Meridian America 61 Benutzerhandbuch
PRACTICE 553-2201-183
4. CHARACTERISTICS
FUNCTIONAL
Common Features
4.01
The following features are provided:
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balanced terminating impedance
Unique Features
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-48 V through a battery feed resistance and ground
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supervise the loop current to determine on-hook/off-hook status
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ringing current to the loop
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isolation of foreign potentials on the loop from the transmission and
signaling circuit
signaling circuit
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conversion from a to a 4-wire transmission path
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analog-to-digital and digital-to-analog conversion of transmission
signals
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common multiplexing’ circuit to interface with the peripheral bus
signaling channel
.
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retime the digital signals received from the peripheral bus
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decode address information received from the peripheral bus to
enable individual line circuits during selected time slots
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control the disconnection timing of ringing current to the loops to
avoid switching during current peaks.
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4.02 The various special versions of the
line pack have
additional features as follows:
4.03
and QPC292 OPX Line packs:
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serve lines up to a maximum loop resistance of 1400
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serve Dataphone sets
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have line-to-line insertion loss of 1
4.04 QPC494 and QPC558 Message Waiting Line packs:
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provides connection of -150 V in a steady or 1 Hz flash rate to
activate the Message Waiting lamp on the telephone
activate the Message Waiting lamp on the telephone
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provides for one Message Waiting lamp per line
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maintain all Message Waiting lamps off and do not allow phones to
ring during power-up sequence.
ring during power-up sequence.
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