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IDM NTD421 (CS) Magnet Telephone Optical Terminal

IDM NTD421

IDM NTD421

Telephone Optical Terminal·📅UpdatedMay 12, 2026·✍️管理员

Provides 2 telephone lines + 2 groups of physically isolated 100M Ethernet ports, among which ports 1, 2, 3 and the fourth port are physically isolated, with 220V power supply. Dual physically isolated wire-speed 100M Ethernet channels; the 3 shared 100M Ethernet ports can also be divided into VLANs for isolation. The voice interfaces can be FXO central office automatic telephones, FXS remote automatic telephones, or MAG magnet telephones, and provide 2 RS485 interfaces. It can form chain network and ring network applications, with dual optical ports for cascading. The 8-position DIP switch on the panel is used to set the station address in the chain network. Provides a standard SNMP network management interface.

Magnet telephone optical terminalChain network magnet telephone optical terminalRing network magnet telephone optical terminal

I. Overview

The IDM NTD421 (CS) Magneto Telephone Optical Terminal is a new generation optical-electrical integrated transmission device launched by Beijing Ruiguang Jiyuan Digital Technology Co., Ltd., based on high-speed optical fiber transmission technology and PCM technology. It integrates Ethernet transmission and PCM multi-service access functions, meeting the demands of users for fiber transmission and access of various broadband and narrowband services. The IDM NTD421 (CS) Magneto Telephone Optical Terminal can directly connect remote telephones, computers, cameras, and other terminals; when paired with the corresponding G3CP boards, it can support point-to-point, chain network, ring network, and other network topologies. The optical terminal can be widely applied in private networks such as public security, electric power, railway, and mining, as well as public network fields including Mobile, Unicom, and Telecom.

II. Product Features

II. Product Features
The optical terminal adopts a desktop chassis structure design with high integration and compact size;
Integrates high-speed optical fiber transmission, PCM service access, and Ethernet access technologies into the device;
Supports 2 channels of 250Mbps optical transmission interfaces with FC optical module interface format, capable of forming chain network, ring network, or point-to-point optical port mutual backup networking;
4 Ethernet interfaces; in point-to-point mode, every two share 1 physically isolated wire-speed 100M Ethernet; in chain networking mode, the 4 Ethernet ports share one group of wire-speed 100M Ethernet;
The optical terminal provides two magneto telephone channels (MAG);
The optical terminal provides two half-duplex RS485 interfaces, or one full-duplex RS422 interface;
Can form point-to-point, chain network, and other network topologies; the standard model has a non-repeater transmission distance of 40 kilometers; distances beyond this can be customized;
DC5V power supply.

III. Technical Specifications

1) Optical Interface

Interface Type
FC
Fiber Mode
Single-mode (Multi-mode optional)
TX/RX Rate
250M/250M
TX/RX Wavelength
1310nm/1550nm
Optical Output Power
-12~-6dBm
Receiver Sensitivity
Better than-18dBm
Transmission Distance
20Km, with optional long-distance optical modules available for extended fiber transmission over greater distances

2) Ethernet

Interface Type
RJ-45
Transmission Rate
10M/100M/1000M auto-negotiation
Standard Protocol
Supports IEEE802.3
Operating Mode
Full/half-duplex/auto-negotiation

3) FXO, FXS Interfaces

Audio Range
300Hz~3400Hz
Compression
A-law per ITU G.711
Impedance
Three-element complex impedance 200Ω+560Ω//0.1μF
Loop Current
20mA/channel

4) Power Supply and Power Consumption

Power Supply
AC220V/DC-48V
Power Consumption
≤90W

5) Environmental Conditions

Operating Temperature
-10oC ~+50oC
Relative Humidity
0~95% (non-condensing)

6) Product Dimensions

Length×Depth×Height
××(mm)

IDM NTD421 (CS) Optical Terminal Front Panel and Rear Panel NTD421 Rear View

IDM NTD421 (CS) Optical Multiplexer Front Panel IDM NTD421 (CS) Optical Multiplexer Rear Panel

FAQs

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Device cannot be powered on Check whether the power cable is connected correctly.

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