Bogen DFT120 User manual

Digital Feedback
Terminator
Model DFT120
Description
The Bogen DFT120 Digital Feedback Terminator provides high quality recording and playback of
audio pages. The DFT120 breaks the acoustical feedback loop created by the telephone handset and
paging speaker. The page is first recorded and then played back as soon as the source handset has
been put on-hook.
High capacity paging is accomplished by the DFT120’s record during playback and page stacking
capabilities. User selectable loop start trunk or 4 wire dry loop input interface and selectable 8 ohm
or 600 ohm output impedances allow the DFT120 to directly connect to a wide range of customer
premise equipment.
Features
• 120 Seconds of total audio memory.
• Record a message while another is being
played.
• Stack up to 8 messages for playback.
• Loop start or dry loop input modes.
• High sampling rate for excellent play quality.
• Multiple Record and Playback modes.
• Adjustable delay times between
messages.
• Message abort and stop control
available.
• Plugable terminal strip for easy
installation.
• Regeneration of zone control DTMF tones.
• Message repeat function.
• Pre-page tone available.
• Unit status outputs indicating, in-use, play and
record states.
• Selectable 8 or 600 ohm output
impedance.
• Transformer isolated audio output.
• Output power, 0.125W @ 8 ohms or
+4dBm @ 600 ohms.
• Automatic or externally controlled unit
operation.
• Strips message zone control DTMF tones
from the repeat message.
• DTMF controlled abort recording function.
Specifications subject to change without notice.
© 1998 Bogen Communications, Inc.
Part No. 54-7885-02 Printed in U.S.A. 9811

Audio Memory Capacity: 120 Seconds
Maximum Message Length: 30 Seconds
Message Stacking Capacity: 8 Messages
Audio Sampling: 12 Bit word at 16KHz
Frequency Response: 100Hz to 6.8KHz +/-3dB
Distortion: < 1.0% (THD max.)
Signal-to-Noise Ratio: 60 dBr
Dynamic Range: 60 dBr
Audio Input:
Type — Loop start trunk or 4-wire dry loop, switch selectable
Connector — RJ-11 (6 position)
Audio Output:
Type — Transformer isolated, unbalanced
Impedance / Power— 8 ohms / 0.125W or 600 ohms / +4dBm, switch selectable
Connector — RJ-11 (6 position)
Controls & Switches: Volume
Input type (loop start / dry loop)
Output impedance (8 or 600 ohm)
Setup dip switches (bank of 12)
External Control Inputs: Record, Play, Stop
Status Outputs: Record, Play, In Use
Status Contact Rating: 24VDC, 1A
LED Status Indicators: Power, Play, Record, In Use
Protective Fusing: 0.6A, Internal automatic reset
Power Consumption: 12VDC / 350 mA (typical)
Dimensions: 10”W x 1.5”H x 6.5”D
Shipping Weight: 6 lbs.
Technical
Specifications
Architects
and Engineers
Specifications
The feedback termination device shall be a model
DFT120, with 120 seconds of memory and the ability to
record up to 8 messages while simultaneously playing previ-
ously recorded messages. The device’s operation shall be
capable of automatic or external control.
The feedback terminator shall provide a frequency
response from 100Hz to 6.8KHz +/-3dB. Distortion shall be
less than 1% over its bandwidth. The messages shall have a
dynamic range of at least 60dBr and a signal to noise ratio of
at least 60dBr.
The feedback terminator shall accommodate both loop
start trunks and 4-wire dry loop interfaces, selectable by a
slide switch.The input connector style for the interface shall
be an RJ-11 type.
Further, the device shall provide an output capable of
either 8 ohm @ 0.125W or 600 ohms @ +4dBm, selectable
by slide switch. The output connector style for the interface
shall be an RJ-11 type. A control to adjust the output signal
level shall be provided.
A bank of dip switches shall be accessible to set device
operating features. The feedback terminator shall have the
ability to start recording based on dry loop, loop start, audio
triggered or DTMF activation methods. The device shall be
capable of stripping out of the recorded message in either the
beginning or anywhere in the message. The device shall be
able to regenerate DTMF tones in a message and to limit the
number of DTMF tones a message can contain before the
recording is aborted. The device shall allow for 2, 3, 4 or an
unlimited number of DTMF tones in a message. The device
shall allow a recording to be aborted by the issuance of 2
DTMF “#” digits in succession.
The selection of a pre-page tone shall be available. The
recorded message shall be able to automatically replay and
the time duration between message plays shall be selectable
as 1, 2, 5 or 10 seconds.
The feedback terminator shall have contact closures that
indicate if the unit is in use, playing and/or recording. An
internal jumper shall be able to set the contact for normally
open or normally closed operation.
The feedback terminator shall be wall mountable and
use an external power supply. The power supply shall be UL
and CSA listed and the entire product shall be backed by a
one-year warranty.
50 Spring Street, P.O. Box 575, Ramsey, New Jersey 07446
Tel. [phone], Fax: [phone], Web Site: http://www.bogen.com