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81. 发明专利

JPS5527768A SIGNAL RECEPTION CIRCUIT 失效
公开(公告)号：JPS5527768A
公开(公告)日：1980-02-28
申请号：JP10108078
申请日：1978-08-18
申请人： MATSUSHITA ELECTRIC IND CO LTD
发明人： TANABE KENZOU , SERIZAWA MASABUMI
IPC分类号： H03J3/20 , H04B1/18
摘要： PURPOSE:To reduce the sensitivity change at the antenna circuit part to cover the entire tuning band as well as to prevent the disturbance by leading the pi-matching circuit between the antenna terminal and the 1st-step input amplifier via the LC circuit in the AM car radio set. CONSTITUTION:Variable capacity element C4 is provided at the antenna input circuit part in order to increase the input impedance at 1st-step amplification part A and to vary the frequency for selection and amplification. And fixed capacity element C3 featuring a larger capacity than the maximum value of element C4 is installed in parallel to the antenna terminal part, and as a result the variable range of the tuning frequency is increased to secure coverage over the entire band region. In addition, inductor L2 featuring the inductance suited to give a selective reception for the reception frequency range in cooperation with elements C3 and C4 is connected in parallel to the antenna terminal part, thus constitution the pi-matching circuit. Accordingly, the capacity of the parallel arrangement of C2 and C3 is shown by C23, and thus the sensitivity slope can be eliminated up to part A regardless of variation of C4 by increasing C23 more than the maximum value of C4. Furthermore, the cross modulation and the image disturbance can be avoided owing to the selective tuning circuit.

82. 发明专利

JPS5430601B2 失效
公开(公告)号：JPS5430601B2
公开(公告)日：1979-10-02
申请号：JP9573674
申请日：1974-08-20
IPC分类号： H05K9/00 , H03J1/00 , H03J3/20 , H04B1/06 , H04B1/08 , H05K1/00

83. 实用新型

JPS5416283Y2 失效
公开(公告)号：JPS5416283Y2
公开(公告)日：1979-06-27
申请号：JP1514674
申请日：1974-02-07
IPC分类号： H03J1/14 , F16H37/00 , G12B1/04 , H03J3/00 , H03J3/20

84. 实用新型

JPS5416282Y2 失效
公开(公告)号：JPS5416282Y2
公开(公告)日：1979-06-27
申请号：JP4781873
申请日：1973-04-20
IPC分类号： G01D5/02 , F16H7/04 , F16H7/12 , F16H19/02 , H03J1/00 , H03J1/10 , H03J3/20

85. 实用新型

JPS5459143U 失效
公开(公告)号：JPS5459143U
公开(公告)日：1979-04-24
申请号：JP13294577
申请日：1977-10-03
IPC分类号： H03J3/16 , H01F21/06 , H03J3/20

86. 实用新型

JPS5456166U 失效
公开(公告)号：JPS5456166U
公开(公告)日：1979-04-18
申请号：JP13002077
申请日：1977-09-27
IPC分类号： H05K1/14 , H03J1/06 , H03J3/16 , H03J3/20 , H05K1/18

87. 发明专利

JPS53120202A TUNING DEVICE 失效
公开(公告)号：JPS53120202A
公开(公告)日：1978-10-20
申请号：JP3453177
申请日：1977-03-30
申请人： HITACHI LTD
发明人： NAGASHIMA TOSHIO , MATSUURA SHIGEO , SAITOU TAKESHI
IPC分类号： H04B1/18 , H03J3/02 , H03J3/20 , H03J5/24
摘要： PURPOSE:To improve the attenuation properties at the image disturbance frequency as well as to reduce the insertion loss for a tuning device without narrowing the band width extremely.

88. 发明专利

JPS53101660A CAPACITANCE ADJUSTING DEVICE 失效
公开(公告)号：JPS53101660A
公开(公告)日：1978-09-05
申请号：JP1639177
申请日：1977-02-16
申请人： FUJITSU TEN LTD
发明人： SASAGAWA SADAJI
IPC分类号： H03J1/16 , H01G5/16 , H03J3/20

89. 发明专利

JPS5399812A FM TUNER 失效
公开(公告)号：JPS5399812A
公开(公告)日：1978-08-31
申请号：JP1516777
申请日：1977-02-14
申请人： MATSUSHITA ELECTRIC IND CO LTD
发明人： SUGANO MASASHI , TANABE KENZOU
IPC分类号： H03J7/02 , H03J3/20 , H03L7/06 , H04B1/26 , H04B1/28
摘要： PURPOSE:To make the IC-implementation easy and to maintain high performance, by using transistors and FETs.

90. 实用新型

JPS5396902U 失效
公开(公告)号：JPS5396902U
公开(公告)日：1978-08-07
申请号：JP12497477
申请日：1977-09-17
IPC分类号： F16H25/04 , F16H37/00 , G12B11/04 , H03J1/14 , H03J3/20

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