
NPE O
NPE 1
MICROPROCESSOR
PORT
1/0
CIRCUIT
GROUND
DETECTOR
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| CIRCUIT | |||||||
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| 0 |
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| T.O |
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| CODEC |
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| HYBRID |
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● |
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| R.O | |||
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| ❘ |
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| ❘ |
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| ❘ |
| T.3 | ||
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| CIRCUIT |
| R.3 | ||
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| 3 |
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| T.4 | |||
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| PORT |
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| CIRCUIT | R.4 | |||||||
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| 4 |
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●❘
❘T.7
PORT
CIRCUIT
R.7
7
\
TO
CENTRAL
OFFICE
/