User manual

Chapter 5. Configuration Menu
5-6 TDU 120e User Manual 61202156L1-1
Internal Timing
The TDU 120e is the source of timing. The TDU 120e is
configured to use its own internal oscillator as the source of
timing. Applications include private line driver circuits
where one end is set to network and the other to internal. See
Figure 5-5.
Figure 5-5. Internal Clock Source
Secondary Timing
The secondary interface is the source of timing. The TDU
120e uses the clock derived by the secondary interface for
transmission timing. See Figure 5-6.
Figure 5-6. Secondary Clock Source
DTE
OSC
(OPTION)
Network
Interface
T1 XMIT
T1 Receive
(DS1)
Nx56/64
DTE CLOCK
DS-1
PBX