Description (with rs-301 option), 2 description (with rs-301 option) – Comtech EF Data SMS-301 User Manual

Page 17

SMS-301 Redundancy Switch

Introduction

Rev. 3

1–3

1.1.2

Description (With RS-301 Option)

The 1:1 switch, when used with the RS-301 Remote Switch, is a fully-automated
protection switch designed for use with the Comtech EFData SDM-300/-300A Satellite
Modem that are equipped with the 8-Channel MUX option. It provides redundancy for
the one prime modem using identical backup satellite modem. The 1:1 switch provides
common interfaces for the RF uplink and downlink equipment. The integrated uplink 1:1
switch and downlink splitter operate at IF frequencies in the range of 50 to 180 MHz.

The RS-301 Remote Switch is a separate 19-inch (48.3 cm) rack-mounted chassis. It is
controlled by the 1:1 switch, and provides redundancy for the data interface between the
primary modem, backup modem, and customer equipment. The front panel provides
convenient access to eight tributary data channels (EIA-232 and EIA-422 clock and data)
and one auxiliary data channel. Figure 1-3 illustrates the system block diagram.

Note: The default connections are to Modem A.

1 F O R 1 S W IT C H

M O D E M R E M O T E
E IA -4 8 5

S TAT U S FA U LT S

S D M -3 0 0 / 3 0 0 A

M O D E M A

T R A N S M IT IF

R E C E IV E IF

B A S E B A N D D ATA

T X /R X

S D M -3 0 0 / 3 0 0 A

M O D E M B

T R A N S M IT IF

J1 0

J1 5

R S -3 0 1

R E M O T E

S W IT C H

J1 3

J1 4

E IA -2 3 2 O R E IA -4 8 5

H O S T T E R M IN A L

O R C O M P U T E R

M O D E M B D ATA (8 T R IB & 1 A U X )

B A S E B A N D D ATA

T X /R X

S W IT C H

M & C

L O G IC

S W IT C H

C O N T R O L

T R A N S M IT IF

5 0 T O 1 8 0 M H z T O

U P C O N V E R T E R

J1 6

J1 4

M O D E M A D ATA (8 T R IB & A U X )

J1 T R IB 1 D ATA

J2 T R IB 2 D ATA

J3 T R IB 3 D ATA

J4 T R IB 4 D ATA

J5 T R IB 5 D ATA

J6 T R IB 6 D ATA

J7 T R IB 7 D ATA

J8 T R IB 8 D ATA

J9 A U X D ATA

R E M O T E

C O N T R O L

N O T E : J7, J8 , A N D J9
A R E N O T U S E D .

S P L IT T E R

C O N T R O L

B U S

E X T E N D E R

C A R D

Figure 1-3. System Block Diagram (With RS-301 Option)