Redback A 1720c User manual

www.redbackaudio.com.au Redback® Proudly Made In Australia 1

Redback® A 1720C MP3 Tone Generator

User manual revision number: 1.0 29/11/2023

Operating Manual

The A 1720C 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 1720C needs a minimum of 12VDC at 300mA to work correctly (Note: a minimum of 24V

DC is needed if the switched output is required). Do not exceed the maximum working voltage of 30VDC, as it will cause

permanent damage to the unit. A good working voltage is between 12 and 24VDC. The power is connected via 2 way screw

terminal (see g 1).

Output: Stereo output is via screw terminals and RCA sockets. 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 whether by a normally open switch or a timer or

controller.

Switched output: The switched output terminal is triggered when any zone is activated. Note: A minimum of 24VDC must

be used to power the A 1720C for the switched output to operate. The voltage output from the switched output terminals

is the same as the power supplied to the unit.

Fig 1

4 5 67

Connections

1. Stereo audio output

2. Left & right RCA outputs

3. Switched power output

4. Trigger 1-8 inputs

5. Evac Trigger

6. Alert Trigger

7. Cancel Trigger

8. Micro SD Card slot

9. DIP switch

10. BCD switch

11. Power input (12- 30V)

www.redbackaudio.com.auRedback® Proudly Made In Australia2

Redback® A 1720C MP3 Tone Generator

2.0 Accessing Files On The Micro Sd Card

Remove power from the A 1720C and then remove the micro SD card from the unit.

To remove the micro SD card push the card in and it will eject itself.

The micro SD card will then need to be connected to a PC. You will need a PC equipped with a micro SD card reader to

do this (not supplied). If a Micro SD slot is not available then the Altronics D 0371C USB Memory Card Reader or similar

would be suitable (not supplied).

Make sure the PC is on and card reader connected and correctly installed. Then insert the micro SD card into the reader.

Go to “My Computer” or “This PC” and open the micro SD card which is usually marked “Removable disk”.

In this case it is named “Removable disk (K:)”. Click on the Removable disk and the contents of the micro SD card should

be listed as shown in gure 2.

Fig 2

Included on the micro SD card is a folder labelled #LIBRARY# (shown in gure 3) which includes a collection of sample

tones and messages which can be used for the trigger MP3’s.

Fig 3

2.1 Installing MP3 les into trigger folders

To open a trigger folder simply double click on the relevant folder, such as our example of the trig2 folder shown in gure

4. Inside the folder will be a default MP3 le, named in this case “trigger2.mp3”. This is the audio le that is played when

trigger 2 is activated. Delete this le and replace it with an MP3 le you want to play when you activate trigger2. This MP3

could be a le from the #library# folder or an MP3 of your own choosing.

The MP3 le name is not important only that there is a legitimate MP3 le in the trig2 folder (WAV, OGG or other formats

www.redbackaudio.com.au Redback® Proudly Made In Australia 3

Redback® A 1720C MP3 Tone Generator

do not work). Repeat this process for the required triggers.

Note: More than one MP3 le can be placed in the trigger folders. These will be played randomly while the trigger is acti-

vated.

Fig 4

2.2 MP3 le format

The audio les used must be in MP3 format, they cannot be WAV, OGG or other formats. The minimum recommended

MP3 format is 128kbps, 44.1kHz, 32bit, VBR or CBR, Stereo (even better as mono).

NOTE: the MP3 les used cannot be “Read only”. To check this, right click on the MP3 le and scroll down and select

Properties, you will get a popup window. Make sure the “Read Only” box has no tick in it.

2.3 Alert and Evac Messages

A message can be inserted every three alert cycles and/or every three evac cycles . A Voice message could be something

like “please evacuate the building”. To install an Alert or Evac message open the “voice” folder and then select the alert

or evac folder. Figure 5 illustrates the location of the voice/evac folder.

Delete the le in the folder and replace it with an MP3 message le you want to play when you activate the alert or evac.

This MP3 could be a le from the #library# folder or an MP3 of your own choosing.

Note: If an Alert or Evac message is not required delete the les in these folders.

Fig 5

3.0 Play modes

Alternate: When the A 1720C is in Alternate mode (DIP switch 1 OFF) (see Fig 1) a momentary closing contact or pulse

on the trigger pins will activate the associated trigger folder MP3. The A 1720C will continue to play the MP3 until it n-

ishes and will then stop playing. If the contact is held closed continually the MP3 will continue to loop over and over, or if

there are multiple MP3 les in the trigger folder, they will be played randomly until the contact is released.

www.redbackaudio.com.auRedback® Proudly Made In Australia4

Redback® A 1720C MP3 Tone Generator

To stop an MP3 playing when in Alternate mode the Cancel trigger is used. A momentary closing contact on the Cancel

trigger will stop the MP3 playing (It is recommended that the Cancel contact be held for up to 2 seconds to ensure the

MP3 stops playing).

Momentary: In momentary mode (DIP switch 1 ON) (see Fig 1) 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 still only play once and then stop. If there are multiple MP3 les in the trigger folder, a le will be

selected at random and played once.

4.0 Cancel Function

As outlined in the Alternate Playback mode, the cancel trigger can be used to cancel any activated trigger. The A 1720C

now includes a new function, which when congured can play an MP3 le on cancellation of a trigger, in Alternate

Playback mode only. On the micro SD card is a folder labelled “cancel” and inside this folder are the alert, evac and trigger

folders. To congure the unit for MP3 playback on trigger 3 cancellation for example, an MP3 le must be placed in the

trig3 folder (location K:\cancel\trig3).

5.0 Emergency tones (Alert and Evacuation)

The Alert and evacuation tones conform to Australian Standards AS1670.4 and are used to notify building occupants of

an emergency situation. Set DIP switch 2 to ON to activate the emergency tones.

Alert: The Alert tone is activated by a closing contact on the ALERT trigger

(Trigger10) and can be used in Alternate or Momentary setup as outlined in section

3.0. The Alert tone comes with a change over option which forces the A 1720C to

switch from Alert to the Evacuation tone after a prescribed time. Use the BCD switch

to adjust this time or switch off completely (see gure 6). Power down the A 1720C

for the changes to take effect.

Evacuation: The Evacuation tone is activated by a closing contact on the Evac

trigger (Trigger9) and can be used in Alternate or Momentary setup as mentioned in

section 3.0.

Alert and Evacuation messages: A message can be inserted every three alert

cycles and/or every three evac cycles. Refer to section 2.3 for more details.

Priority: The Emergency tones have priority over other triggers (1 to 8) and if

activated will stop any other MP3, and activate the selected emergency tone.

Evacuation also has priority over Alert. Fig 6.

6.0 Troubleshooting

NO Power (Power LED does not illuminate):

Make sure the power supply voltage is 12-30VDC.

Make sure the power supply is a DC input, not AC.

Emergency tones do not work:

Switch DIP1 switch 2 ON to activate emergency tones.

7.0 Specications

Power supply: ......................................................................12VDC to 30VDC 300mA (idle/maximum current draw 50mA)

Output: ...................................................................................................................................Stereo RCA 500mV nominal

Micro SD Card size: ....................................................................................................................................256MB to 32GB

Trigger Activation: .......................................................................................................................................Closing contact

MP3 info:

Bit rate: ....................................................................................................All standard MP3 rates (128kbps recommended)

Sample rate: .................................................................................................All standard MP3 rates (44kHz recommended)

Channels: ...................................................................................................................................................Stereo or mono

Switched Output Current Draw: ............................................................................................................. 200mA Maximum

* Specications subject to change without notice.