DADS-PAS · Platform announcement system, 99 MP3 messages played on command over Ethernet

System overview

The DADS-PAS Platform Announcement System was developed as the next generation Wayside Announcement System. It accepts commands over its Ethernet connection, and the command protocol can be tailored to the user’s requirements. It holds up to 99 messages and hours of MP3 or WAV audio, all of them accessible from the Ethernet connection.

Audio is stored on non-volatile SD card memory, so no battery backup is needed. A front panel monitor speaker and pushbuttons let the user test the system locally and verify that the system and every message work as expected. The panels shown in the manual are labelled “DADS-A1310, Platform Paging System”.

• Shipped with: the DADS-PAS, the installation and user guide, an Ethernet cable, an RCA to RCA cable and rack mounting hardware.
• Optional accessory: a public address amplifier.

Installation

• Find an open 1U space in the 19″ rack.
• Mount the unit with its wiring at least 18″ away from power supplies or other equipment that generates electrical noise.
• Connect the audio outputs, then the control inputs and outputs.
• Connect and apply power, then test the unit’s operation.

Rear panel connections

• Power: 2-position Euro connector; position 1 is 12 VDC at 1 A, position 2 is ground.
• Ethernet: RJ45 connector; standard Ethernet cabling connects the DADS-PAS to the on-site network.
• Audio Out: RCA jack, single ended, line level output; centre pin positive, outer ring shield or negative.
• I/O Port: 6-position Euro connector, reserved for future use.
• Audio Out Level: potentiometer, from mute (fully counterclockwise) to +2 dB of gain (fully clockwise).
• The IP address is written on the rear of the unit.

Front panel controls and indicators

• Play All: momentary, lighted pushbutton; plays every message on the SD card once, from message #1 to the last, or until Stop. Its LED lights while a Play All sequence is active.
• Stop: momentary, lighted pushbutton; ends playback started by Play All or by an ATS triggered message. Its LED lights whenever the system is not playing a message.
• Speaker: maintained, lighted pushbutton; when pressed in, every message that plays is heard through the front panel monitor speaker, and its LED lights. When released, the monitor speaker is off.
• Volume: potentiometer for the monitor speaker level; clockwise is louder.
• Status LED: blinks at 2 Hz while the system is powered up and active.

Network interface and playback

Mackenzie programs the network configuration (IP address, gateway, subnet mask and so on) into each unit before shipping, as specified in documentation from the customer.

• Playback is triggered through the PAS interface; the play and stop commands are specified in the separate “ATS to PAS” document.
• Because the ATS actively manages the public address system, the DADS-PAS needs no message queuing or audio handshaking.
• A “Play” command received while a message is playing aborts that message at once and plays the new one.
• The audio output is a standard unbalanced connection, set with the rear panel level potentiometer.

Messages, memory and updates

• Messages are stored as .MP3 files in the DAVE directory of the SD card; message #1 is the file 1.MP3.
• Audio coding: MPEG 1 Layer 3 at 32 to 128 kbps, or 16-bit WAV; frequency response 50 Hz to 15 kHz, 80 dB dynamic range.
• The device supports no sentences or playlists.
• Future changes to the announcements can be loaded from a USB memory key on the front panel, by a procedure Mackenzie provides when needed.
• A front panel slot behind a cover plate lets the user remove and replace the SD card (2 GB or larger).
• There are no user-serviceable parts inside; refer all servicing to the factory.