3.1.1 Interface Driver Board
The Model 2703RC-A Series features changeable Interface Driver
Boards that allow a wide range of DTE interface connections.
Supported interfaces are V.35, EIA-530, and X.21. The Interface
Driver Board plugs onto a 40 pin header (2 rows of 20 pins) on the top
side of the 2703RC-A PC board (See Figure 3, below).
Your 2703RC-A comes with an Interface Driver Board already
mounted on the board. If you wish to change the electrical interface of
the 2703RC-A, you must change the Interface Driver Board (See
Appendix B for Model Numbers).
Follow the instructions below to change the Interface Driver Board:
1. With the 2703RC-A pulled out of the rack or clusterbox chas-
sis, locate the driver board on the top of the 2703RC-A front
card.
2. Lift the interface board gently off of the PC board.
3. Locate the correct interface on the bottom of the driver board.
For example, V.35 interface board is marked “THIS SIDE UP
FOR V.35” on one side of the board other side .
4. Plug the interface board into the 20 pin header socket with the
appropriate interface pointed UP and with the arrow pointing
toward the front panel of the Model 2703RC-A PC board.
5. Push the Interface Driver Board gently onto the socket and re-
install into the rack or cluster system.
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Figure 3. Closeup of Model 2703RC-A Interface Driver Board
FRONT THIS SIDE UP FOR V.35
3.2 REAR CARD CONFIGURATION
The Model 2703RC-A has two rear interface card options:
1. Model 1000RCM703120 - 120 Ohm (modular) network and
female (DB-25) terminal (Supports V.35, EIA-530, and X.21).
2. Model 1000RCM70375 - 75 ohm (dual BNC) network and
female (DB-15) terminal (Supports X.21 Only).
Please refer to the instructions below to configure the rear cards.
3.2.1 CONFIGURING THE 1000RCM703120 REAR CARD
The Model 1000RCM120 DB25/RJ45 Ohm rear card has five con-
figuration jumpers (LK1 - LK5). Figure 4 (below) shows the locations
of the jumpers on the 120 Ohm rear card.
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Figure 4. Jumper Locations for the Model 1000RCM703120 Rear Card
LK4
LK3
LK2
LK1
LK5
DB-25
Connector
RJ-45
Connector
