Comtech EF Data SMS-7000, Installation And Operation Manual

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SMS-7000 Modem Protection Switch Theory of Operation
Rev. 3 4–3
4.1.2 Terrestrial Data
All terrestrial data connections are provided on the face of the DSU. Each plug-in Data
Switch Module (DSM) contains a built-in breakout panel that supports a variety of
standard data and alarm interfaces (refer to Table 4-1). These interfaces can support IBS,
IDR, D&I, or custom formats.
Table 4-1. DSM Interfaces
Data J1 — V.35 Data/EIA-232-C Data
J6 — EIA-422/MIL-STD-188 Data
J3 — G.703 Balanced
G.703/Drop & Insert Unbalanced 25-pin D
37-pin D
15-pin D
4 Coax
G.703/Drop & Insert
Unbalanced CP1 — SD/DDI
CP2 — RD/IDO
CP3 — DDO
CP4 — IDI
J5 — ADPCM Audio or 64K OH Data
CP5 — External Clock Unbalanced
J4 — Engineering Service Channel
J2 — Alarms Coax
Coax
Coax
Coax
9-pin D
Coax
25-pin D
25-pin D
4.1.3 IF Uplink/Downlink
Refer to Figure 4-1 for a block diagram of the IF switch.
The IF coaxial connectors are located on the IFU at the top of the DSU chassis. Each
switch channel has a dedicated uplink and downlink port that provides total
independence of link assignments.
Depending on the configuration, IF signals can be split and combined with minimum loss
prior to connection to the switch
(Combiners and splitters are not provided with the switch. Customers may wish to
purchase the Comtech EFData ICS-75 combiner/splitter, to fulfill this need.)