JPH0424885B2 - - Google Patents
Info
- Publication number
- JPH0424885B2 JPH0424885B2 JP56174496A JP17449681A JPH0424885B2 JP H0424885 B2 JPH0424885 B2 JP H0424885B2 JP 56174496 A JP56174496 A JP 56174496A JP 17449681 A JP17449681 A JP 17449681A JP H0424885 B2 JPH0424885 B2 JP H0424885B2
- Authority
- JP
- Japan
- Prior art keywords
- tuning
- capacitor
- voltage
- variable capacitance
- controlled variable
- 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.)
- Expired - Lifetime
Links
- 239000003990 capacitor Substances 0.000 claims description 30
- 230000000694 effects Effects 0.000 description 5
- 230000007423 decrease Effects 0.000 description 3
- 230000006866 deterioration Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000005236 sound signal Effects 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H03—ELECTRONIC CIRCUITRY
- H03J—TUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS
- H03J3/00—Continuous tuning
- H03J3/02—Details
- H03J3/16—Tuning without displacement of reactive element, e.g. by varying permeability
- H03J3/18—Tuning without displacement of reactive element, e.g. by varying permeability by discharge tube or semiconductor device simulating variable reactance
- H03J3/185—Tuning without displacement of reactive element, e.g. by varying permeability by discharge tube or semiconductor device simulating variable reactance with varactors, i.e. voltage variable reactive diodes
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、電圧制御可変容量ダイオードとコン
デンサまたは第２の電圧制御可変容量ダイオード
との直列回路をコイルと並列に接続し、上記電圧
制御可変容量ダイオードと上記コンデンサあるい
は第２の電圧制御可変容量ダイオードとの接続点
を抵抗を介して同調電圧入力端に接続した電子同
調回路に関する。[Detailed Description of the Invention] [Field of Industrial Application] The present invention provides a series circuit of a voltage controlled variable capacitance diode and a capacitor or a second voltage controlled variable capacitance diode connected in parallel with a coil, The present invention relates to an electronic tuning circuit in which a connection point between a capacitance diode and the capacitor or a second voltage-controlled variable capacitance diode is connected to a tuning voltage input terminal via a resistor.
第１図のＡ〜Ｃは従来のこの種の電子同調回路
の例を示したもので、同図(A)は電圧制御可変容量
ダイオード２とコンデンサ１の直列回路をコイル
３と並列に接続されており、この電圧制御可変容
量ダイオード２とコンデンサ１との接続点が抵抗
４あるいはコイル５を介して同調電圧入力端VT
に接続されている。
Figures A to C in Figure 1 show examples of conventional electronic tuning circuits of this type. Figure 1 (A) shows a series circuit of a voltage-controlled variable capacitance diode 2 and a capacitor 1 connected in parallel with a coil 3. The connection point between voltage controlled variable capacitance diode 2 and capacitor 1 is connected to tuning voltage input terminal V T via resistor 4 or coil 5.
It is connected to the.
同図Ｂは上記Ａ図におけるコイル３の他端を接
地するようにしたものであり、同図ＣはＡ図、Ｂ
図におけるコンデンサ１を他の電圧制御可変容量
ダイオード６に置換えたものである。 Figure B shows the other end of the coil 3 in Figure A being grounded, and Figure C shows Figure A and Figure B.
The capacitor 1 in the figure is replaced with another voltage-controlled variable capacitance diode 6.
これら従来の電子同調回路においては、上記同
調電圧入力端VTに印加する同調制御電圧を変化
させることによつて電圧制御可変容量ダイオード
２，６の容量を変化させ、これによつてコイル３
とこの電圧制御可変容量ダイオード２，６および
コンデンサ１とからなる同調回路の同調周波数を
変化させている。 In these conventional electronic tuning circuits, the capacitance of the voltage-controlled variable capacitance diodes 2 and 6 is changed by changing the tuning control voltage applied to the tuning voltage input terminal VT , and thereby the coil 3
The tuning frequency of the tuning circuit consisting of the voltage-controlled variable capacitance diodes 2 and 6 and the capacitor 1 is changed.
しかしながら、この同調制御電圧を印加する回
路のインピーダンスが高いために、交流電源から
の商用周波数の電圧変動や電源回路のインピーダ
ンスによつて生じる音声出力による電圧変動など
がこの同調制御電圧に重畳されて、同調周波数を
変化させて音質の悪化を生じたりＳ／Ｎ比を低下
させてしまうという問題があつた。
However, because the impedance of the circuit that applies this tuning control voltage is high, voltage fluctuations at the commercial frequency from the AC power supply and voltage fluctuations due to audio output caused by the impedance of the power supply circuit are superimposed on this tuning control voltage. However, there were problems in that changing the tuning frequency resulted in deterioration of sound quality and a decrease in the S/N ratio.
本発明は、この同調制御電圧に重畳される信
号、特に、電源からの商用周波数やその高調波あ
るいは音声信号などの低周波数信号による同調周
波数の変化を生じないようにした電子同調回路を
得ることを目的とする。 The present invention aims to obtain an electronic tuning circuit which prevents changes in tuning frequency caused by signals superimposed on this tuning control voltage, particularly low frequency signals such as commercial frequencies from power sources, their harmonics, or audio signals. With the goal.
第２図の実施例に示すように、電圧制御可変容
量ダイオード２とコンデンサ１または第２の電圧
制御可変容量ダイオード６との直列回路をコイル
３と並列に接続し、上記電圧制御可変容量ダイオ
ード２と上記コンデンサ１または電圧制御可変容
量ダイオード６との接続点を抵抗を介して同調電
圧入力端VTに接続した電子同調回路において、
上記コイル３の一方の端子を抵抗９およびコンデ
ンサ８の並列回路を介して接地するとともに大容
量のコンデンサ７を介して上記同調電圧入力端
VTに接続するようにした。
As shown in the embodiment of FIG. 2, a series circuit of a voltage controlled variable capacitance diode 2 and a capacitor 1 or a second voltage controlled variable capacitance diode 6 is connected in parallel with the coil 3, and the voltage controlled variable capacitance diode 2 is connected in parallel with the coil 3. In an electronic tuning circuit in which the connection point between the capacitor 1 or the voltage-controlled variable capacitance diode 6 is connected to the tuning voltage input terminal V T via a resistor,
One terminal of the coil 3 is grounded through a parallel circuit of a resistor 9 and a capacitor 8, and a large capacity capacitor 7 is connected to the tuning voltage input terminal.
I connected it to V T.
第１図Ａに示した従来の電子同調回路に本発明
を適用した第２図Ａの実施例を参照して説明する
と、電圧制御可変容量ダイオード２とコンデンサ
１の直列回路と並列に接続されているコイル３の
一端をコンデンサ８および抵抗９の並列回路を経
て接地するとともに、同調電圧入力端VTとこの
コイル３の一端との間を大容量のコンデンサ７を
介して接続してある。なお、このコンデンサ８は
コイル３の一端を高周波的に接地して動作を安定
化するためのものであり、抵抗９は電圧制御可変
容量ダイオード２から接地への直流電路および前
記大容量のコンデンサ７を経た低周波分の帰路を
構成するものである。
Referring to the embodiment shown in FIG. 2A in which the present invention is applied to the conventional electronic tuning circuit shown in FIG. One end of the coil 3 is grounded via a parallel circuit of a capacitor 8 and a resistor 9, and the tuning voltage input terminal V T and one end of the coil 3 are connected via a large capacity capacitor 7. Note that this capacitor 8 is for stabilizing the operation by grounding one end of the coil 3 at high frequency, and the resistor 9 is for connecting the DC current path from the voltage-controlled variable capacitance diode 2 to the ground and the large-capacity capacitor 7. This constitutes the return path for the low frequency components that have passed through the .
また、図から明らかなように、上記電圧制御可
変容量ダイオード２とコンデンサ１との接続点が
抵抗４あるいはコイル５を介して同調電圧入力端
VTに接続されることは従来例におけると同様で
ある。 Further, as is clear from the figure, the connection point between the voltage controlled variable capacitance diode 2 and the capacitor 1 is connected to the tuning voltage input terminal via the resistor 4 or the coil 5.
The connection to V T is the same as in the conventional example.
この構成によれば、同調電圧入力端VTに印加
された不所望の交流信号は、上記大容量のコンデ
ンサ７を介して抵抗９およびコンデンサ８の並列
回路を経て接地されるので、コンデンサ１、電圧
制御可変容量ダイオード２およびコイル３からな
る同調回路全体の電位を変化させる。 According to this configuration, the undesired AC signal applied to the tuning voltage input terminal V T is grounded via the large capacity capacitor 7 and the parallel circuit of the resistor 9 and the capacitor 8. The potential of the entire tuned circuit consisting of the voltage controlled variable capacitance diode 2 and the coil 3 is changed.
このとき、この同調電圧入力端VTに印加され
た不所望の交流信号は、抵抗４あるいはこれに置
換られるコイル５（第１図Ａ参照）を経て電圧制
御可変容量ダイオード２のカソードにも同相で印
加されるから、電圧制御可変容量ダイオード２の
端子間電圧は変化せず、したがつて、この同調回
路の同調周波数には影響を及ぼさないので、この
同調回路の同調周波数が変動することによる音質
の悪化やＳ／Ｎ比の低下は生じなくなる。 At this time, the undesired alternating current signal applied to this tuning voltage input terminal V Since the applied voltage is applied at Deterioration of sound quality and deterioration of S/N ratio will no longer occur.
しかしながら、同調制御電圧は直流であるため
に上記コンデンサ７によつて遮断されて同調回路
全体の電位を変化させることはないが、この同調
電圧入力端VTに印加された同調制御電圧は、電
圧制御可変容量ダイオード２、コイル３、抵抗９
を経て接地に至るので、この電圧制御可変容量ダ
イオード２の端子電圧はこの同調制御電圧に応じ
て変化し、同調回路の同調周波数を調整すること
ができる。 However, since the tuning control voltage is a direct current, it is blocked by the capacitor 7 and does not change the potential of the entire tuning circuit, but the tuning control voltage applied to the tuning voltage input terminal V T Control variable capacitance diode 2, coil 3, resistor 9
Since the terminal voltage of the voltage controlled variable capacitance diode 2 changes according to the tuning control voltage, the tuning frequency of the tuning circuit can be adjusted.
第２図ＢおよびＣは、それぞれ第１図Ｂおよび
Ｃに示した従来例に本発明を適用した実施例を示
しており、いずれも上記した第２図Ａの実施例に
おけると同様に、同調電圧入力端VTに印加され
た低周波信号はコンデンサ７を介してコイル３と
電圧制御可変容量ダイオード２，６あるいはコン
デンサ１からなる同調回路全体の電位を変動させ
るが、この同調回路の同調周波数には影響を及ぼ
さないので、本発明所期の効果を達成することが
できる。
FIGS. 2B and 2C show an embodiment in which the present invention is applied to the conventional example shown in FIGS. 1B and 1C, respectively. The low frequency signal applied to the voltage input terminal V T changes the potential of the entire tuned circuit consisting of the coil 3 and the voltage controlled variable capacitance diodes 2 and 6 or the capacitor 1 via the capacitor 7, but the tuning frequency of this tuned circuit varies. Since this has no effect on the above, the desired effect of the present invention can be achieved.
本発明においては、同調回路と接地間に付加し
たコンデンサ８を同調制御電圧によつて充電する
ため、このコンデンサ８と抵抗９とによる時定数
に応じて電圧制御可変容量ダイオード２の容量変
化の応答速度が低下する。 In the present invention, since the capacitor 8 added between the tuning circuit and the ground is charged by the tuning control voltage, the response of the capacitance change of the voltage-controlled variable capacitance diode 2 is determined according to the time constant of the capacitor 8 and the resistor 9. Speed decreases.
第３図はこの応答速度の低下の影響を避けるよ
うにした本発明の他の実施例を示すもので、同調
操作を行つている期間中、トランジスタ１０を導
通させてコンデンサ８と抵抗９とを短絡するよう
にしたものである。 FIG. 3 shows another embodiment of the present invention which avoids the influence of this reduction in response speed, in which the transistor 10 is made conductive and the capacitor 8 and resistor 9 are connected during the tuning operation. It is designed to short circuit.
このトランジスタ１０のベースには、同調操作
期間中発生する信号、例えばミユート信号を印加
するようにしておくことによつて上記コンデンサ
８と抵抗９の並列回路を短絡させ、同調動作中に
おいては従来例におけると同様な回路構成となる
ようにして同調周波数の変化速度の低下を避ける
ことができる。 By applying a signal generated during the tuning operation, for example, a mute signal, to the base of the transistor 10, the parallel circuit of the capacitor 8 and the resistor 9 is short-circuited. It is possible to avoid a decrease in the speed of change of the tuning frequency by adopting a circuit configuration similar to that in .
本発明によれば、電源からの商用周波数やその
高調波、あるいは音声出力などによる同調周波数
の変動を受けることのない電子同調回路を得るこ
とができるという格別の効果が達成される。
According to the present invention, a special effect is achieved in that an electronic tuning circuit can be obtained that is free from fluctuations in tuning frequency due to commercial frequency from a power source, its harmonics, or audio output.
第１図は従来例を示す図、第２図は本発明の実
施例を示す図、第３図は本発明の他の実施例を示
す図である。
１……コンデンサ、２，６……電圧制御可変容
量ダイオード、３……コイル、８……コンデン
サ、９……抵抗。
FIG. 1 is a diagram showing a conventional example, FIG. 2 is a diagram showing an embodiment of the present invention, and FIG. 3 is a diagram showing another embodiment of the present invention. 1... Capacitor, 2, 6... Voltage controlled variable capacitance diode, 3... Coil, 8... Capacitor, 9... Resistor.
Claims (1)
たは第２の電圧制御可変容量ダイオードとの直列
回路をコイルと並列に接続し、上記電圧制御可変
容量ダイオードと上記コンデンサまたは第２の電
圧制御可変容量ダイオードとの接続点を抵抗を介
して同調電圧入力端に接続した電子同調回路にお
いて、 上記コイルの一方の端子を、抵抗およびコンデ
ンサの並列回路を介して接地するとともに大容量
のコンデンサを介して上記同調電圧入力端に接続
するようにしたことを特徴とする電子同調回路。[Claims] 1. A series circuit of a voltage controlled variable capacitance diode and a capacitor or a second voltage controlled variable capacitance diode is connected in parallel with a coil, and the voltage controlled variable capacitance diode and the capacitor or a second voltage controlled variable capacitance diode are connected in parallel with each other. In an electronic tuning circuit in which the connection point with the variable capacitance diode is connected to the tuning voltage input terminal via a resistor, one terminal of the above coil is grounded via a parallel circuit of a resistor and a capacitor, and a large capacity capacitor is connected. An electronic tuning circuit characterized in that the electronic tuning circuit is connected to the tuning voltage input terminal.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17449681A JPS5877315A (en) | 1981-11-02 | 1981-11-02 | Electronic tuning circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP17449681A JPS5877315A (en) | 1981-11-02 | 1981-11-02 | Electronic tuning circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5877315A JPS5877315A (en) | 1983-05-10 |
| JPH0424885B2 true JPH0424885B2 (en) | 1992-04-28 |
Family
ID=15979500
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP17449681A Granted JPS5877315A (en) | 1981-11-02 | 1981-11-02 | Electronic tuning circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5877315A (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS51130101A (en) * | 1975-05-06 | 1976-11-12 | Matsushita Electric Ind Co Ltd | Tuner |
-
1981
- 1981-11-02 JP JP17449681A patent/JPS5877315A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS51130101A (en) * | 1975-05-06 | 1976-11-12 | Matsushita Electric Ind Co Ltd | Tuner |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5877315A (en) | 1983-05-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3835399A (en) | Adjustable electronic tunable filter with simulated inductor | |
| US4393353A (en) | Negative feedback amplifying circuit having voltage negative feedback and current negative feedback circuits | |
| US3539826A (en) | Active variable impedance device for large signal applications | |
| SU1103812A3 (en) | Variable gain amplifier | |
| JPH04501792A (en) | temperature stable oscillator | |
| JPH0424885B2 (en) | ||
| US3174111A (en) | Twin-t filter with negative feedback | |
| JP3072003B2 (en) | Active bandpass filter | |
| US3614667A (en) | Switchable and modulatory crystal oscillator | |
| US2197239A (en) | Stabilized tuned system | |
| US2803758A (en) | Transistor amplifier clipping circuit | |
| US3775698A (en) | A circuit for generating a high power rf signal having low am and fm noise components | |
| US3151302A (en) | Automatic gain control circuit utilizing voltage variable capacitor | |
| US3343099A (en) | Audio compressor circuit | |
| US3323078A (en) | Transistorized bounce compensated remote variable gain control | |
| US3826999A (en) | Fsk oscillator | |
| JPH0241934Y2 (en) | ||
| US4136289A (en) | Phase control circuit and oscillator circuit using it | |
| US2899648A (en) | Vibrato | |
| US2888526A (en) | Peak and notch filters including active elements | |
| JPS6236332Y2 (en) | ||
| US3636382A (en) | Automatic delay equalizer | |
| US3373371A (en) | Vhf tuner neutralizing circuit | |
| JPH056363B2 (en) | ||
| US2896171A (en) | Oscillator |