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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 |
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Framing Format | Off | Off | ESF* | |
On | Off | SF | ||
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| Off | On | |
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| On | On | |
Line Code Format | ..... Enables Bipolar | |||
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| operation for the T1 carrier system, or Alternate Mark Inversion (AMI). This option | ||
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| must be configured identically with all other T1 network equipment on this circuit. | ||
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| On | ............... | AMI |
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| Off * | B8ZS | |
CSU Loopback | Enables the CSU Loopback Function. Unit will respond to CSU loopback sent from a | |||
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| remote network device or test equipment. | ||
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| Off * | Enabled | |
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| On | ............... | Disabled |
| Timing Mode | Determines clock source for TA 750. | ||
Timing A | Function | |||
Timing B | Off * | Off * | Loop timing: Derives timing from T1 | |
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| On | Off | External timing: Derives timing from external BITS clock |
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| Off | On | Local timing: Clock generated from internal timing source |
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| On | On | Loop timing: Derives timing from T1 |
| DS1 Attenuation | Selects attenuation to set receiver sensitivity in decibels (dB). | ||
LBO A | Setting | |||
LBO B | Off * | Off * | 0 dB / | |
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| On | Off | |
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| Off | On | |
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| On | On | |
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| (Note: additional LBO settings can be provisioned through the menu interface.) |
* Denotes factory default settings.
Section | 3 |