Redback A 1741 - User Manual

Operating Manual
A 1741 Message Player
The A 1741 is an MP3 based message player and tone generator designed for public address, security, customer direction
or emergency evacuation announcements.
1.0 Installation
Power requirements: The A 1741 needs a minimum of 12VDC at 300mA to work correctly. Maximum working voltage is
30VDC, do not exceed 30VDC as it will cause permanent damage to the unit. A good working voltage is between 12 and
24VDC. The power is connected via the 2.1mm (tip positive) DC socket on the rear of the unit (see g 1).
Output: Output is via the stereo RCA connectors on the rear. Output level is nominal 500mV but is related to the recorded
level of the MP3.
Input triggers: The input triggers are activated by closing contacts on the rear of the unit whether by a normally open
switch or a timer or controller. (Note: These triggers have a common ground).
Trigger Switches: The messages can also be activated by pressing the switches on the front of the unit. Note: The Alert
and Evac buttons must be held down for 3 seconds before they activate. This reduces the chance of accidental triggering.
Switched output: The switched output terminal is triggered when any zone is activated. The voltage is the same as the
power supplied to the unit. ie if the A 1741 is powered by 12V, the switched output voltage will be 12V.
2.0 Play modes
Alternate: When the A 1741 is in Alternate mode (DIP1 switch1 OFF) (see Fig 3) the closing contact must be held for the
duration of the MP3 play time, if it is released before the MP3 ends the MP3 will stop playing immediately. If the contact is
held closed continually the MP3 will continue to loop over and over until the contact is released.
Momentary: In Momentary mode (DIP1 switch1 ON) (see Fig 3) a momentary closing contact or pulse on the trigger pins
will activate the MP3. The A 1741 will continue to play the MP3 till it nishes and will stop playing and wait for another
trigger activation.
To stop an MP3 playing when in Momentary mode the Cancel trigger or Cancel switch is used. A momentary closing
contact on the Cancel trigger or closure of the Cancel switch will stop the MP3 playing (it is recommended that the Cancel
contact or switch be held up to 2 seconds to ensure the MP3 stops playing)
User manual revision number 1.3 26/05/2015

Summary

DIP Switch Settings

DIP SW 1: Momentary or Alternate Triggering

Configures trigger action: hold for duration (Alternate) or pulse (Momentary). Affects MP3 playback.

DIP SW 2: Alert;Evacuation Tones ON or OFF

Enables or disables Alert/Evac tones from front switches and rear contacts.

DIP SW 3: Front Switch Activation

Disables front panel switches (including Cancel, Alert, Evac) when set to OFF.

DIP SW 5-8: Alert;Evacuation Tone Change Over

Sets delay (30-450s) for switching from Alert to Evacuation tone, or disables changeover.

MP3 Loading Procedure

SD Card Preparation

Copy MP3 to Trigger Folder

Connect SD card to PC, copy MP3 file into 'trig1' folder, ensure correct naming and attributes.

Emergency Tones

Alert Tone Functionality

Activated by contact or button. Can switch to Evacuation tone after a set time via DIP switches.

Evacuation Tone Functionality

Activated by contact or button. Can be set to repeat twice every three cycles.

Priority of Emergency Tones

Emergency tones override other triggers (1-8). Evacuation has priority over Alert.

Troubleshooting and Specifications

Troubleshooting No Power

Check power supply jack size (2.1mm), voltage (12-30VDC), and output type (DC, not AC).

Troubleshooting Message Active LEDs

Indicates SD card issue: not inserted correctly or not formatted. Check folders.

Troubleshooting Emergency Tones

Ensure DIP switch 2 is ON to activate emergency tones.

Power Supply Specifications

Output Specifications

MP3 Specifications

Redback A 1741 Specifications

Power

power supply voltage	12-30 VDC
idle current draw	150 mA
maximum current draw	300 mA

Audio Output

output type	Stereo RCA
output voltage	500 mV nominal
channels	Stereo or mono

Storage

SD card size	256 MB to 16 GB
MP3 length on 8GB card	800 mins @ 128 kbps, 44 kHz
bit rate	128 kbps recommended