发明名称 Radio telephone with variable attenuator for controlling modulated signal
摘要 A variable attenuating circuit is provided between a control circuit of a radio telephone and a transmitter to control the level of the control signal to either terminate or hold the speech when either the speech terminating or the holding operation is performed. When the control signal for either speech termination or speech holding is transmitted from the radio telephone to a base unit, the degree of attenuation by the attenuating circuit is controlled so as to be reduced. Thus, the level of the control signal in the transmitter is controlled to thereby reduce the level of the control signal leaking possibly to the cable telephone line. When the base unit cannot receive the control signal to either terminate or hold the speech, it restores the original degree of attenuation of the attenuating circuit and again sends the control signal to either terminate or hold the speech.
申请公布号 US5046081(A) 申请公布日期 1991.09.03
申请号 US19900492927 申请日期 1990.03.13
申请人 KABUSHIKI KAISHA TOSHIBA 发明人 UMEMOTO, YUJI
分类号 H04M1/00;H04M1/725;H04Q7/38 主分类号 H04M1/00
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