CTC Union ETU01-Plus, User Manual

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Chapter 4. Test & Diagnostics
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4.6 Remote Digital Loop Back
This test is activated by depressing the "Rem loopbk" push button. The test
determines the performance both of the local and the remote ETU01-Plus units, as
well as their interconnecting lines. The remote digital loop back test consists of
providing a loop back at the remote ETU01-Plus (see Figure 4.4).
A system test may be performed by first depressing the remote loop back switch,
then depressing the pattern switch. The test pattern will be generated, sent out the
E1 link and looped back by the remote unit. If no errors are indicated by the error
LED, the link test has been successful.
Figure 4.4 Remote digital loop back
4.7 Quick E1 Self-test
Use this "Quick Test" to check the E1 circuits for a standalone unit.
Set DIP switches all OFF, except:
DIP SW5-1 ON (Internal Osc. Timing)
DIP SW6-1 ON (75 Ohm for Coax Cable)
DIP SW6-8 ON (enable pushbuttons)
Connect the E1 Tx to E1 Rx with a single coaxial cable.
Press the Pattern/test switch.
Test LED will remain Red. The E1 Tx and Rx circuits will be tested and pass if the
'Error' LED is not lit.
Without any coaxial cable connected, the logic circuits can be tested by pressing
both the 'Pattern' and 'Loc ana loopbk' switches. No 'Error' should light.
E1
ETU-01
Rem loopbk
Depressed
LOCAL
DATA
TERMINAL
CLK
DATA
DATA
CLK
XMTR
RCVR
XMTR
RCVR
Remote Unit
ETU01-Plus