ELTEX SMG-1016M, Operation Manual

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SMG Digital Gateway
leg). When unchecked, the complete list of selected codecs will be always transferred to SDP in
priority order.

ClearChannel-transit is a mode that allows to transfer RTP directly from the incoming connection
branch to the outgoing connection branch in SIP – SIP connection skipping internal switch buses of
the device and preserving RTP traffic including packetization time.
Digital gain

Rx gain (0.1 dB) – volume of a receiving signal, amplification/attenuation of the level of signal
received from an interacting gateway;

Tx gain (0.1 dB) – volume of a transmitting signal, amplification/attenuation of the level of signal
transmitted to an interacting gateway.
AGC (Auto Gain Control)

Compliance with ITU-T G.169 – when the option is enabled, the automatic amplification operates
in compliance with ITU-T G.169. The operation mode uses some algorithms different from the
recommendations, which provide better background noise suppresion in the absence of speech.
Rx gain settings

AGC master enable – enable automatic amplification of receiving signals;

Limit gain during double talk – limit a signal level if subscribers are talking simultaneously;

Signal reference gain, dBm0 – the level of the signal to which amplification will tend;

Signal maximum gain, dB – the maximum permissible value of the amplification of an original
signal ;

Signal minimum gain, dB – the minimum permissible value of the amplification of an original
signal;
Tx gain settings

AGC master enable – enable automatic amplification of transmitting signals;

Limit gain during double talk – limit a signal level if subscribers are talking simultaneously;

Signal reference gain, dBm0 – the level of the signal to which amplification will tend;

Signal maximum gain, dB – the maximum permissible value of the amplification of an original
signal;

Signal minimum gain , dB – the minimum permissible value of the amplification of an original
signal.
Dual-Tone Multi-Frequency signalling settings:

DTMF transport — method of DTMF transmission via IP network.
–
inband — in RTP packets, inband.
–
RFC2833 — in RTP packets according to RFC2833 recommendation.
–
SIP-INFO — outband, via SIP, INFO messages are used; at that, DTMF signal appearance
will depend on the MIME extension type.