Comtech EF Data SMS-301 - Manual (Page 69)

SMS-301 Redundancy Switch Theory of Operation
Rev. 3 4-3
4.2 SMS-301 Data Interface
4.2.1 IBS, IDR, ASYNC, or D&I (J1, J2, J3), 50-Pin (PL/5951)
The applications for this board are IDR, IBS, ASYNC, or D&I format data. The board
consists of three 50-pin data I/O connectors, interface, and switching electronics. There
are no configuration jumpers on the 50-pin board.
The interface to the M&C motherboard is via a 40-pin connector located along one side of
the board. The board, under M&C control, will switch data between the prime modem
(J2), and/or the backup modem (J3), and the common customer-data interface (J1).
The M&C automatically detects the type of board installed and presents this information,
via the front panel display, under Interface Type in the Utility System menu.
4.2.2 EIA-422/-449, G.703, or V.35 (J1, J2, J3), 37-Pin (PL/5952)
The applications for this board are EIA-422/-449, G.703 or V.35 format data. The board
consists of three 37-pin data I/O connectors, interface, and switching electronics.
The interface to the M&C motherboard is via a 40-pin connector located along one side of
the board. The board, under M&C control, will switch data between the prime modem
(J2), and/or the backup modem (J3), and the common customer-data interface (J1).
The M&C automatically detects the type of switch board installed and presents this
information, via the front panel display, under Interface Type in the Utility System menu.
4.2.3 LVDS-DVB TX, (J1, J2, J3), 37-Pin, (PL/6201-1)
There are no configuration jumpers on the LVDS board. The current version of this board
is for the SDM-2020 Satellite Modulator only. The intended signal flow path is from the
customer-connection on J1 to the switched equipment on J2 and J3.
In the powered down state, this board provides an unbuffered signal path from J1 to J2.
When power is available to the board, the signals from J1 to J2 and J3 are buffered.