Optical Equipment

1E1 Fast Optical Fiber Modem

Fast Optical Fiber Modem

The FHC-4030 is designed to provide fiber connection for E1 equipment. It includes a E1 Line Interface Unit that provides E1 line driver/receiver, data/clock recovery, jitter attenuation, AMI/B8ZS/HDB3 encoding, AIS (Alarm Indication Signal) detection, BPV (Bi-Polar Violation) detection, and loop back mode. It offers two modes of Loopback for testing the connection integrity. In the Local Loopback mode, the modem loops back the received E1signal. In the Remote Loopback mode, the modem sends loopback codes to cause the far-end modem to loop back the received optical data.

Product Datasheet
Resources (firmware, documents etc...)


  • E1 G.703 Interface
  • E1 Signal Jitter/Wander Attenuation
  • E1 AMI/HDB3 Codes
  • Local Loopback and Remote Loopback
  • Automatic Alarm Signaling on both Line and Fiber
  • 18 dB Typical Optical Link Margin
  • Multiple Link status Indicators


Product Specification:

  • Electrical Interface: E1 G.703 Interface
  • Data Rate: 2.048 Mbps 50 ppm
  • Impedance: 75 Ohm balanced & 120 Ohm balanced
  • Connector: BNC-female, unbalanced & DB-15 female, balanced
  • Line Code: AMI/B8ZS


  • Wave Length: 802 nm/1300 nm multimode & 1300 nm single mode
  • Link Margin: 18dBm (min.) multimode @ 62.5mm & 15dBm (min.) single mode @ 9mm
  • Connector: ST/FC


  • DSX-1 Cable Length: 5 different impedance selections to match DSX-1 cable at length from 0 to 655 feet
  • E1 Line Coding Format: AMI/HDB3 for VLM-100E1
  • Local Loop Back: Enabling Local Loopback Mode
  • Remote Loop Back: Enabling Remote Loopback Mode
  • T1/E1 Line AIS: Enabling the alarm signal to E1 line
  • Fiber Link AIS: Enabling the Alarm Signal to the Fiber


  • Power Supply: 9 to 12 VDC @ 300 mA
  • Operating Temperature: 0°C - 60°C
  • Storage Temperature: -10°C - 85°C
  • Humidity: -5% to 95% no condense
  • Dimensions: 8.9(L)in x 6.5(W)in x 1.6(H)in