Operational Capabilities; Circuit Operation; Loop Start Operation; On-Hook (Idle) Condition - ADC PG-Flex FLC-704 Manual

Operational Capabilities

O C
PERATIONAL
The FLC-704 List 1A CU provides eight loop start or ground start POTS interfaces to the CO switch. The unit
performs the interface function between the analog POTS circuit and the internal digital pulse coded modulation
(PCM) bus. In addition, each CU:
• detects forward battery
• detects ringing voltage
• detects reverse battery
• detects Tip ground and Tip open
• detects 12 kHz or 16 kHz meter tone
• detects a subscriber test access signal
• provides loop closure
• provides grounded ring lead
• converts analog signals to and from 64 kbps A-Law PCM digital format
C O
IRCUIT PERATION
The following paragraphs define the FLC-704 circuit operation when using loop start for subscriber lines or
ground start for PBX lines. Each FLC-704 circuit has an associated LED that indicates when the line is off-hook,
on-hook (idle), ringing, or under test (see

Loop Start Operation

The following section summarizes the loop start sequences for on-hook (idle), subscriber inititated outgoing calls,
subscriber received incoming calls, and busy conditions.

On-hook (Idle) Condition

Loop start idle condition is a Ring-lead negative and Tip-lead positive from the CO with the same condition out
of the RT toward the subscriber (see
Table 2. Circuit Interactions for an Idle Condition (Loop Start)
Operation
Circuit Idle
4
APABILITIES
Table 1 on page 2
Table 2 for circuit interactions).
CO Switch FLC-704 COCU
⇒
No ringing
⇐
On-hook
January 6, 2003
for front panel LED definitions).
FRC-754 RTCU Subscriber
⇒
No ringing
⇐
On-hook
SCP-FRC754-042-03H
FLC-704 List 4B