Motorola MTR2000 T5544 Instruction / Field Service Manual page 197

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FUNCTIONAL THEORY OF OPERATION
The following theory of operation describes the operation of the WIB circuitry at a functional level. The informa-
tion is presented to give the service technician a basic understanding of the functions performed by the module
in order to facilitate maintenance and troubleshooting to the module level. Refer to Figure 3 for a block diagram
of the 2-wire voice signal path, and to Figure 4 for the 4-wire voice signal path.
Functional Overview
(Refer to Figures 3 & 4)
68P81096E28-C
09/30/05
Introduction
As mentioned previously, the WIB serves as the interface between the cus-
tomer analog telephone lines and the serial PCM data signals of the station
equipment. In general, the WIB routes all voice and/or remote control sig-
nals between the station equipment and the landline equipment (e.g., a
control center, modem, etc.).
As shown in the block diagrams in Figures 3 and 4, the WIB contains one
2-wire audio circuit and one 4-wire audio circuit. Also provided is imped-
ance-matching jumper fields which are used to meet various wireline
specifications.
Audio/Data Circuits
As shown in the block diagrams, each WIB contains a PCM Codec-filter,
SPI latch and associated circuitry which can be configured to provide the
following signal paths:
• 2-wire voice audio/data from landline to station, and from station to
landline
• 4-wire voice audio/data from landline to station, and from station to
landline
These audio signals may include Tone Remote Control signals
CLN1204 Wireline Interface Board
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