发明名称 |
Energy detection circuit for a facsimile system controller. |
摘要 |
<p>Disclosed is an energy detection circuit for use in a facsimile system autodialer/controller. The circuit monitors a telephone line and nulls out transmit tones leaving only receive signals. The analog receive signals are processed to produce a digital signal indicating the on-off times of receive energy on the telephone line. The energy on-off times may then be evaluated by a microprocessor included in the facsimile system autodialer/controller to determine whether a dial tone, busy signal or ring back is being received.</p> |
申请公布号 |
EP0162634(A2) |
申请公布日期 |
1985.11.27 |
申请号 |
EP19850303267 |
申请日期 |
1985.05.09 |
申请人 |
UNISYS CORPORATION |
发明人 |
CARRASCO, FRANCIS P.;DEROME, GERARD A.;FERNEKES, DAVID W. |
分类号 |
H04M11/06;H04M11/00;H04N1/00;H04N1/40;H04Q1/446 |
主分类号 |
H04M11/06 |
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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