1.0 General Description

The Model 271 Auto Powered Fiber Optic Line Driver provides full duplex, asynchronous communication over two fibers. The Model 271 will allow for communication over two fibers. The Model 271 will allow for communication in harsh/hostile environments, has the benefit of immunity from EMI/RFI interference, and provides secure data transmissions.

2.0 Specifications

2.1 Interface:
Conforms to EIA RS-232C and CCITT, V.24 specifications. Pins 2 and 3, Transmit and Receive Data, switch selectable. Pin 4 internally connected to Pin 5. Pins 6, 8, and 20 internally connected. Pin 7 Signal Ground.

2.2 Connections:

2.2.1:

2.2.2 Fiber Optic: 271XST ST Connector

2.3 Data Rate: 300 to 56 KBPS

2.4 Operating Distance:

2.5 Wave Length: 850 NM

2.6 Power Budget: With 62/125 micron fiber 12db

2.7 Power: Power derived from RS-232 interface

2.8 Size: 2.5" L x 2" W x .875" H

2.9 Environment: 0° to 50° C, 5 to 95% RH

3.0 Installation

3.1 Digital Interface
The digital interface for the Model 271M is a male DB-25 while 271F is a female DB-25.

3.2 Fiber Interface
The fiber interface is an ST connector.

4.0 Operation

The Model 271 comes equipped with a switch that allows the reversing of Pins 2 and 3 of the RS-232 connector. When the switch is in the DTE position, Pin 2 of the RS-232 connector is an output (transmit to host device) and Pin 3 is an input. When the switch is reversed, Pin 2 becomes an input and Pin 3 becomes an output. When interfacing to a terminal or PC then the switch should be in the DCE position.

5.0 Troubleshooting

Operation can be verified if one of the devices to which the modems are attached is capable of operating in a full duplex mode, such as terminal. Connect the 271 to the terminal and using a short piece of fiber with two ST connectors connect the transmitter back to the receiver if the modem is functioning, then any data entered on the keyboard should appear on the screen.

6.0 Connector Pin Assignments

6.1 Power Connector

* These signals can be reversed using the selector switch.
** Connected together.
*** Connected together.

7.0 Power

The Model 271 can be powered in one of two ways:

The first is that it derives positive power from Pins 4, 5, 6, 8, or 20 (if available) and negative power from the data input pin (must be at least -5.0V in its quiescent state with the 271 attached.)

The second is that if the device that the 271 is connected to does not support any control signals, all power is then derived from the data input signal (must be at least -5.0V in the quiescent state and with the 271 attached.)

8.0 Assistance

If any assistance is required call Bomara Associates at (800)-5BOMARA or (978)-452-2299.
Technical Support E-Mail: bobr@bomara.com
or use our Online Contact Form

Document No. 0315-0087
Rev. A

Warranty

Telebyte warrants the equipment to be free from defects in material and workmanship, under normal and proper use and in its unmodified condition, for 12 months, starting on the date it is delivered for use. TELEBYTE's sole obligation under this warranty shall be to furnish parts and labor for the repair or replacement of products found by TELEBYTE to be defective in material or workmanship during the warranty period. Warranty repairs will be performed at the point of manufacture. Equipment approved for return for warranty service shall be returned F.O.B. TELEBYTE factory and will be redelivered by TELEBYTE freight prepaid, except for non- continental U.S.A. locations. These deliveries will be sent COD freight and import/export charges.

THE ABOVE WARRANTY IS IN LIEU OF ALL OTHER WARRANTIES, EXPRESSED OR IMPLIED, STATUTORY OR OTHERWISE, INCLUDING ANY IMPLIED WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. TELEBYTE SHALL NOT BE LIABLE FOR ANY DAMAGES SUSTAINED BY RESELLER OR ANY OTHER PARTY ARISING FROM OR RELATING TO ANY EQUIPMENT FAILURE, INCLUDING, BUT NOT LIMITED TO CONSEQUENTIAL DAMAGES NOR SHALL TELEBYTE HAVE ANY LIABILITY FOR DELAYS IN REPLACEMENT OR REPAIR OF EQUIPMENT.

Out of warranty equipment may be returned to the Greenlawn, NY customer service facility prepaid as described above. Return shipping charges will be billed to the customer. The repaired unit will have a 90 day warranty. In those cases where "NO TROUBLE" is found, a reduced charge will be billed to cover handling, testing and packaging.