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4

The video output connection is made via a BNC connector on the right side of the unit. 
The 75

 video output can be looped through typical baseband video inputs of switchers, 

recorders and other equipment as required. For proper operation, the output must be 
terminated with 75

. For optimum performance the video cables should be the shortest 

length of coax practical. 

 

Data input and output connections are made via a terminal block on the right side of the 
unit. Follow label on unit and customer connection drawing for proper orientation of 
RS485 data input and output. Please note that RS485 two wire applications utilize the 
four wire data out (+) and data out (-) terminals.  

 
DATA CONFIGURATION 

The MRM-1485 is shipped from the factory in the RS485 4-wire configuration. In 
order to configure the unit for RS485 two wire operation, the unit needs to be 
opened up and several switch settings and jumper pins need to be modified using 
the internal switch/jumper settings shown on the next page.  
 
The MRM-1485 is shipped from the factory with internal data input and output 120 
ohm terminations switched on. In order to remove the internal terminations, the 
unit needs to be opened up and several switch settings need to be modified using 
the internal switch/jumper settings shown on the next page.  

 
See page 7 for an explanation of termination and offset bias requirements for RS485 
data. To open the MRM-1485, remove the screw on the bottom of the module. Also 
remove two screws holding the end panel to the chassis on the side with the video and 
data connections. Slide PCB assembly out of chassis to access the switch and jumper 
locations. 

Содержание MRM-1485

Страница 1: ... Copyright 2003 American Fibertek Inc 0731JD Instruction Manual MRM 1485 Video Receiver With Bi directional RS485 ...

Страница 2: ...on 3 Installation 3 Power Source 3 Power Connection 3 Input Output Connections 4 Data Configuration 4 Switch Jumper Settings 5 MRM 1485 Status LED Indicators 6 RS 485 Termination and Offset Bias Requirements 7 Warranty 8 Service Information 8 ...

Страница 3: ...er to the data sheets for detailed performance specifications This unit is contained in a compact and rugged aluminum housing with internal dc voltage regulation The detachable terminal block and LED indicators provide for easy installation and monitoring of video data and dc power The MRM 1485 is designed for mounting as a modular stand alone unit For a rack mounted version please see the RRM 148...

Страница 4: ... from the factory in the RS485 4 wire configuration In order to configure the unit for RS485 two wire operation the unit needs to be opened up and several switch settings and jumper pins need to be modified using the internal switch jumper settings shown on the next page The MRM 1485 is shipped from the factory with internal data input and output 120 ohm terminations switched on In order to remove...

Страница 5: ...5 ...

Страница 6: ...e RS485 input data from the electrical interface through the MRM 1485 and out onto the fiber The intensity of this indicator will vary with input data patterns however in typical applications it will cycle on and off as data is transmitted RS485 status associated with this LED is summarized below DATA TX LED RS485 Status Red Data Flow Present Off Data Flow Not Detected DATA RX A red LED indicator ...

Страница 7: ...s at the furthest electrical devices at the ends of the wire pair For instance if several RS485 devices are connected in a daisy chain fashion the wire connection would loop across all devices in a chain The furthest two points in the chain would need to be terminated A termination resistor for RS485 input data can be selected in the MRM 1485 using switch 1 A termination resistor for RS485 output ...

Страница 8: ...R THE FOREGOING WARRANTY THERE IS NO WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE OR OTHERWISE EXPRESSED OR IMPLIED WHICH EXTENDS BEYOND THE WARRANTY SET FORTH IN THIS AGREEMENT In any event American Fibertek will not be responsible or liable for contingent consequential or incidental damages No agreement or understanding expressed or implied except as set forth in this warranty...

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