Comtech EF Data SMS-301 User manual

Modem
A
ccessories
SMS-301 Modem
Protection Switch
2114 West 7th Street, Tempe,Arizona 85281 USA Voice 1 480 333 2200 Fax [phone] Email [e-mail]
Comtech EF Data reserves the right to change specifications of products described in this document at any time withoutnotice and withoutobligation to notify any person of such changes. Information in this
document may differ from that published in other Comtech EF Data documents. Referto the website or contact Customer Service for the latest releasedproduct information.
© 2007 Comtech EF Data Part Number ds-sms301.doc 3/21/2006
FEATURES
• Full feature monitor and control processor
• Remote input for configuration and status
• 1:1 configuration
• One rack unit (1RU) chassis
APPLICATIONS
The SMS-301 is a fully programmable 1:1 protection
switch providing complete redundancy for one prime and
one backup modem. The SMS-301 switch is designed to
operate with Comtech EF Data satellite modems and is
a direct replacement for the SMS-651B 70/140 MHz
Switch.
Programming the SMS-301 is accomplished through the
front panel keyboard or the remote interface. Complete
functionality control and monitoring of switch status and
faults are easily accessed through the remote port
connection.
The SMS-301 simultaneously switches data and IF
paths, either independently or dependently. The
switching type is selectable through the front panel or
remote port, eliminating the need for firmware changes
and allowing maximum in-use flexibility.
When a fault is detected in the online modulator or
demodulator, a switch to the offline modem occurs if the
backup is not in a faulted condition. The transmit data is
sent to the backup modem by the 1:1 switch to prevent
false indications of transmit faults. The actual switching
can be accomplished in under 20 milliseconds, with
programmable modulator and demodulator switching
delays in the range of 0 to 127 seconds.
The front panel LEDs indicate which modulator and
demodulator (prime or backup) are online. The LEDs
also indicate the following:
• Active faults in the modulator or demodulator
• Status of the SMS-301’s redundant power supplies
• Mode of the switch (automatic or manual)
OTHER FEATURES
• Uses standard Comtech EF Data modem as backup
or prime
• Dependent or independent modulator and
demodulator switching
• Local/remote, automatic/manual control
• Redundant power supplies and AC inputs
• Easy installation
SIGNALS MONITORED
• Operation mode: Automatic or manual
• Switching mode: Independent or dependent
mod/demod
• Modulator/Demodulator online delay
• Modem online: A or B (dependent mode)
• Modulator/Demodulator online: A or B (independent
mode)
• Remote configuration (local only): EIA-232 or EIA-
485, address, baud, parity, bits per word
• Remote mode (switch)
• Clear stored faults
• Current faults
• Stored faults
• Switch status
• Equipment type
• Store/recall multiple switch configurations
• Remote access to modulator/demodulator status
• Modem configuration copy to opposite modem

Optimizing Satellite Communications
www.comtechefdata.co
m
SMS-301 Modem Protection Switch
SPECIFICATIONS
System
Data Interface EIA-232, V.35, EIA-422, G.703, and MIL-STD-188-114
Data Rate 20 Mbps max.
IF Interface impedance 75ΩBNC (50 Ωoptional)
IF Frequency 50 to 180 MHz
Operation Modes Auto/manual, local/remote
Power 90 to 264 VAC, 47 to 63 Hz, 30W max.
Size 19 inch W x 15.2 inchD x 1.75 inch H (1RU) (48.2 x 38.6 x 4.4 cm)
Weight 9 lbs. (4.0 kg) max.
Controls
Switch Remote/local
Modulator A/B online select or auto
Demodulator A/B online select or auto
Indicators
Power Supplies 1, 2 on
Mode Automatic or manual
Modulator A/B online
Demodulator A/B online
Faults Transmit, receive, system, and stored
M&C
Remote Monitor and Control 9-pin D sub connector, EIA-232 or EIA-485 (2- or 4-wire), front panel selectable
Monitor and Control
Serial Interface EIA-232 or EIA-485, programmable
Baud Rate 150 to 19200 bit/s, programmable
Parameters Controlled Start/stop, parity, data bits
SMS-301 BLOCK DIAGRAM
SWITCH M&C
LOGIC
MODEM A
MODEM B
TRANSMIT IF
TRANSMIT IF
RECEIVE IF
RECEIVE IF
BASEBAND DATA
TX/RX
BASEBAND DATA
TX/RX
MODEM REMOTE
EIA-485
J13
J14 STATUS/FAULTS
REMOTE
CONTROL
J3 J6 J7
J10
J4
J8
J1
J9J5J2
SPLITTER
BASEBAND DATA I/O
TO/FROM CUSTOMER
RECEIVE IF
50 TO 180 MHZ
FROM
DOWN CONVERTER
TRANSMIT IF
50 TO 180 MHZ
TO UP CONVERTER
EIA-232 OR EIA-485
HOST TERMINAL
OR COMPUTER
1:1SWITCH