3
RJ-45 Jack and Terminal Block Descriptions
Shielded RJ-45 Jack:
· Pins 1 and 2 are the balanced inputs. The balanced signals
are converted to an unbalanced signal on the center
conductor of the TX Out coax connector.
· The unbalanced signal from the RX In coax connector is
converted to balanced signals on pins of the RJ-45.
· The shield of the RX In connector may be connected to RJ-
45 pin 6 by jumper JP2 (on).
· The shield of the TX Out connector is always connected to
the shield around the RJ-45 connector. This connection may
also be connected to RJ-45 pin 3 via JP1 (on).
Terminal Block:
· Has a 4 pin terminal block for a twisted pair connection.
· The 460M has male coaxial connectors (i.e., center
conductor is a pin) and the 460F has female coaxial
connectors (i.e., center conductor is a receptacle).
4
CONFIGURATION
NOTE: The Model 460-TBP does not require configuration; go to
section “INSTALLATION” on page 2. The following section
describes configuring the Model 460. The Model 460 Series are pre-set
to work in most applications without additional configuration. The only
parameter that is user-configurable is the shield connection between
the 75 Ohm coax and 120 Ohm interfaces. The diagram on the
following page shows how the shield is connected between the modular
jack and dual BNCs. Removing the jumper breaks the connection.
The Model 460 is most often used to bi-directionaly convert CPE
twisted pair terminations to CPE coaxial terminations.
RJ-45 (120 ohm)
Jumper
Coax BNC (75 ohm)
Pin 3 (TX Shield)................ JP1......................TX Out Shield
Pin 6 (RX Shield).................JP2........................RX In Shield
The factory setting leaves both jumpers JP1 and JP2 (see figure
above) in place, thus passing both shield connections through. To break
one or both of the shield connections, follow the instructions on the next
page.
1)
Insert a flat blade screwdriver into the slot on the side of
the Model 460 case and twist. The case will pop open,
exposing the PC board.
2)
Holding the PC board with the modular jack facing left,
locate jumper JP1 toward the top of the board and JP2
toward the bottom of the board. Remove the desired
jumper(s) to break one or both shield connections.
NOTE: Do not lose the jumper(s).
3)
Re-align the case halves and end inserts and snap the case
halves back together.
Gaithersburg, Maryland
Model 460F-TBP
G.703 Balun
S/N:9912130009 Lot: 00774
RX In
TX Out
RJ-45 connector
TX Out connector
Rx In connector
TX Shield
RCV
XMT
XMT
RCV
RX Shield
XMT
RCV
XMT
RCV
1
2
3
4
5
6
7
8
Twisted-
pair
CPE
RX In
GND
Network
Network
Network
Network
Network
Network
Signal
Signal
GND
Shielded RJ-45 Jack
JP1
JP2
TX Out
Pair 1
Pair 2
Twisted
Pair
Equip-
ment
Summary of Contents for 460 SERIES
Page 5: ......
