JPH01139626U - - Google Patents
Info
- Publication number
- JPH01139626U JPH01139626U JP3627088U JP3627088U JPH01139626U JP H01139626 U JPH01139626 U JP H01139626U JP 3627088 U JP3627088 U JP 3627088U JP 3627088 U JP3627088 U JP 3627088U JP H01139626 U JPH01139626 U JP H01139626U
- Authority
- JP
- Japan
- Prior art keywords
- tuning
- trap
- circuit
- capacitance diode
- variable capacitance
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000003990 capacitor Substances 0.000 claims description 2
- 238000010586 diagram Methods 0.000 description 10
Landscapes
- Channel Selection Circuits, Automatic Tuning Circuits (AREA)
- Noise Elimination (AREA)
- Input Circuits Of Receivers And Coupling Of Receivers And Audio Equipment (AREA)
Description
第１図はこの考案の一実施例による選局回路の
構成および動作を示す図であり、第１図ａが選局
回路の回路図、第１図ｂがこの選局回路における
アンテナ同調回路のハイバンド時の等価回路図、
第１図ｃがこの選局回路におけるアンテナ同調回
路のローバンド時の等価回路図、第２図はこの考
案の一実施例による選局回路および従来の選局回
路におけるアンテナ同調回路の選択度特性を示し
た図、第３図はこの考案の一実施例による選局回
路および従来の選局回路におけるイメージ妨害比
を示した図、第４図は従来の選局回路の構成およ
び動作を示す図であり、第４図ａが選局回路の回
路図、第４図ｂがこの選局回路におけるアンテナ
同調回路のハイバンド時の等価回路図、第４図ｃ
がその選局回路におけるアンテナ同調回路のロー
バンド時の等価回路図である。
ＶＤ２…同調用可変容量ダイオード、ＶＤ３…
トラツプ用可変容量ダイオード、Ｃ８…トラツプ
補正コンデンサ、４…バンド選択電源、５…選局
電源。
FIG. 1 is a diagram showing the configuration and operation of a tuning circuit according to an embodiment of this invention. FIG. 1a is a circuit diagram of the tuning circuit, and FIG. 1b is a diagram of the antenna tuning circuit in this tuning circuit. Equivalent circuit diagram at high band,
Figure 1c is an equivalent circuit diagram of the antenna tuning circuit in this tuning circuit at low band, and Figure 2 shows the selectivity characteristics of the antenna tuning circuit in the tuning circuit according to an embodiment of this invention and in the conventional tuning circuit. Figure 3 is a diagram showing the image interference ratio in a tuning circuit according to an embodiment of this invention and a conventional tuning circuit, and Figure 4 is a diagram showing the configuration and operation of a conventional tuning circuit. Figure 4a is a circuit diagram of the tuning circuit, Figure 4b is an equivalent circuit diagram of the antenna tuning circuit in this tuning circuit at high band, and Figure 4c is
is an equivalent circuit diagram of the antenna tuning circuit in the tuning circuit in the low band mode. VD 2 ... Tuning variable capacitance diode, VD 3 ...
Trap variable capacitance diode, C8 ...trap correction capacitor, 4...band selection power supply, 5...tuning selection power supply.
Claims (1)
段と、同調用可変容量ダイオードに選局電圧を加
えて選局周波数を制御する選局手段とを備えた選
局回路において、 前記選局電圧が加えられるトラツプ用可変容量
ダイオードと、 前記バンド切り換え手段の切り換え操作によつ
て前記トラツプ用可変容量ダイオードに並列に接
続されるトラツプ補正コンデンサと からなる周波数可変トラツプ回路を備えた事を
特徴とする選局回路。[Claims for Utility Model Registration] A tuning circuit comprising a band switching means for switching a tuning frequency range, and a tuning means for controlling a tuning frequency by applying a tuning voltage to a tuning variable capacitance diode, comprising: A variable frequency trap circuit comprising a trap variable capacitance diode to which a channel selection voltage is applied, and a trap correction capacitor connected in parallel to the trap variable capacitance diode by switching operation of the band switching means. Features a tuning circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3627088U JPH01139626U (en) | 1988-03-18 | 1988-03-18 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3627088U JPH01139626U (en) | 1988-03-18 | 1988-03-18 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01139626U true JPH01139626U (en) | 1989-09-25 |
Family
ID=31262885
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3627088U Pending JPH01139626U (en) | 1988-03-18 | 1988-03-18 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01139626U (en) |
-
1988
- 1988-03-18 JP JP3627088U patent/JPH01139626U/ja active Pending