发明名称 Spurious ting suppression device particularly for auxiliary ringers in socket telephone systems
摘要 <p>An acoustic feedback suppression system, particularly for auxiliary ringers in socket telephone systems, comprising a first terminal (L1) and a second terminal (L2) of a telephone line, an internal ringer (9), and an auxiliary ringer (50) that is connected between said first and said second telephone lines; the particularity of the system is that it comprises activation means (12, 13) adapted to activate first (15) and second (16) switching means that reduce the voltage at the terminals of the auxiliary ringer (50), the activation means (12, 13) being controlled by an activation signal (14) generated by call, control, and signalling means (2) when a user dials a telephone number. &lt;IMAGE&gt;</p>
申请公布号 EP0756409(A1) 申请公布日期 1997.01.29
申请号 EP19950830338 申请日期 1995.07.28
申请人 STMICROELECTRONICS S.R.L. 发明人 CONSIGLIO, PIETRO;ANTONINI, CARLO
分类号 H04M1/74;H04M19/04;(IPC1-7):H04M1/74 主分类号 H04M1/74
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