DFT120 Digital Feedback Terminator Installation and Use Manual © 2003 Bogen Communications, Inc. All rights reserved. Specifications subject to change without notice.
© 2003 Bogen Communications, Inc. All Rights Reserved. Notice: Every effort was made to ensure that the information in this guide was complete and accurate at the time of printing. However, information is subject to change. FCC Statement (Part 15) - Radio Frequency Interference The Digital Feedback Terminator generates and uses radio frequency energy and if not installed and used in strict accordance with the manufacturer's instructions, may cause interference to radio and television reception.
Contents Overview ..........................................................................................................................................................................4 Features and Capabilities ..................................................................................................................................4 Specifications ....................................................................................................................................................
Overview Features and Capabilities The Digital Feedback Terminator has 4 minutes of available audio memory and can record up to 16 paging messages. A single page can have a maximum length of 1 minute. The unit can record new pages while playing back previously recorded pages. The DFT120 eliminates feedback over the paging system by opening the loop between the input microphone and the speakers.
Panel Descriptions Bottom Panel 1. Power - Input jack for power connection. 2. Override Input - RJ11 jack for both loop start and dry audio input sources. 3. Override Control Switch - Selects either dry loop (DL) or loop start (LS). 4. Page In Input - RJ11 jack for both dry audio and loop start applications. 5. Page In Control Switch - Selects either dry loop (DL) or loop start (LS). 6. Audio Out Volume Control - Output volume control. 7. Audio Out Impedance Selector - Selects either 8-ohm or 600-ohm. 8.
Installation Package Contents • • • • Digital Feedback Terminator Unit Power Pack, 12V DC Package of two 1/2" mounting wood screws Installation Manual You can mount the Digital Feedback Terminator on a wall, rack or table. Installation Steps These are the general steps for installation: 1. 2. 3. 4. 5. Mount the unit to the wall, rack or table. Make cable connections from the DFT120 to the PBX and the paging system. Set DIP switches to the desired operation. Power unit up. Test unit operation.
Operation There are three important functions that the Digital Feedback Terminator performs: 1. It eliminates feedback by recording the incoming page, then playing it back. 2. It is able to repeat a page once, allowing for a better response in noisy environments. 3. It is capable of stacking up to 16 incoming pages by recording incoming pages while playing back previously recorded pages, on a first-in, first-out basis.
Playing Back a Page The DFT120 can be configured to either automatically play back a recorded page announcement or to store recorded pages until directed to begin playing back these pages by some external device. The Play control on the I/O connector and setup switch 8 "Play Mode" control the method of playback. Selecting Automatic allows the DFT120 to operate without external signaling. Selecting Manual requires external triggering of page playback.
Connections and Switches Power Unit needs 12V DC, 1 Amp. Connect power pack supplied. Override Input 6-pin RJ11 style connector Pin Pin Pin Pin Pin Pin 1 2 3 4 5 6 Not used Override Control (+). Connect to Control (-) (Pin 5) to operate. Override Audio, Ring Override Audio, Tip Control (-) Not used Override Control Switch LOOP START (LS) Right Position - For operation with a Loop Start trunk. The DFT120 supplies the talk battery for loop current to start recording.
Audio Out Volume Control Controls the volume level delivered to the paging system. It is shipped with 1:1 gain factory set. Audio Out Impedance Selector Select the type of audio drive available at the Audio/Status connector. RIGHT POSITION for line level (600 ohms) and LEFT POSITION for power level (8 ohms). See Electrical Specifications section for maximum output levels.
DTMF Stripping DTMF tones recorded at the beginning of an audio message are typically used for zone control purposes. A repeated page should not have the zone control tones on the front end of the second page because the zone controller is already routed, therefore these tones will be stripped on any repeats of a page. Only DTMF tones at the beginning of the page would be handled in this fashion. Any DTMF tones recorded in the middle of the message would be recorded and played back in the typical manner.
Number of Plays The number of times which each message plays during the playback sequence can be selected. Choose from one or two times. If multiple messages were recorded into the queue, each message will play this number of times before the next message is played.
External I/O Connections and Control Five control inputs (Record, Play, Stop, Override, and Abort) are offered to the user for complete control over the recording and playback processes. None of these inputs are necessary when the DFT120 is operating automatically (setup switch 8, UP), but may be required based on system requirements. All of the control inputs are optically coupled so as to electrically isolate each activation initiated via contact closure or open collector driver.
Terminal Block, Output Signals All status outputs will be provided via relay contact closure. These contact closures will be provided via terminal block to the user. The name and description of each output is shown below. Busy Contact Normally Open contact closure becomes shorted whenever the DFT120 is processing a page. This would include the record and play processes, repeats and delays, recording playback tones, etc.
Example: System Setup and Connecting to the Paging System The DFT120 can be configured in several ways depending on the paging system used. The DFT120 is typically installed between the telephone system and the paging system. It interfaces with the paging controller in a zone paging environment, and with the amplifier in a single-zone installation.
Limited Warranty; Exclusion of Certain Damages The Bogen DFT120 Digital Feedback Terminator is warranted to be free from defects in material and workmanship for two (2) years from the date of sale to the original purchaser.