カバーされていない 2 つのキーの繊維強化プラスチック電話

Telephone system: DTMF
Incoming call ringing signal light prompt;
Ring pressure: ≥ 70dB(A);
Call connection time≤6S (non-blocking);
The maximum communication distance is 5km;
Classified rated sound pressure level intensity: ≥90dBA;
Audio range: 300Hz ~ 3400Hz;
Harmonic distortion: ≤ 5%;
DTMF call system;
Rated feed voltage: DC48V/DC24V;
Sending/receiving frequency response: in line with GB/T15279-2002;
Transmit Loudness Rating (SLR): 5 ~ 15dB;
Received Loudness Rating (RLR): -7 ~ 2dB;
Sidetone Masking Rating (STMR): ≥7dB;
The system has strong expansion compatibility and supports standard SIP 2.0 (RFC3261) and related RFC protocols;
Support: TCP/UDP, HTTP, ARP/RARP, DNS, NTP, TFTP, TELNET;
Multiple voice coding methods such as G.729, G.723, G.711, G.722, G.726 are optional;
DTMF mode RFC2833, SIP INFO, INBAND;
Support static IP address modification, DNS domain name resolution;
Support one-key direct call dispatcher function and SOS emergency call;
Provide alarm, monitoring, intercom, broadcast functions;
Full-duplex intercom function;
Adopt advanced echo cancellation technology;
Speaker sensitivity can be adjusted;
The system provides recording and recording output, and can call and query recording files at any time;
Can be set through WEB interface;
Online software update