CTC Union MUX128, Installation And Operation Manual

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Chapter 1: Introduction
7
1.6 Loop back Diagnostics
The
MUX128/2*64
features V.54 diagnostic capabilities
for performing local loopback and BERT testing. The
operator at either end of the G.703 lines may test the
MUX128/2*64
in the digital loopback mode. The loopback
function is controlled by push-button switches, located on the
MUX128/2*64 front panel.
When the “Test” push-button is activated, the unit
generates a 511 test pattern, according to ITU, for direct end-
to-end integrity testing. The Error indicator flashes for each
bit error detected. Operation is described in Chapter 2.
1.7 Timing Considerations
Multiple clock source selection provides maximum
flexibility in connecting both the G.703/64K link and user data
interface. The G.703/64K link may be clocked from the
recovered receive clock, from the user data port or from the
internal oscillator.
The MUX128/2*64 has the flexibility to meet the timing
requirements of various system configurations. The timing
mode for the G.703/64K link and the user channel, is selected
by DIP switch setting.