DVG-5121SP User’s Manual
D-Link Corporation
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PSTN Switch Mode:
Select Auto Mode or Always PSTN from the drop-down menu.
Codec Priorities:
Use this field to select the type of voice coder/decoder (codec) priority you want to use.
G.711/ Ulaw: Operates at 64 Kbps (standard), 56 Kbps, and 48 Kbps (non-standard).
Compresses frames of 14-bit linear PCM samples into frames of 8-bit logarithmic PCM code
words.
G.711/ Alaw: Operates at 64 Kbps (standard), 56 Kbps, and 48 Kbps (non-standard).
Compresses 13-bit linear PCM samples into 8-bit logarithmic PCM code words.
G723.1: Operates at 6.3 Kbps and 5.3 Kbps. compression and decompression of 8 kHz speech signals.
G726: Operates at 40, 32, 24, and 16 Kbps.
G.729a/b: Operates on 10ms frames with short algorithm delays.
Compresses 8 kHz CODEC or linear audio data to 8 kbps.
iLBC:
Internet Low Bit Rate Codec (iLBC) is a royalty free narrowband speech codec. Operates at 15 to 20
Kbps.
G.723 Rate
: Select the G.723 rate from the drop-down menu.
iLBC mode
: Select the iLBC mode from the drop-down menu.
DTMF Method
: Choose what kind of pass through mode you want for the DTMF transmission.
Voice Active Detector:
Select an option for silence suppression from the drop-down menu.
Line Echo Canceller Tail Length:
G.168 is an ITU-T standard for eliminating the echo caused by the second by the
sound of your voice reverberating in the telephone receiver while calling.
Acoustic Echo Canceller Tail Length:
Acoustic echo is caused by direct and indirect feedback from speaker to
microphone. You can control the specific canceller tail length based on any
required local settings.
Automatic Gain Control Tx Level:
Select the gain transmission level from 0 to 30.
Automatic Gain Control Rx Level:
Select the gain transmission level from 0 to 30.
