General DataComm 551 Operating And Installation Instructions page 106

EQUIPMENT
TPG = TEST PATTERN GENERATOR
FIGURE 4-12. DS1 REMOTE TEST WITH LINE LOOPBACK AND SELF-TEST
EQUIPMENT
TPG = TEST PATTERN GENERATOR
FIGURE 4-13. DS1 REMOTE TEST WITH TEST LOOPBACK AND SELF-TEST
TPR
TPG
LOCAL CSU
TPR
TPG
LOCAL CSU
T1
NETWORK
REMOTE CSU HAS LLB ENABLED
TPR = TEST PATTERN RECOGNIZER
T1
NETWORK
REMOTE CSU HAS TLB ENABLED
TPR = TEST PATTERN RECOGNIZER
TESTS
EQUIPMENT
AIS
EQUIPMENT
AIS
4-15