JPS59164346U

JPS59164346U - antenna circuit

Info

Publication number: JPS59164346U
Application number: JP5862883U
Authority: JP
Inventors: 村上　洋己
Original assignee: 株式会社富士通ゼネラル
Priority date: 1983-04-19
Filing date: 1983-04-19
Publication date: 1984-11-05

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Brief explanation of drawings]

第１図は従来のＦＭとＡＭのアンテナ端子が独立の場合
の電気回路図、第２図は従来のＦＭとＡＭのアンテナ端
子が共有の場合の電気回路図、第３図は本考案によるア
ンテナ回路の第１実施例の電気回路図、第４、図は本考
案の第２実施例の電気回路図、第５図に本考案の第３実
施例の電気回路図である。３・・・ＦＭ−ＡＭアンテナ端子、４・・・ＦＭ−ＡＭ
電源切換スイッチ、５・・・可動片、６・・・ＦＭ入力
回路、７・・・高周波増幅回路、９・・・ＡＭ同調回路
、１０・・・混合回路、２４・・・スイッチング回路、
２５・・・スイッチングトランジスタ、２６・・・ＡＭ
アンテナコイルミ４１・・・スイッチングダイオード。Figure 1 is an electric circuit diagram when the conventional FM and AM antenna terminals are independent, Figure 2 is an electric circuit diagram when the conventional FM and AM antenna terminals are shared, and Figure 3 is the antenna according to the present invention. FIG. 4 is an electrical circuit diagram of the first embodiment of the circuit, FIG. 4 is an electrical circuit diagram of the second embodiment of the present invention, and FIG. 5 is an electrical circuit diagram of the third embodiment of the present invention. 3...FM-AM antenna terminal, 4...FM-AM
Power supply selector switch, 5... Movable piece, 6... FM input circuit, 7... High frequency amplifier circuit, 9... AM tuning circuit, 10... Mixing circuit, 24... Switching circuit,
25... Switching transistor, 26... AM
Antenna coil Mi41...Switching diode.

Claims

[Scope of utility model registration request]

(1) In a radio receiver capable of receiving FM broadcasts and AM broadcasts, FM'-
an AM antenna terminal, an FM antenna input circuit directly connected to the FM-AM terminal, a switching circuit coupled to the FM-AM antenna terminal, and an AM antenna coil coupled to the switching circuit; An antenna circuit characterized in that a switching circuit is turned on when receiving AM and turned off when receiving FM.

(2) The antenna circuit according to claim 1, wherein the switching circuit includes a transistor and a bias circuit for the transistor, and the switching circuit controls the opening and closing of the transistor in conjunction with switching between FM and AM power supplies. .

(3) The switching circuit consists of a switching diode and a bias circuit for this diode, and the switching circuit is configured to control opening and closing of the diode in conjunction with switching between FM and AM power supplies. antenna circuit.

(4) The switching circuit consists of a mechanical switch, and F
The antenna circuit according to claim 1, which is a utility model, and is configured to control opening and closing of a switch in conjunction with switching between M and AM power sources.