User`s manual

SIP User's Manual 312 Document #: LTRT-65411
MediaPack Series
Note: The Prerecorded tones are used only for generation of tones. Detection of
tones is performed according to the CPT file.
The PRT is a *.dat file containing a set of prerecorded tones that can be played by the
device. Up to 40 tones (totaling approximately 10 minutes) can be stored in a single PRT
file on the device's flash memory. The prerecorded tones are prepared offline using
standard recording utilities (such as CoolEdit
TM
) and combined into a single file using
AudioCodes' TrunkPack Downloadable Conversion utility (refer to the Product Reference
Manual).
The raw data files must be recorded with the following characteristics:
 Coders: G.711 A-law or G.711 µ-law
 Rate: 8 kHz
 Resolution: 8-bit
 Channels: mono
The generated PRT file can then be loaded to the device using AudioCodes' BootP/TFTP
utility or the Web interface (refer to ''Loading Auxiliary Files'' on page 210).
The p
rerecorded tones are played repeatedly. This allows you to record only part of the
tone and then play the tone for the full duration. For example, if a tone has a cadence of 2
seconds on and 4 seconds off, the recorded file should contain only these 6 seconds. The
PRT module repeatedly plays this cadence for the configured duration. Similarly, a
continuous tone can be played by repeating only part of it.
6.4 Coefficient File
The Coeff_FXS.dat file is used to provide best termination and transmission quality
adaptation for different line types for FXS interfaces. This adaptation is performed by
modifying the telephony interface characteristics (such as DC and AC impedance, feeding
current, and ringing voltage). The coeff.dat auxiliary file is produced specifically for each
market after comprehensive performance analysis and testing, and can be modified on
request. The current file supports US line type of 600 ohm AC impedance and 40 V RMS
ringing voltage for REN = 2. To load the coeff.dat file to the device, use the Web interface
or specify the FXS coeff.dat file name in the device's ini file (refer to ''Loading Auxiliary
Files'' on page 210).
The Coeff.dat file consists of a set of parameters for the signal processor of the loop
interface devices. This parameter set provides control of the following AC and DC interface
parameters:
 DC (battery) feed characteristics
 AC impedance matching
 Transmit gain
 Receive gain
 Hybrid balance
 Frequency response in transmit and receive direction
 Hook thresholds
 Ringing generation and detection parameters