发明名称 |
TELEPHONE LINE CIRCUIT WITH DIFFERENTIAL LOOP CURRENT SENSING AND COMPENSATION |
摘要 |
<p>TELEPHONE LINE CIRCUIT WITH DIFFERENTIAL LOOP CURRENT SENSING AND COMPENSATION The invention provides a telephone line circuit in which the likelihood of exposing circuit devices in an associated switching facility to potentially damaging currents or voltages is greatly reduced. A repeat coil includes a primary winding for connection to a subscriber loop circuit. Direct loop current is maintained in the primary winding and the resulting d-c flux is compensated for by a regulator including a balancing winding. The core material in the repeat coil is saturable and limited in bulk to that sufficient to transmit normal a-c voice signals across the line circuit. Signals of a magnitude which cause the core material to saturate are thereby impeded in transmission across the line circuit. - i</p> |
申请公布号 |
CA1074034(A) |
申请公布日期 |
1980.03.18 |
申请号 |
CA19770288131 |
申请日期 |
1977.10.04 |
申请人 |
NORTHERN TELECOM LIMITED |
发明人 |
KORSKY, VINCENT V. |
分类号 |
H04M19/00;(IPC1-7):04M1/00;04M3/00;04M3/22 |
主分类号 |
H04M19/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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