Extend Analog Phone Lines Over Fiber With Caller ID – Line Powered​​

Fiber Optic Isolation Systems - 2 Wire POTS Enhanced
2 Wire POTS Enhanced

The 2 Wire POTS (Plain Old Telephone Service) Enhanced system provides transmission of standard analog POTS, telemetering, or PBX loop start signals over two optical fibers. The system transmits signals in the voice-frequency or audio range (300Hz-3400Hz) while providing ringing and off-hook detection, and supports caller ID and forward disconnect. Common applications include telephone, fax, and dial-up modems.

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

A complete system uses one CO and one Sub card.

Note: Square wave ringing option is available (SM10). Contact the factory for additional information.


  • Ideal for critical, high voltage, remote or un-manned locations that must remain operating 24/7/365
  • Enhanced FXO/CO cards are loop powered
  • Available in Single and Multimode, ST or SC Connectors
  • Provides ringing and off-hook detection
  • Supports Caller ID and Forward Disconnect
  • Convenient sub card LED status indicators
  • Standard RLH form factor compatible with wide variety of housings
  • Environmentally hardened to operate in -40°F to +158°F (-40°C to +70°C) environments
  • Limited Lifetime Warranty
  • Made in USA

Transmission Method:
Frequency modulated light via two optical fibers

Multimode: 850nm
Singlemode: 1310nm
SM Long Haul: 1310nm

Fiber Type/Distance:
Multimode (62.5/125µm, 50/125µm): 1.5 miles/2.5km
Singlemode (9/125µm): 20 miles/32km

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

2 Wire POTS Enhanced System
2 Wire POTS Enhanced System


Lead Time: 1 to 2 Weeks*

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


2 Wire POTS Enhanced

Product configurationCard TypeModeConnectorDistanceFibersPart numberPricehf:att:pa_card-typehf:att:pa_modehf:att:pa_connectorhf:att:pa_distance
Enhanced CO/FXO Card, Multimode, ST, 2.4km/1.5 miles, Dual FiberEnhanced CO/FXO CardMultimodeST2.4km/1.5 milesDual Fiber8806-1234-05$970.00
SUB/FXS Card, Multimode, ST, 2.4km/1.5 miles, Dual FiberSUB/FXS CardMultimodeST2.4km/1.5 milesDual Fiber8806-1244-05$950.00
Enhanced CO/FXO Card, Singlemode, ST, 32km/20 miles, Dual FiberEnhanced CO/FXO CardSinglemodeST32km/20 milesDual Fiber8806-1261-05-LH$1,330.00
SUB/FXS Card, Singlemode, ST, 32km/20 miles, Dual FiberSUB/FXS CardSinglemodeST32km/20 milesDual Fiber8806-1271-03-LH$1,310.00
Enhanced CO/FXO Card, Singlemode, SC, 32km/20 miles, Dual FiberEnhanced CO/FXO CardSinglemodeSC32km/20 milesDual Fiber8805-1261-05-LH$1,430.00
SUB/FXS Card, Singlemode, SC, 32km/20 miles, Dual FiberSUB/FXS CardSinglemodeSC32km/20 milesDual Fiber8805-1271-03-LH$1,410.00
  • For the square wave ringing option, please note your part number, add -SM10 to the end, and get your quote here
  • A complete system requires a FXO/CO card and a FXS/Sub Card
  • CO cards are Line Powered, SUB cards are 24~56VDC local powered

*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.

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