Patton electronic 2702 G.703 Clock Mode Settings SW3 SW4, Clock Modes, DTE Interface Connection

Switch SW3 and SW4: Clock Mode

SW3 is used to along with SW4 to determine the clock mode. For example the Model 2702 can be set to external clock mode by setting both SW3 and SW4 to the on position. Please refer to the Clock Mode chart below for the desired settings.

CLOCK MODE SETTINGS

SW3	SW4	Clock Mode
Off	Off	Network (Default)
Off	On	Internal
On	On	External
On	Off	Network

CLOCK MODES

Network Clock Transmitter timing is derived from the received line signal.

Internal Clock Transmitter clock is derived from an internal clock source

External Clock Transmitter timing is derived from the local DTE device. A 2.048 MHz timing signal must be present a at the external clock pin U and pin W on the M/34 connector.

Note: When using the 2702 as a high-speed short range modem, one unit of the link must be configured in either internal or external clock, and the other end must be configured for network clock mode, or both units could be either Internal or External Clock. But both units cannot be network clock mode in SRM applications

4.0 INSTALLATION

The Model 2702 is equipped with DTE, network, and power interfaces. This section briefly describes connection to each.

4.1 DTE INTERFACE CONNECTION

The DTE/DCE interface is a V.35 DCE presented as an M/34 male connector. This interface is designed to plug directly into a DTE inter- face (See Appendix D for V.35 interface pin assignments).

4.2 NETWORK INTERFACE CONNECTION

The Network Line Interface is an eight position keyed modular jack configured as a RJ-48C. This interface will need to be configured to match the line parameters (i.e. framing, line coding, etc.) supplied by the central office.

RJ-48C Jack				Signal Name
	1	1		(RX) Receive (Ring)
		2		(RX) Receive (Tip)
	2	3		Shield
	3		4	(TX) Transmit (Ring)
	4
			5	(TX) Transmit (Tip)
	5
	6	6		Shield
	7	7		No connection
	8	8		No connection

Figure 3. Model 2702 twisted pair line interface.

NOTE: If the Model 2702 is being used for private short range modem applications, the twisted pair cable connected to its port will need to be a cross-over cable, and should be configured as shown below. See Appendix D for Interface pin assignments.

SIGNAL	PIN NO.	PIN NO.	SIGNAL
RX Data (Ring)	1	4	TX Data (Tip)
RX Data (Tip)	2	5	TX Data (Ring)
TX Data (Ring)	4	1	RX Data (Ring)
TX Data (Tip)	5	2	RX Data (Tip)

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