Extend Legacy 9.6Kbps Circuits Over Fiber – Line Powered

Fiber Optic Isolation Systems - 4 Wire 9.6 Kbps DDS
CO Card

RLH 9.6k fiber link cards are designed to process incoming bipolar signals (3.2V P-P Max) with a digital data signal rates from 4.8 to 9.6Kbps. It also supports analog data with a bandwidth of 50 kHz to 500 Hz at a maximum of 9.6Kbps. An electrical copper signal is converted into an optical signal and transmitted over 2 strands of fiber optic cable.

The CO Card will operate from a 24~54VDC at a minimum of 18mA sealing current on the send and receive Telco pairs. The CO Card can also be local powered by an isolated power source (24-54VDC).

The SUB Card is typically powered by a 24~54VDC, 18mA local power source. It may also be powered by simplexed current on the send and receive pairs from the subscriber equipment.

This fiber link card is designed to be installed into any of the RLH Fiber Link Card Housings, and occupies a single card slot.


  • Supports 4 Wire 9.6 Kbps DDS
  • 500 Hz to 50 kHz bandwidth
  • 2.4 Kbps to 9.6 Kbps data rate
  • Environmentally hardened, superior operating temperature range
  • Available in Single or Multimode
  • Dual power capable, line or 24-56VDC local power
  • Available with ST or SC Connectors
  • Compatible with a wide variety of Card Housings
  • Limited Lifetime Warranty
  • Made in USA

Transmission Method:
Frequency modulated light via two optical fibers

Multimode: 850nm
Singlemode: 1310nm

Fiber Type/Distance:
Multimode (62.5/125µm, 50/125µm): 1.5 miles/2.5km
Singlemode (9/125µm): 9 miles/15km; Long Haul 37 miles/60km

Fiber Connector Type:
ST or SC

7in. x 4in. x 1in. (177.8mm x 101.6mm x 25.4mm)
(Standard RLH Fiber Link Card Form Factor)

Operating Temperature:
-40˚F to +158˚F (-40˚C to +70˚C)

Operating Humidity:
95% non-condensing

General Information Specialized Drawings Miscellaneous
4 Wire 9.6 Kbps DDS System
4 Wire 9.6 Kbps DDS System

For product questions, volume pricing and/or delivery outside of the US and Canada, please contact sales.


Please contact us to get a quote for your project.

*Lead times are estimates and may vary. You will be contacted within 1 business day to go over the details of your order. If you require a specific date, let us know!
*Days = Business Days

WarningWarning: This product can expose you to chemicals including arsenic, which is known to the State of California to cause cancer. For more information, go to www.P65Warnings.ca.gov.

RLH Industries - Fiber Optic Link
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