General DataComm 076P054-001, Руководство по установке и эксплуатации

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Introduction and Specifications SpectraComm SRM-6 Overview
1-4 SC SRM-6 Multiplexer 076R176-000
Installation & Operation Manual Issue 1
Timing
In 4-wire, leased private line modem applications that use aggregate data rates of 19.2, 28.8, or 33.6
Kbps, the SRM-6 gets its transmit timing from the SC V.F28.8 modem or one of the DTEs. One
modem is configured for Internal or External transmit timing, with the modem on the other side
configured for Receive transmit timing. In DDS network applications requiring aggregate data rates
of 56 and 64 Kbps, the SRM-6 gets its transmit timing from the DSU that is configured for Receive
transmit timing.
Note
For more information on configuring transmit timing in the modem or DSU, refer to the corresponding
manual listed inside the front cover of this document.
Figure 1-2 Terminal Timing in a SRM-6 System
4-Wire Leased
Private Line
DTE
SRM-6
MODEM
REMOTE SITE
Chan. 1
Channel 1
Tx Clock
set to TT
(Pin 24)
External
Timing
(Pin 24)
Aggregate
Tx Clock set to
Channel 1 TT
(Pin 15)
Aggregate
Tx Clock
set to ST
SRM-6
DTE
Chan. 1
Channel 1
Tx Clock
set to ST
Receive
Timing
Provides
Clock
CENTRAL SITE
MODEM
Receive
Timing
(Pin 15)