Test B: Control Unit Test - AT&T Merlin 820 Service And Maintenance Manual

TEST B: CONTROL UNIT TEST

Do this test only if the previous test indicated the trouble was not caused by the
voice terminal.
Go to the control unit and locate the Voice Terminals jacks for the voice
Step 1.
terminal on which the trouble appears and for the voice terminal with no
trouble. Switch these two cords at the control unit (see Figure 14). The
number of the Voice Terminals jacks should match the intercom
number of the voice terminals.
VOICE TERMINAL
(WITH TROUBLE)
VOICE TERMINAL
(WITHOUT TROUBLE)
Figure 14—Switching Cords at the Control Unit
103A MODULAR
JACKS
Trouble on One Voice Terminal
SWITCH
CORDS HERE
CONTROL UNIT
JACK FIELD
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