3M MODULE A125 user manual

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Noise Reduction Module
Model A125

Installation Instructions



Description

The 3M A125 Noise Reduction board (3M part number 78-9236-6453-2) improves the inbound intelligibility of an
intercom system by reducing environmental background noise from vehicles, airplanes, noisy intersections, wind,
etc.

System Requirements

The 3M A125 Noise Reduction Module requires a 3M model C921BA or C922AA Base Station.

Installing the Noise Reduction board into the 3M Base Station
1. Re

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***Important installation notice*** Starting with serial number 125002477, the A125 Noise Reduction Module, Internal has a wider ribbon cable plug. A limited number of these Noise Reduction Modules have two individual ribbon cable plugs. The wider ribbon cable plug(s) are too wide to fit into the blue 20-pin base station receptacle. The receptacle on the wireless base station board must be trimmed and the ends opened. Use a sharp razor knife and make four vertical cuts. Fold the ends o

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System Configuration The A125 Noise Reduction board is configured by two jumper switches, (JMP1 and JMP2), shown in Table 1. Jumper Position A Position B Position JMP1 * Separate microphone & OSM (speaker used as both a speaker at menu sign/post speaker and a microphone at the menu sign/post) JMP2 * C960 Intercom C5000 Intercom Note: * Indicates factory default settings Table 1. A125 Jumper Settings Mode Configuration The A125 Noise Reduction board can be configure

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Status Indication The condition of the red LED on the 3M C960 base station indicates the current status of the unit. The LED can be off, blink at defined intervals, or be constantly lit. Table 3 illustrates the status indicated by the LEDs. Status LED Power OFF LED Off Normal Mode LED blinks once per every two seconds Test Mode LED blinks three times per second Fault Condition LED is solid red (constantly lit) Table 3. A125 Status Indication Final Checkout Procedure 1. On t