TG100:1 GSM or 3G Channel . TG200: 2 GSM or 3G or 4G Channels . TG400: 4 GSM or 3G or 4G Channels . TG800: 8 GSM or 3G or 4G Channels . TG1600: 16 GSM or 3G Channels . Voice Codec: G.711 (alaw/ulaw), G.722, G.726, G.729A, GSM, ADPCM, Speex.
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