beautypg.com

Comtech EF Data SNM-1000 User Manual

Page 27

background image

SNM-1000 Node Control Modem

Revision 3

Introduction

MN/SNM1000.IOM

1-7

Table 1-1. General Specifications (Continued)

Demodulator
Input Power:

Desired Carrier
Maximum Composite


-30 to –55 dBm
-5 dBm or +40 dBc

Input Impedance

75

Ω (Optional: 50Ω)

Input Return Loss

> 20 dB

Carrier Acquisition Range

± 35 kHz from 100 Hz to 35 kHz, in 1 Hz steps

Acquisition Time: 19.2 bps, R=1/2

< 2 seconds

Sweep Reacquisition

0 to 999 seconds, in 1 second steps

Data Clock

Internal, External, Transmit, Recovered RX

Outbound (from NMS)

Continuous transmission, Time Division Multiplex
(TDM), 19.2 kbps, QPSK, R=1/2

Inbound (to NMS)

Burst transmission, (TDMA) Slotted Aloha,
19.2 kbps, QPSK, R=1/2

Processor
M&C Processor

Single processor for node control EEPROM variable
storage Memory life without power for 10 years.

User Port Interface
Interface Type

EIA-232

Data Rate

19.2 kbps

Data Bits

8

Parity

None

Stop Bits

1

Application

Remote circuit initiation and termination via command
interface; Transmits and receives service terminal
messages.

Control Interface
EFBUS1:
Interface Type

EIA-485

Data Rate

9.6 or 19.2 kbps

Application

Multi-drop bus used to control external data traffic
modems

Compatibility

Standard Comtech EF Data remote commands

Modems Supported
(Not limited to-)

SDM-100, SDM-300/300A, SDM-2020M/D,
SDM-6000, SDM-8000, SDM-9000, CDM-550/550T,
CDM-600, CiM-550