TOA Electronics EX-16 - Manual (Page 35)

3. T-Line and R-Line are shorted or mixed up.
Shorted or mixed up
3-1 A can not dial.
3-2 Conversation is impossible between
stations.
3-3 When B dials A, noise will be heard at
B immediately after the calling tone.
4. T-Line and R-Line are connected conversely.
Symptom: 4-1 A can not dial.
4-2 Conversation is impossible between
stations.
4-3 When B dials A, noise will be heard at B.
(B) T-Line
R-Line
EXCHANGE
T-Line
R-Line
Conversed
(A)
R-Line
T-Line (A)
EXCHANGE
R-Line
T-Line (B)
Symptom:
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