| 发明名称 |
AUTOMATIC VOICE-PATH SWITCHING CIRCUIT FOR A SPEAKER PHONE TELEPHONE SET |
| 摘要 |
A key telephone set incorporating a microphone and loudspeaker for hands-free telecommunication includes a circuit responsive to the difference between transmitted and received signal levels for switching the telephone set from transmitting to receiving mode and back again.
|
| 申请公布号 |
US3860756(A) |
申请公布日期 |
1975.01.14 |
| 申请号 |
US19730344218 |
申请日期 |
1973.03.23 |
| 申请人 |
NIPPON TSU SHIN KOGYO K.K. |
发明人 |
SHINOI, TSUYOSHI;MURAKAMI, TOYOSHIGE |
| 分类号 |
H04M1/60;H04M9/10;(IPC1-7):H04M9/08 |
主分类号 |
H04M1/60 |
| 代理机构 |
|
代理人 |
|
| 主权项 |
|
| 地址 |
|
