Patton electronic 2707C, 2707D Connecting The Serial Port, Connecting to a “DTE” Device

Connecting the Twisted Pair (120 Ohm) to the G.703 Network

The Model 2707 is equipped with a single RJ-48C jack for connections to a 120 Ohm twisted pair G.703 network interface. If your G.703 network terminates via RJ-48C, use Figure 4 below to connect the 120 Ohm G.703 network channel.

Figure 4. G.703 120 Ohm Connection

4.2 CONNECTING THE SERIAL PORT

The Model 2707/C and D supports V.35, X.21 serial port connections. This section describes how to connect the serial ports to your terminal equipment.

Connecting to a “DTE” Device

The serial port on the 2707/C (V.35 version) is hard-wired as a DCE. Therefore these modules “want” to plug into a DTE such as a terminal, PC or host. When making the connection to your DTE device, use a straight through cable of the shortest possible length—we recommend 6 feet or less. When purchasing or constructing an interface cable, please refer to the pin diagrams in Appendix C as a guide.

Connecting to a “DCE” Device

If the Model 2707 serial interface is hard-wired as a DCE (all except the X.21 version), you must use a null modem cable when connecting to a modem, multiplexer or other DCE device. This cable should be of the shortest possible length—we recommend 6 feet or less.

Configuring the X.21 Interface (2707/D)

The serial port on the X.21 interface is default wired as a DCE, but may be switched to a DTE. This is done by reversing the orientation of the DCE/DTE strap, as described below:

To reverse DCE/DTE orientation, remove the top case. Refer to “Open- ing the Case” on page 9.

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