JPS62280Y2 - - Google Patents
Info
- Publication number
- JPS62280Y2 JPS62280Y2 JP1770680U JP1770680U JPS62280Y2 JP S62280 Y2 JPS62280 Y2 JP S62280Y2 JP 1770680 U JP1770680 U JP 1770680U JP 1770680 U JP1770680 U JP 1770680U JP S62280 Y2 JPS62280 Y2 JP S62280Y2
- Authority
- JP
- Japan
- Prior art keywords
- varactor
- pin diode
- input
- primary winding
- input transformer
- 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
Links
- 238000004804 winding Methods 0.000 claims description 21
- 239000003990 capacitor Substances 0.000 description 8
- 230000005684 electric field Effects 0.000 description 6
- 238000010586 diagram Methods 0.000 description 3
- 230000003321 amplification Effects 0.000 description 2
- 230000002238 attenuated effect Effects 0.000 description 2
- 230000007423 decrease Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000009429 electrical wiring Methods 0.000 description 2
- 238000003199 nucleic acid amplification method Methods 0.000 description 2
- 230000000903 blocking effect Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
Landscapes
- Control Of Amplification And Gain Control (AREA)
- Input Circuits Of Receivers And Coupling Of Receivers And Audio Equipment (AREA)
Description
【考案の詳細な説明】
この考案は入力トランスの１次側巻線がバラク
タを介してアンテナに結合されるバラクタ同調式
AMラジオ受信機に関するものである。[Detailed explanation of the invention] This invention is a varactor-tuned type in which the primary winding of the input transformer is coupled to the antenna via a varactor.
It concerns AM radio receivers.
AMラジオ受信機の入力回路にバラクタを用い
て入力同調式に構成することは、容量性のアンテ
ナに適合する利点を有するけれども、このバラク
タが共振コンデンサとして活用されるため、アン
テナに誘起される入力信号がバラクタに直接かか
り、強電界入力信号の場合、信号歪や混変調など
の要因となる。 Using a varactor in the input circuit of an AM radio receiver to configure the input tuning type has the advantage of being compatible with a capacitive antenna, but since this varactor is utilized as a resonant capacitor, the input voltage induced in the antenna The signal is applied directly to the varactor, and in the case of a strong electric field input signal, this can cause signal distortion and cross-modulation.
この考案は上記の欠点を改善するために、入力
トランスの１次側もしくは２次側巻線にピンダイ
オードを接続し、入力信号に比例してこのダイオ
ードへの順方向電流を増減させることにより、入
力同調回路のインピーダンスを増減させ、強電界
入力信号を減衰させて信号歪や混変調などを防止
できるバラクタ同調式AMラジオ受信機を提供す
ることを目的とする。 In order to improve the above-mentioned drawbacks, this invention connects a pin diode to the primary or secondary winding of the input transformer, and increases or decreases the forward current to this diode in proportion to the input signal. The purpose of the present invention is to provide a varactor-tuned AM radio receiver that can prevent signal distortion and cross-modulation by increasing or decreasing the impedance of an input tuning circuit and attenuating strong electric field input signals.
以下、この考案の実施例を図面にしたがつて説
明する。 Embodiments of this invention will be described below with reference to the drawings.
第１図は、この考案に係るバラクタ同調式AM
ラジオ受信機の入力回路部の一例を示す電気回路
図で、同図中、１は信号源２、抵抗３、有効容量
４および無効容量５からなる容量性のAMアンテ
ナ等価回路、６は入力トランス７の１次側巻線８
に直列接続されたバラクタ、９，１０はこのバラ
クタ６の両端において１次側巻線８に並列接続さ
れたトリマコンデンサで、トリマコンデンサ１０
はトラツキング補正用である。入力トランス７は
１対の２次側巻線１１，１２を有し、一方の２次
側巻線１１には直流遮断用コンデンサ１８を介し
て高周波増幅用トランジスタ１４のベースが接続
され、他方の２次側巻線１２にはピンダイオード
１５とバイパス用コンデンサ１６とが直列接続さ
れ、このピンダイオード１５の回路に自動利得制
御（AGC）電圧を印加するためのAGC増幅器１
７が接続されている。 Figure 1 shows a varactor-tuned AM according to this invention.
This is an electric circuit diagram showing an example of the input circuit section of a radio receiver. In the figure, 1 is a capacitive AM antenna equivalent circuit consisting of a signal source 2, a resistor 3, an effective capacitor 4, and a reactive capacitor 5, and 6 is an input transformer. 7 primary winding 8
9 and 10 are trimmer capacitors connected in parallel to the primary winding 8 at both ends of the varactor 6.
is for tracking correction. The input transformer 7 has a pair of secondary windings 11 and 12, one of which is connected to the base of a high-frequency amplification transistor 14 via a DC blocking capacitor 18, and the other A pin diode 15 and a bypass capacitor 16 are connected in series to the secondary winding 12, and an AGC amplifier 1 is used to apply an automatic gain control (AGC) voltage to the circuit of the pin diode 15.
7 is connected.
上記アンテナ等価回路１、バラクタ６およびト
リマコンデンサ９，１０からなる総合容量と、入
力トランス７の１次側巻線８における巻数n1で示
されるインダクタンスとで受信周波数に共振す
る。この共振状態において、強電界入力信号が受
信されると、AGC電圧が上昇し、AGC増幅器１
７の出力電圧が高くなり、ピンダイオード１５の
順方向電流が入力信号に比例して増大し、上記バ
ラクタ６を含む入力同調回路１８での損失が増
し、強電界入力信号を減衰させることができる。
これにより、強電界入力信号の受信時においてバ
ラクタ同調回路１８を用いた場合の信号歪や混変
調などを有効に防止することができる。 The total capacitance consisting of the antenna equivalent circuit 1, the varactor 6, and the trimmer capacitors 9 and 10, and the inductance represented by the number of turns n1 in the primary winding 8 of the input transformer 7 resonate at the reception frequency. In this resonant state, when a strong electric field input signal is received, the AGC voltage increases and the AGC amplifier 1
7 becomes higher, the forward current of the pin diode 15 increases in proportion to the input signal, the loss in the input tuning circuit 18 including the varactor 6 increases, and the strong electric field input signal can be attenuated. .
Thereby, it is possible to effectively prevent signal distortion, cross-modulation, etc. when using the varactor tuning circuit 18 when receiving a strong electric field input signal.
ところで、ピンダイオード１５は約10mAの電
流を流すと数オームの低抵抗値となり、電流を遮
断するとほぼ無限大の抵抗値となり、どの電流領
域でも直線性の良いものが市販されており、信号
歪および混変調を防止する上できわめて有効であ
る。また、入力トランス７の１次側巻線８と２次
側巻線１２との巻数比n1／n3は約５程度であるこ
とが推奨され、これが１程度である場合、入力信
号の減衰量、つまりAGCダイナミツク幅は大き
くなるが、ピンダイオード１５に過大の入力信号
がかかりすぎて、かえつて歪の原因となる。ま
た、巻数比n1／n3が十分に大きくなりすぎると、
ピンダイオード１５による入力信号の減衰量がと
れず、AGC効果がうすれる。 By the way, the pin diode 15 has a low resistance value of several ohms when a current of about 10 mA is passed through it, and has an almost infinite resistance value when the current is cut off. Diodes with good linearity in any current range are commercially available, and they do not cause signal distortion. and is extremely effective in preventing cross-modulation. In addition, it is recommended that the turns ratio n 1 /n 3 between the primary winding 8 and the secondary winding 12 of the input transformer 7 is about 5, and if this is about 1, the input signal will be attenuated. Although the amount, that is, the AGC dynamic width increases, too much input signal is applied to the pin diode 15, which causes distortion. Also, if the turns ratio n 1 /n 3 becomes too large,
The amount of attenuation of the input signal by the pin diode 15 cannot be taken, and the AGC effect is weakened.
上記実施例においては、高周波増幅用トランジ
スタ１４とピンダイオード１５とが、入力トラン
ス７の１対の２次側巻線１１，１２の個別回路に
それぞれ接続されていたけれども、第２図および
第３図に示すように上記巻線１１，１２を共通巻
線にしてもよい。第２図の場合、トランジスタ１
４が電流駆動形であるため、ステツプアツプ形式
でピンダイオード１５が接続され、また第３図の
場合、トランジスタ１４が電圧駆動形としての
FETであるため、２次側巻線１１のインピーダ
ンスが高くなるので、ピンダイオード１５はステ
ツプダウン形式で接続されている。 In the above embodiment, the high frequency amplification transistor 14 and the pin diode 15 were connected to the individual circuits of the pair of secondary windings 11 and 12 of the input transformer 7, but FIGS. As shown in the figure, the windings 11 and 12 may be a common winding. In the case of Figure 2, transistor 1
Since the transistor 4 is of the current drive type, the pin diode 15 is connected in a step-up manner, and in the case of FIG. 3, the transistor 14 is of the voltage drive type.
Since it is a FET, the impedance of the secondary winding 11 is high, so the pin diode 15 is connected in a step-down manner.
また、ピンダイオード１５は上記各実施例のよ
うに入力トランス７の２次側巻線１２に限られ
ず、第４図のように１次側巻線８に接続されてい
ても同様の効果を奏することができる。もつと
も、この場合、バラクタ６のバイアス用抵抗１
９，２０と、直流遮断用コンデンサ２１を入力同
調回路１８に付加することが要求される。 Further, the pin diode 15 is not limited to the secondary winding 12 of the input transformer 7 as in each of the above embodiments, but the same effect can be achieved even if it is connected to the primary winding 8 as shown in FIG. be able to. However, in this case, the bias resistor 1 of the varactor 6
9, 20 and a DC cutoff capacitor 21 are required to be added to the input tuning circuit 18.
この考案は以上詳述したように、入力トランス
の１次側もしくは２次側巻線の中間タツプにピン
ダイオードを接続し、入力信号に比例してこのダ
イオードへの順方向電流を増減させることによ
り、強電界入力信号の受信時における信号歪や混
変調などを防止できるバラクタ同調式AMラジオ
受信機を提供することができる。 As detailed above, this idea connects a pin diode to the intermediate tap of the primary or secondary winding of the input transformer, and increases or decreases the forward current to this diode in proportion to the input signal. Therefore, it is possible to provide a varactor-tuned AM radio receiver that can prevent signal distortion and cross-modulation when receiving strong electric field input signals.
第１図はこの考案に係るラジオ受信機の一例を
示すバラクタ入力同調回路部の電気結線図、第２
図ないし第４図は他のそれぞれ異なる例を示す要
部の電気結線図である。
１……アンテナ等価回路、６……バラクタ、７
……入力トランス、８……１次側巻線、１２……
２次側巻線、１５……ピンダイオード、１７……
自動利得制御（AGC）用増幅器。
Fig. 1 is an electrical wiring diagram of a varactor input tuning circuit section showing an example of a radio receiver according to this invention;
4 through 4 are electrical wiring diagrams of main parts showing other different examples. 1...Antenna equivalent circuit, 6...Varactor, 7
...Input transformer, 8...Primary winding, 12...
Secondary winding, 15...Pin diode, 17...
Amplifier for automatic gain control (AGC).
Claims (1)
アンテナに結合されるバラクタ同調式AM受信機
において、上記入力トランスの１次側もしくは２
次側巻線の中間タツプにピンダイオードを接続す
るとともに、入力信号に比例して上記ピンダイオ
ードに電流を流すための自動利得制御用増幅器を
上記ピンダイオードの回路に接続したことを特徴
とするバラクタ同調式AMラジオ受信機。 In a varactor-tuned AM receiver in which the primary winding of the input transformer is coupled to the antenna via a varactor, the primary winding of the input transformer or
A varactor characterized in that a pin diode is connected to the intermediate tap of the next winding, and an automatic gain control amplifier is connected to the circuit of the pin diode for causing current to flow through the pin diode in proportion to the input signal. Tunable AM radio receiver.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1770680U JPS62280Y2 (en) | 1980-02-13 | 1980-02-13 |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1770680U JPS62280Y2 (en) | 1980-02-13 | 1980-02-13 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS56119335U JPS56119335U (en) | 1981-09-11 |
| JPS62280Y2 true JPS62280Y2 (en) | 1987-01-07 |
Family
ID=29614046
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1770680U Expired JPS62280Y2 (en) | 1980-02-13 | 1980-02-13 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS62280Y2 (en) |
-
1980
- 1980-02-13 JP JP1770680U patent/JPS62280Y2/ja not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS56119335U (en) | 1981-09-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4048598A (en) | Uhf tuning circuit utilizing a varactor diode | |
| US4805232A (en) | Ferrite-core antenna | |
| JPH0117855Y2 (en) | ||
| US4403347A (en) | Antenna tuning circuit for AM radio receiver | |
| US5307026A (en) | Variable gain RF amplifier with linear gain control | |
| JPS62280Y2 (en) | ||
| US4048578A (en) | R.f. amplifier circuit | |
| US3579113A (en) | Antenna coupling circuit | |
| JPS6324656Y2 (en) | ||
| JPS6347089Y2 (en) | ||
| JPH0724826Y2 (en) | Tuner device | |
| US4314252A (en) | Preamplifier for ADF loop antenna | |
| JPH066633Y2 (en) | Electronic tuning tuner | |
| JPS6127228Y2 (en) | ||
| JPS6328524B2 (en) | ||
| KR810000064B1 (en) | Radio receiver blanker gate | |
| JPS6127218Y2 (en) | ||
| JPS6216025Y2 (en) | ||
| JPH0510843B2 (en) | ||
| JPS6127217Y2 (en) | ||
| JPH0129868Y2 (en) | ||
| JPS6133725Y2 (en) | ||
| JPH0139003Y2 (en) | ||
| JPH0510419Y2 (en) | ||
| JPS6314490Y2 (en) |