American Fibertek MRX-8485C User Manual

© Copyright 2005, American Fibertek, Inc. 1027JD

Four Channel Video Multiplexer

Instruction Manual

with Bi-directional Data

MTX-8485C

MRX-8485C

Table of Contents

Functional Description ........................................................................3

Installation...........................................................................................3

Power Source .....................................................................................4

Power Connection...............................................................................4

Input / Output Connections .................................................................4

Typical System Data Connections .....................................................5

Data Configuration Switches...............................................................6

MTX-8485C Status LED Indicators.....................................................8

MRX-8485C Status LED Indicators.....................................................9

Data Termination Requirements.......................................................10

Offset Bias - RS485 Data Signals.....................................................11

Warranty and Service Information ....................................................12

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INSTALLATION AND OPERATION INSTRUCTIONS

INTRODUCTION

Thank you for purchasing your American Fibertek Series 8485C multimode four channel video
multiplexer with bi-directional data. Please take a few minutes to read these installation
instructions in order to obtain the maximum performance from this product.

FUNCTIONAL DESCRIPTION

The 8485C Series units operate as a transmitter / receiver pair for the transmission of four
simultaneous, real time baseband NTSC/PAL video signals with field configurable bi-directional
data over a single multimode fiber optic cable.

This link can accommodate either a single RS485 interface (2 or 4 wire) or both a RS422 and
RS232 interface. When used in RS422/RS232 mode, each interface functions independent of
the other. These units are factory shipped configured in the RS485 (4 wire) configuration.

The MTX-8485C transmitter accepts four video inputs and multiplexes these signals along with
the data signals onto a single optical output port for connection to the fiber transmission system.
Correspondingly, the MRX-8485C receiver converts the optical signal to four independent video
output signals along with the data signals.

The 8485C Series units operate on 50 um or 62.5 um multimode fiber. Refer to the data sheets
for detailed performance specifications.

The individual units may be configured for rack mounting or wall mounting depending upon the
position of the included mounting hardware.

INSTALLATION

THIS INSTALLATION SHOULD BE MADE BY A QUALIFIED SERVICE PERSON AND
SHOULD CONFORM TO THE NATIONAL ELECTRICAL CODE, ANSI/NFPA 70 AND LOCAL
CODES.

To install the MTX-8485C or MRX-8485C it is first necessary to mount the rack flanges to the
unit.

For rack mounting the ears are installed on the
sides of the unit with the surfaces that have
oval holes flush with the front of the unit as in
Figure 1. Mount the ears with the #10 flathead
screws provided. To mount in the rack cabinet,
use mounting screws that are appropriate for
the rack cabinet being used.

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For mounting the unit flush to a wall or other rigid
surface, the ears may be installed on the sides with
the oval holes flush with the bottom of the unit as in
Figure 2. Mount the ears with the #10 flathead
screws provided. Mount the unit to a rigid surface
using #10 (5mm) screws.

POWER SOURCE

The internal power supply accepts universal line voltage. Any mains supply from 100 to 240
VAC, 50 to 60 Hz may be used without modification or adjustment. A universal power connector
is provided on the rear of the unit to facilitate connection to the power mains.

POWER CONNECTION

The unit is supplied (in the US and UK only) with a three conductor power cord. The “ground”
conductor is directly connected to the chassis.

INPUT / OUTPUT CONNECTIONS

The fiber optic connection is made via a ST connector located at the back of the unit. Be sure to
allow sufficient room for the required minimum bend radius of the fiber cable used.

Video input and output connections are located on the rear of the unit. A BNC connector is
provided for each channel. Please note that channels five through eight are not used in this unit.
The video inputs are connected to an appropriate 75Ω baseband source such as a camera or a
video recorder output. The 75Ω video outputs can be looped through typical baseband video
inputs of switchers, recorders and other equipment as required. For proper operation, the
outputs must be terminated with 75Ω. For optimum performance the video cables should be the
shortest length of coax practical.

Data input and output connections are located on the rear panel terminal block. A mating plug
connector is provided. The figure below identifies the specific connections for the RS485 data
connections. See next page for RS422 / RS232 data connections.

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