ADTRAN 750 specifications Connections, Faceplate LED, DIP Switch S1 Options

enabled, after approximately eight minutes of keyboard inactivity, the terminal times out and returns to the password login screen.

MENU NAVIGATION

To traverse through the menus, select the desired entry and press ENTER. To work backwards in the menu press the ESC (escape) key.

Connections

All TA 750 BCU connections are made through the backplane connector. With the exception of power and the V.35 connector, all of the TA 750 rear panel connectors terminate on the BCU. These include

Network T1, Clock source, Alarms, Fractional T1, and Management. Refer to the TA 750 Chassis Installation and Maintenance Practice, part number 61175001L1- 5, for additional information on rear panel connections. Table 3 describes the T1 pinout connections.

Faceplate LED

The faceplate network LED labeled NETWORK T1 provides status information for the network T1 using a color coded message format. Refer to Table 4.

Table 2. DIP Switch S1 Options

Switch	Function	Description
		S1-1	S1-3 Setting
S1-1	Framing Format	Off	Off	ESF*
S1-3	TR-08 Signaling	On	Off	SF
		Off	On	TR-08 Digroup A
		On	On	TR-08 Digroup B, C, or D
S1-2	Line Code Format	..... Enables Bipolar Eight-Zero Substitution (B8ZS) which allows for Clear Channel
		operation for the T1 carrier system, or Alternate Mark Inversion (AMI). This option
		must be configured identically with all other T1 network equipment on this circuit.
		On	...............	AMI
		Off *		B8ZS
S1-4	CSU Loopback	Enables the CSU Loopback Function. Unit will respond to CSU loopback sent from a
		remote network device or test equipment.
		Off *		Enabled
		On	...............	Disabled
	Timing Mode	Determines clock source for TA 750.
S1-5	Timing A	S1-5	S1-6	Function
S1-6	Timing B	Off *	Off *	Loop timing: Derives timing from T1
		On	Off	External timing: Derives timing from external BITS clock
		Off	On	Local timing: Clock generated from internal timing source
		On	On	Loop timing: Derives timing from T1
	DS1 Attenuation	Selects attenuation to set receiver sensitivity in decibels (dB).
S1-7	LBO A	S1-7	S1-8	Setting
S1-8	LBO B	Off *	Off *	0 dB / 0-133 ft (LBO)
		On	Off	-7.5 dB
		Off	On	-15 dB
		On	On	-22.5 dB
		(Note: additional LBO settings can be provisioned through the menu interface.)

* Denotes factory default settings.

61175012L1-5D Section 61175012L1-5, Issue 4 3