ZETRON 640 DAPT XTRA, Руководство по установке и ремонту

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Hardware Overview
26 025-9416
Table 4. Table 4. E&M Trunk Configurations
# of
Leads
Immediate
Start
Wink
Start
Lead
Supervision
Hybridized
Full-Duplex
Dual Trunk Interface in
E&M Configuration 2
ü ü ü ü
Dual Trunk 4-Wire Audio
Interface Configuration
4
ü ü ü
For a simplified configuration schematic of the E&M signaling, see “Configuration Diagrams” in
Section 11.
E&M Immediate Start
Telco, PABX, or RF/
µ
wave link equipment initiate inbound calling to the Model 640 through M-
lead signaling. When -48 V
DC
(-24 V
DC
OK) is applied to the M-lead, the loop detect line goes
low initiating pulse, DTMF, or MF detection as programmed. The dialup equipment transmits the
feed digits to the Model 640. After the dialed digits have been decoded, the E-lead is grounded,
conversation mode begins, and the calling party is prompted for their page entry.
The call is terminated when the telco equipment drops the M-lead voltage, or when the Model
640 opens the E-lead.
E&M Wink Start
Telco, PABX, or RF/
µ
wave link equipment initiate inbound calling to the Model 640 through
M-lead signaling. When -48 V
DC
(-24 V
DC
OK) is applied to the M-lead, the loop detect line goes
low. The Model 640 “winks” to the dialup equipment by flashing the E-lead to ground for
approximately 240 mS. After the wink has been recognized, the dialup equipment transmits the
feed digits to the Model 640. After the dialed digits have been decoded, the E-lead is grounded,
conversation mode begins, and the calling party is prompted for their page entry.
The call is terminated when the telco equipment drops the M-lead voltage, or when the Model
640 opens the E-lead.
Note: -5 V
DC
or -12 V
DC
M-lead detection can be obtained by removing R6 (Trunk A) or R9
(Trunk B) from the Dual Trunk 4-Wire Audio Interface board (Part No. 702-9488).
DUAL TRUNK 4-WIRE AUDIO INTERFACE BOARD
The dual trunk 4-wire audio interface card (Part No. 702-9488) is essentially a dual trunk
interface board with the telco
hybrid circuitry removed to provide separate TO TEL and FROM
TEL audio paths with no sidetone. The board is loaded with a dual matrix card (Part No. 702-
9122) for each trunk in order to provide E-lead signaling. These
must be configured for E&M
operation as described on page 22.