JPH0467378B2 - - Google Patents
Info
- Publication number
- JPH0467378B2 JPH0467378B2 JP6843384A JP6843384A JPH0467378B2 JP H0467378 B2 JPH0467378 B2 JP H0467378B2 JP 6843384 A JP6843384 A JP 6843384A JP 6843384 A JP6843384 A JP 6843384A JP H0467378 B2 JPH0467378 B2 JP H0467378B2
- Authority
- JP
- Japan
- Prior art keywords
- transformer
- receiver
- loop antenna
- frequency
- circuit
- 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
- 239000003990 capacitor Substances 0.000 claims description 9
- 230000035945 sensitivity Effects 0.000 description 4
- 238000010586 diagram Methods 0.000 description 3
- 230000005855 radiation Effects 0.000 description 3
- 230000002902 bimodal effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005669 field effect Effects 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
Landscapes
- Input Circuits Of Receivers And Coupling Of Receivers And Audio Equipment (AREA)
Description
【発明の詳細な説明】
産業上の利用分野
本発明は、AMオールバンド受信機、特にその
アンテナ入力回路に関するものである。DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an AM all-band receiver, and in particular to an antenna input circuit thereof.
従来例の構成とその問題点
従来のAM受信機のループアンテナによるアン
テナ入力回路について第１図を用いて説明する。
一般に輻射感度を得るためにループアンテナ１が
使用される。特にループアンテナ１の場合は、そ
の動作インピーダンスが低いため、マツチングの
為に変成器２を使用するとともに、変成器２の２
次側に可変コンデンサ３を使用して受信周波数に
同調させ、その共振特性を利用してマツチングを
取り、混合器あるいは増幅器に接続されている。Conventional configuration and its problems An antenna input circuit using a loop antenna of a conventional AM receiver will be explained with reference to FIG.
Generally, a loop antenna 1 is used to obtain radiation sensitivity. In particular, in the case of loop antenna 1, since its operating impedance is low, transformer 2 is used for matching, and transformer 2's 2
A variable capacitor 3 is used on the next side to tune it to the reception frequency, and its resonance characteristics are used to perform matching, and it is connected to a mixer or amplifier.
しかしながらこの様な従来の構成では、可変コ
ンデンサ３の変化が対応出来ない時は極端に感度
特性が劣化する。例えば電子同調型受信機に於い
て、第１中間周波数を30数ＭHzに設定した場合、
受信周波数変化は150KHz〜30MHzで200倍に達す
るが、発振周波数変化が２倍程度の受信機の場
合、この受信周波数に追随する同調回路を構成す
ることが出来ないことがある。 However, in such a conventional configuration, when changes in the variable capacitor 3 cannot be accommodated, the sensitivity characteristics deteriorate extremely. For example, in an electronically tuned receiver, if the first intermediate frequency is set to 30-odd MHz,
The reception frequency change reaches 200 times from 150KHz to 30MHz, but in the case of a receiver where the oscillation frequency change is about twice, it may not be possible to construct a tuning circuit that follows this reception frequency.
発明の目的
本発明は上記従来の欠点を解消するもので、単
一バンドオールウエーブ受信機の輻射感度をもつ
アンテナ入力回路を有するAM受信機を提供する
ことを目的とする。OBJECTS OF THE INVENTION The present invention overcomes the above-mentioned conventional drawbacks and aims to provide an AM receiver having an antenna input circuit with the radiation sensitivity of a single-band all-wave receiver.
発明の構成
上記目的を達成するため、本発明のAM受信機
は、ループアンテナと、インピーダンスマツチン
グ用の変成器と、前記ループアンテナと前記変成
器の１次側コイルとの間に挿入されたコンデンサ
とを備え、前記コンデンサと１次側コイルとによ
る共振周波数をLW周波帯と中心付近に設定し、
前記変成器の２次側コイルと回路の漂遊容量とに
よる共振周波数をMW周波帯の中心付近に設定し
た構成としたものである。Composition of the Invention In order to achieve the above object, the AM receiver of the present invention includes a loop antenna, a transformer for impedance matching, and an AM receiver inserted between the loop antenna and the primary coil of the transformer. a capacitor, the resonance frequency of the capacitor and the primary coil is set near the center of the LW frequency band,
The configuration is such that the resonance frequency due to the secondary coil of the transformer and the stray capacitance of the circuit is set near the center of the MW frequency band.
実施例の説明
以下、本発明の一実施例について、図面に基づ
いて説明する。DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.
第２図は本発明の一実施例におけるAM受信機
の回路図で、１はループアンテナ、４はコンデン
サ、５は変成器、６は電界効果トランジスタ（以
下「FET」と記す）、７は抵抗である。 FIG. 2 is a circuit diagram of an AM receiver according to an embodiment of the present invention, in which 1 is a loop antenna, 4 is a capacitor, 5 is a transformer, 6 is a field effect transistor (hereinafter referred to as "FET"), and 7 is a resistor. It is.
ループアンテナ１に誘起した高周波電流は、シ
リーズに接続されたコンデンサ４を通して変成器
５に供給される。ここでコンデンサ４と変成器５
の１次側のコイル５ａとによる共振周波数をLW
バンドの受信周波数の中に設定する。変成器５の
２次側は増幅器に接続されている。この時、２次
側のコイル５ｂとこれに接続される回路の漂遊容
量Coとの共振点をMW受信帯の中に設定し、
FET６と抵抗７とで構成される増幅器に接続す
る。 The high frequency current induced in the loop antenna 1 is supplied to the transformer 5 through the capacitor 4 connected in series. Here capacitor 4 and transformer 5
The resonance frequency due to the primary side coil 5a of LW
Set within the receiving frequency of the band. The secondary side of transformer 5 is connected to an amplifier. At this time, the resonance point between the secondary coil 5b and the stray capacitance Co of the circuit connected to it is set within the MW reception band,
Connect to an amplifier consisting of FET 6 and resistor 7.
上記構成のアンテナ入力回路は、一種の双峰特
性をもつ複共振回路を構成する。このように極め
て簡単な回路により、低いインピーダンスのルー
プアンテナ１に誘起した高周波電力を、広い帯域
にわたつて取り出すことができる。 The antenna input circuit configured as described above constitutes a multi-resonant circuit having a kind of bimodal characteristic. With such an extremely simple circuit, the high frequency power induced in the low impedance loop antenna 1 can be extracted over a wide band.
発明の効果
以上説明したように本発明によれば、従来の同
調型アンテナ入力回路を使用出来ない、広帯域オ
ールウエーブ受信機においても、簡単な回路によ
つて、LW−MWの周波帯における輻射入力に対
する感度を充分に得ることができる。Effects of the Invention As explained above, according to the present invention, even in a wideband all-wave receiver in which a conventional tunable antenna input circuit cannot be used, radiation input in the LW-MW frequency band can be achieved using a simple circuit. It is possible to obtain sufficient sensitivity to
第１図は従来のAM受信機における同調型入力
回路の回路図、第２図は本発明の一実施例におけ
るAM受信機の要部の回路図である。
５ａ……１次側コイル、５ｂ……２次側コイ
ル、Co……漂遊容量。
FIG. 1 is a circuit diagram of a tunable input circuit in a conventional AM receiver, and FIG. 2 is a circuit diagram of essential parts of an AM receiver in an embodiment of the present invention. 5a...Primary side coil, 5b...Secondary side coil, Co...Stray capacitance.
Claims (1)
グ用の変成器と、前記ループアンテナと前記変成
器の１次側コイルとの間に挿入されたコンデンサ
とを備え、前記コンデンサと１次側コイルとによ
る共振周波数をLW周波帯の中心付近に設定し、
前記変成器の２次側コイルと回路の漂遊容量とに
よる共振周波数をMW周波帯の中心付近に設定し
たAM受信機。1. A loop antenna, a transformer for impedance matching, and a capacitor inserted between the loop antenna and the primary coil of the transformer, and a resonant frequency caused by the capacitor and the primary coil. Set near the center of the LW frequency band,
An AM receiver in which the resonance frequency due to the secondary coil of the transformer and the stray capacitance of the circuit is set near the center of the MW frequency band.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59068433A JPS60212036A (en) | 1984-04-05 | 1984-04-05 | AM receiver |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP59068433A JPS60212036A (en) | 1984-04-05 | 1984-04-05 | AM receiver |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS60212036A JPS60212036A (en) | 1985-10-24 |
| JPH0467378B2 true JPH0467378B2 (en) | 1992-10-28 |
Family
ID=13373561
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP59068433A Granted JPS60212036A (en) | 1984-04-05 | 1984-04-05 | AM receiver |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS60212036A (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109188061B (en) * | 2018-07-19 | 2020-12-08 | 上海思源弘瑞自动化有限公司 | Signal processing system and method |
-
1984
- 1984-04-05 JP JP59068433A patent/JPS60212036A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS60212036A (en) | 1985-10-24 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US4263676A (en) | RF amplifying system having image rejection | |
| US3942120A (en) | SWD FM receiver circuit | |
| JPH0467378B2 (en) | ||
| JPS6043696B2 (en) | VHF tuner interstage tuning coupling circuit | |
| JPS636906Y2 (en) | ||
| JPS6127228Y2 (en) | ||
| US2995652A (en) | Single transistor reflex circuit | |
| JPH048675Y2 (en) | ||
| JPS6241443Y2 (en) | ||
| JPS6017933Y2 (en) | Base grounded transistor amplifier circuit | |
| JPS6219006Y2 (en) | ||
| JPS6148239A (en) | Am receiver | |
| JPH0352020Y2 (en) | ||
| JPS58988Y2 (en) | radio receiver | |
| JPH0134442Y2 (en) | ||
| EP1154559A2 (en) | Oscillator | |
| SU77468A3 (en) | UHF receiver | |
| JPH0728743Y2 (en) | Local oscillator circuit of radio receiver | |
| JPH066633Y2 (en) | Electronic tuning tuner | |
| JPS60212037A (en) | Am receiver | |
| US2996614A (en) | Stabilized transistor oscillator circuit | |
| JPH0110014Y2 (en) | ||
| JP2572477Y2 (en) | Receiver tuning circuit | |
| JPH0314843Y2 (en) | ||
| JPH046274Y2 (en) |