ANUAL
IOA76-1F 16 May 2009
4.4 E1/G.703 linear signal connection
4.4.1 TM-76 and MD-76
E1/G.703 interface input and output signals of TM-76 and MD-76 devices are transmitted
via two screened symmetric cables of 120
Ω
impedance or one double screened cable
of the same impedance.
The following rules should be observed to meet the requirements concerning noise
emissions. Symmetric cables should be connected using DB-9 plug equipped with a metal
or metal plated casing (shield) and the cable screen should be connected to the casing over the
whole circumference. It is insufficient just to connect the screen to the "structural earth"
terminals on the E1/G.703 120
Ω
interface socket.
The E1/G.703 120 linear module socket outputs
Ω
are described in 05.
Table 5. Description of TM-76 and MD-76 E1/G.703 120 interface outputs
Ω
Pin No. Description of outputs
1 Not connected
2 TX_A Linear signal output
3 GND
4 GND
5
RX_A Linear signal input
6 Not connected
7 TX_B Linear signal output
8 GND
9
RX_B Linear signal input
4.5 Connection to VT100 terminal or a computer with the installed Lanwin
management software.
TM-76 device is equipped with RS-232 interface enabling modem management from
the level of VT100 terminal or using the Lanwin software. The interface is described in 06.
Table 6. Description of RS-232 / V.28 DCE connector outputs (RJ-45 type)
Pin Description
4 SGND
6 Tx
OUT
5 Rx IN
RS-232 cable should be used to connect TM-76 modem to a terminal. Table 7 specifies the
required list of cable connections.