JPS60136408A - High frequency signal switching device - Google Patents

High frequency signal switching device

Info

Publication number
JPS60136408A
JPS60136408A JP24414483A JP24414483A JPS60136408A JP S60136408 A JPS60136408 A JP S60136408A JP 24414483 A JP24414483 A JP 24414483A JP 24414483 A JP24414483 A JP 24414483A JP S60136408 A JPS60136408 A JP S60136408A
Authority
JP
Japan
Prior art keywords
frequency
signal
switching device
signal switching
antenna
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
Application number
JP24414483A
Other languages
Japanese (ja)
Inventor
Noboru Kawamoto
河本　登
Joji Nakamura
中村　穣治
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Panasonic Holdings Corp
Original Assignee
Matsushita Electric Industrial Co Ltd
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Matsushita Electric Industrial Co Ltd filed Critical Matsushita Electric Industrial Co Ltd
Priority to JP24414483A priority Critical patent/JPS60136408A/en
Publication of JPS60136408A publication Critical patent/JPS60136408A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03J—TUNING RESONANT CIRCUITS; SELECTING RESONANT CIRCUITS
    • H03J5/00—Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner
    • H03J5/24—Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner with a number of separate pretuned tuning circuits or separate tuning elements selectively brought into circuit, e.g. for waveband selection or for television channel selection
    • H03J5/242—Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner with a number of separate pretuned tuning circuits or separate tuning elements selectively brought into circuit, e.g. for waveband selection or for television channel selection used exclusively for band selection
    • H03J5/244—Discontinuous tuning; Selecting predetermined frequencies; Selecting frequency bands with or without continuous tuning in one or more of the bands, e.g. push-button tuning, turret tuner with a number of separate pretuned tuning circuits or separate tuning elements selectively brought into circuit, e.g. for waveband selection or for television channel selection used exclusively for band selection using electronic means

Landscapes

  • Filters And Equalizers (AREA)

Abstract

PURPOSE:To prevent leak of a UHF-modulated VTR reproduced signal to the antenna side by setting a high-pass filter for UHF to off-through type in an antenna switching circuit for VHF and UHF. CONSTITUTION:The high-pass filter and a low-pass filter connected in parallel are constituted by combining inductive and capacitive reactances as shown in the figure, and a switch means Q1 is connected in parallel with an inductive reactance L2 of the high-pass filter to constitute the antenna switching circuit of off-through type with respect to a UHF band. Though the VTR signal is reproduced with the UHF band by an RF modulator, the reproduced signal of the UHF band is much attenuated when the reactance L2 is short-circuited by the means Q1, and it is hardly leaked to an antenna signal input terminal. A varactor diode D2 is controlled to change characteristics of the low-pass filter, and the center frequency of attenuation is changed.

Description

【発明の詳細な説明】 （産業上の利用分野） 本発明は、アンテナ信号とＶＴＲ、ビデオディスク等の
再生信号とを切シ換える高周波信号切換装置に関する。DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a high frequency signal switching device that switches between an antenna signal and a reproduction signal of a VTR, video disc, etc.

（従来例の構成とその問題点） ＶＴＲ、ビデオディスク等の映像機器は、再生されたテ
レビ高周波信号がＴＶ受像機に接続され、テレビの空き
チャンネルを利用して再生される。又一般のテレビ高周
波信号も同時にこれらの映像機器に内蔵されたアンテナ
信号切換装置を介してテレビ受像機のアンテナ信号入力
に接続されている。(Structure of conventional example and its problems) In video equipment such as a VTR and a video disc, a reproduced television high frequency signal is connected to a TV receiver, and is reproduced using an empty channel on the television. Also, a general television high frequency signal is also connected to the antenna signal input of the television receiver via an antenna signal switching device built into these video devices.

第１図に代表的な接続例を示す。ＶＴＲ，ビデオディス
ク２に内蔵されているアンテナ信号切換装置３は、ＶＴ
Ｒ１ビデオディスク２の再生機能動作をしていないとき
は、アンテナ信号は、ＶＴＲ１ビデオディスク２の入力
端子に印加され、分配器を通して、又はそのまま高周波
信号出力端子へ出力され、ＴＶ受像機５へ印加される。Figure 1 shows a typical connection example. The antenna signal switching device 3 built in the VTR, video disc 2
When the playback function of the R1 video disc 2 is not in operation, the antenna signal is applied to the input terminal of the VTR 1 video disc 2, passed through the distributor or output as is to the high frequency signal output terminal, and applied to the TV receiver 5. be done.

次にＶＴＲ，ビデオディスクが再生される場合は、ＲＦ
モジュレータ４によυ高周波テレビ信号に変換された信
号がアンテナ信号切換装置３を介して高周波出力端子へ
出力され、ＴＶ受像機５へ印加される。このときＶＴＲ
、ビデオディスクのアンテナ信号切換装置３の信号入力
端子へのＲＦモノユレータ４からの信号の漏洩電圧に対
しては各国法規制が適用され、アンテナ信号切換装置の
入出力端子間に、信号アイソレーションを確保すること
が必要となる。これらの機器は、日本あるいは米国等で
使用する場合には、■Ｆ帯で再生される場合が多い。又
欧州地域はＵ）ＩＦ帯で再生される場合が多い。ビデオ
、ビデオディスクのアンテナ信号切換はダイオード又は
トランジスタによる切換機能によりこれらを制御してい
るのが一般的であ、９、ＶＨＦ帯を利用したアンテナ信
号切換装置には、最近オフスルー型信号切換装置すなわ
ちビデオ、ビデオディスクを使用しない場合、機器の電
源をすべて切ってもアンテナ信号がＴＶ受像機へ入力さ
れ、ビデオ、ビデオディスクを使用する場合、再生テレ
ビ信号をＴＶ受像機へ印加し、かつアンテナ入力端子へ
の漏洩信号を遮断する信号切換回路を採用し消費電力の
低減化がはかられている。一方ＵＨＦ帯は、アンテナ信
号切換装置に、高周波トランジスタによる増幅回路を設
けて、アンテナ入力信号の出力端子への伝送と増幅回路
の逆方向伝送特性によるアイソレーション効果により、
再生時のアンテナ入力端子へのＲＦモジュレータからの
信号漏洩を防いでいるのが一般的である。この場合、ビ
デオ、ビデオディ２りが再生機能をしていない時も、常
にアンテナ信号切換装置には増幅用トランジスタの動作
用の電力が必要となｆｉ、ＶＨＦ帯で利用されているよ
うなオフスルー機能ではなく、有効的でない。Next, when a VTR or video disc is played, the RF
The signal converted into the high frequency television signal by the modulator 4 is output to the high frequency output terminal via the antenna signal switching device 3 and applied to the TV receiver 5. At this time, the VTR
The laws and regulations of each country apply to the leakage voltage of the signal from the RF monoulator 4 to the signal input terminal of the antenna signal switching device 3 of the video disc, and signal isolation is required between the input and output terminals of the antenna signal switching device. It is necessary to secure it. When these devices are used in Japan or the United States, they are often played back in the ■F band. Also, in Europe, music is often played in the U)IF band. Antenna signal switching for videos and video disks is generally controlled by switching functions using diodes or transistors. 9. Recently, off-through type signal switching devices or When not using a video or video disc, the antenna signal is input to the TV receiver even if all power is turned off. When using a video or video disc, the reproduced TV signal is applied to the TV receiver and the antenna input A signal switching circuit that blocks signals leaking to the terminals is used to reduce power consumption. On the other hand, in the UHF band, an amplifier circuit using a high-frequency transistor is installed in the antenna signal switching device, and the transmission of the antenna input signal to the output terminal and the isolation effect due to the reverse transmission characteristics of the amplifier circuit are performed.
It is common to prevent signal leakage from the RF modulator to the antenna input terminal during playback. In this case, the antenna signal switching device always requires power to operate the amplification transistor even when the video or video receiver is not in playback mode. Not functional, not effective.

（発明の目的） 本発明は斯かる事情に鑑みてなされたもので、ＵＨＦ帯
にも利用でき、かつビデオ、ビデオディスクが再生機能
しない場合オフスルー機能を有するアンテナ信号切換装
置を提供しようとするものである。(Object of the Invention) The present invention has been made in view of the above circumstances, and aims to provide an antenna signal switching device that can also be used in the UHF band and has an off-through function when a video or video disc does not play back. It is.

（発明の構成） 本発明のテレビ高周波信号切換装置は、容量性リアクタ
ンスと誘導性リアクタンスからなる第１の低域Ｆ波器と
、誘導性リアクタンスと容量性リアクタンスからなる第
２の高域Ｆ波器を信号入力端子と出力端子との間に並列
接続し、前記第２のＦ波器の誘導性リアクタンスと並列
にトランジスタ又はスイッチングダイオードを接続し、
トランジスタまたはスイッチングダイオードを導通制御
して信号入出力端子間を遮断又は導通制御するも（５） のであシ、前記第１の低域ろ波器の容量性リアクタンス
を可変容量ダイオードで構成して遮断周波数を可変にし
てもよく、また第１の低域Ｆ波器と第２の高域沖波器の
構成を２段以上縦続接続してもよい。(Structure of the Invention) The television high frequency signal switching device of the present invention includes a first low-frequency F-wave device consisting of a capacitive reactance and an inductive reactance, and a second high-frequency F-wave device consisting of an inductive reactance and a capacitive reactance. a transistor or a switching diode is connected in parallel with the inductive reactance of the second F-wave device,
Although the conduction of a transistor or a switching diode is controlled to cut off or control the continuity between the signal input and output terminals, (5) it is also possible to block the capacitive reactance of the first low-pass filter by configuring it with a variable capacitance diode. The frequency may be made variable, and the first low-frequency F wave device and the second high-frequency Okinawa wave device may be connected in cascade in two or more stages.

（実施例の説明） 第２図は本発明の一実施例を示す図で、アンテナ信号入
力よシ被電防止用インダクタンスＩ４枡し、容量性リア
クタンスからなるコンデンサｃ１及びＣ２と誘導性リア
クタンスからなるインダクタンスＬ２によシ高域沖波器
を構成し、さらに誘導性リアクタンスＬ３及びＬ４から
なるインダクタンスと容量性リアクタンスからなるコン
デンサＣ３よシなる低域Ｐ波器を構成しそれぞれのｐ波
器をアンテナ入力信号端子と出力端子の間に接続し、イ
ンダクタンスＬ２と並列にトランジスタＱを接続し、コ
レクタはＬ２の高電位側に、エミッタはアースに接続し
、ペース端子へは外部電源端子子Ｂより抵抗Ｒを介して
直流バイアスが印加出来るよう構成されている。一方Ｒ
Ｆモジュレータの高（６） 周波出力信号は切換装置の出力端子に接続されている。(Explanation of Embodiment) Fig. 2 is a diagram showing an embodiment of the present invention, in which an inductance I4 is connected to the antenna signal input, and the capacitors C1 and C2 are composed of capacitive reactances and inductive reactances. The inductance L2 constitutes a high frequency wave transducer, and the inductance composed of inductive reactances L3 and L4 and the capacitor C3 constitutes a low frequency P wave transducer, and each P wave transducer is input to the antenna. Connect between the signal terminal and the output terminal, connect the transistor Q in parallel with the inductance L2, the collector is connected to the high potential side of L2, the emitter is connected to the ground, and the resistor R is connected to the pace terminal from the external power terminal B. The structure is such that a DC bias can be applied through the . On the other hand, R
The high (6) frequency output signal of the F modulator is connected to the output terminal of the switching device.

本発明によれば、電源端子に直流バイアスが加えられな
い場合は、第５図の動作例の如く、”３　＋　”４　ｒ
　ｃ３による低域泥波器（ＬＰＦ）特性と、ＣＩ　＋”
２　ｙ”２による高域沖波器（ＨＰＦ）の合成された特
性として第５図（ｂ）に示す入出力伝送特性として、広
帯域の損失の少ない信号伝達が出来る。電源端子子Ｂよ
り正の直流バイアスを加えた場合Ｌ２ハトランジスタＱ
のコレクターエミッタ間が高周波的に低いインピーダン
ヌ成分と並列接続され第５図（ｃ）の破線に示す如（Ｈ
ＰＦ’が構成されなくなり、ＴＪ３　＋　”Ｊ４　＊　
ｃ３よりなるり、ＰＦの伝達特性との和となシ第５図（
ｄ）の如くの特性となる。特に第５図（ｃ）に示す交点
ｆ。なる周波数においては、ＬＰＦ、ＨＰＦの位相差が
１８０度異ｌ６ことを利用すれば第５図（ｄ）に示す通
１）ｆ。なる周波数においては信号成分は大きく減衰さ
せることができる。従ってｆ。なる周波数をＲＦモジュ
レータの出力周波数に選定すればアンテナ信号入力端子
にはモジュレータ出力成分は漏洩せず、又テレビ高周波
信号出力端子に出力信号として出力し、ＴＶ受像機へ信
号を印加することができる。このように電源をオフして
も信号を出力端子へ送り、電源をオンすることによりＲ
Ｆモジュレータの信号をアンテナ信号入力端子に漏洩さ
せることなく信号を切換えることができる。第３図にト
ランジスタの代わりにダイオードを用いた実施例を示す
。According to the present invention, when no DC bias is applied to the power supply terminal, "3 + "4 r
Low frequency mud filter (LPF) characteristics by c3 and CI +”
As the input/output transmission characteristics shown in Figure 5(b) as the combined characteristics of the high-frequency offshore wave filter (HPF) using 2y''2, wideband signal transmission with low loss is possible.Positive DC from power terminal B When applying bias, L2 transistor Q
The collector-emitter of the is connected in parallel with the impedance component, which is low in high frequency.
PF' is no longer configured and TJ3 + "J4 *
Figure 5 (
The characteristics are as shown in d). In particular, the intersection f shown in FIG. 5(c). At a frequency of Signal components can be greatly attenuated at frequencies such as Therefore f. If a frequency of . In this way, even if the power is turned off, the signal is sent to the output terminal, and when the power is turned on, the R
The signal can be switched without leaking the F modulator signal to the antenna signal input terminal. FIG. 3 shows an embodiment using diodes instead of transistors.

さらにＵＨＦ用アンテナ切換の場合、ＲＦモジ−レータ
の出力周波数が可変される機会が多いが、第４図に示す
如り、ＬＰＦのコンデンサＣ３の代わりに可変容量ダイ
オードを用いてＬＰＦの遮断周波数を可変し、第５図（
ｃ）の交錯する周波数ｆ。を可変することにより、ＲＦ
モジュレータの出力周波数に相当する周波数に任意に設
定することができる。又ＲＦモジュレｉりの周波数可変
用制御電圧と連動させることもできる。Furthermore, in the case of UHF antenna switching, the output frequency of the RF modulator is often varied, but as shown in Figure 4, a variable capacitance diode is used in place of the LPF capacitor C3 to adjust the cutoff frequency of the LPF. Figure 5 (
c) Intersecting frequency f. By varying the RF
It can be arbitrarily set to a frequency corresponding to the output frequency of the modulator. It can also be linked with the frequency variable control voltage of the RF modulator.

（発明の効果） 以上のように本発明によれば、簡単な回路構成で、ＵＨ
Ｆ帯にも利用できるオフスルー型アンテナ切換回路を実
現することができる。(Effects of the Invention) As described above, according to the present invention, UH
It is possible to realize an off-through type antenna switching circuit that can also be used in the F band.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は、テレビ受像機とビデオ又はビデオディスクの
テレビ高周波信号接続例を示す図、第２図〜第４図は、
本発明による高周波信号切換回路の実施例を示す図、 第５図は、アンテナ切換装置の動作例を示す図である。 １・・・アンテナ、２・・・ＶＴＲ又はビデオディスク
、３・・・アンテナ信号切換装置、４・・・ＲＦモジ−
レータ、５・・・テレビ受像機 （９） 第１図 第２図 ＋Ｂ（電源端子） 第３図 第４図 Ｃ＋　Ｃ２ ７〉テナ　テレビｉ！］局波 信号ｂ」ノフ ２ １ Ｌ３　Ｌ４ 冬　、１− 第５図 （ａ）　（ｂ） （ｃ）　（ｄ） ｆｏ　菖ＡＫＭＨｚ）　ｆｏ　ＦｌｆｌＡＴｈ（ＭＨｚ
）人　人 （ε可叉）FIG. 1 is a diagram showing an example of a television high frequency signal connection between a television receiver and a video or video disc, and FIGS. 2 to 4 are
FIG. 5 is a diagram showing an example of the operation of the antenna switching device. 1... Antenna, 2... VTR or video disc, 3... Antenna signal switching device, 4... RF module
Rator, 5...TV receiver (9) Fig. 1 Fig. 2 +B (power terminal) Fig. 3 Fig. 4 C+ C2 7〉Tena TV i! ] Local wave signal b'nofu 2 1 L3 L4 winter, 1- Fig. 5 (a) (b) (c) (d) fo AKMHz) fo FlflATh(MHz
) person person (εkasha)

Claims (4)

【特許請求の範囲】[Claims] （１）テレビ高周波信号切換装置において容量性リアク
タンスと誘導性リアクタンスからなる第１の低域Ｐ波器
と誘導性リアクタンスと容量性リアクタンスからなる第
２の高域沖波器を信号入力端子と出力端子との間に並列
接続し、前記第２の涙波器の誘導性リアクタンスと並列
に、ＮＰＮバイポーラトランジスタを、そのコレクタが
誘導性リアクタンスの高電位側に、エミッタをアース側
ニソれぞれ接続し、ペース端子に外部よシ直流バイアス
を加え、ペース直流バイアスの制御により信号入力端子
から出力端子への信号の遮断又は導通を制御することを
特徴とする高周波信号切換装置。(1) In a TV high-frequency signal switching device, a first low-frequency P-wave device consisting of a capacitive reactance and an inductive reactance and a second high-frequency O wave device consisting of an inductive reactance and a capacitive reactance are connected to a signal input terminal and an output terminal. and an NPN bipolar transistor in parallel with the inductive reactance of the second tear wave device, the collector of which is connected to the high potential side of the inductive reactance, and the emitter of which is connected to the ground side of the inductive reactance. A high-frequency signal switching device characterized in that an external DC bias is applied to the pace terminal, and by controlling the pace DC bias, blocking or conduction of the signal from the signal input terminal to the output terminal is controlled. （２）前記第２のろ波器の誘導性リアクタンスと並列に
高周波スイッチングダイオードを使用し、ダイオードの
アノード又はカソードの一方に外部よシ直流バイアスを
加え、直流バイアスの制御によシ信号入力端子から出力
端子への信号の遮断又は導通を制御することを特徴とす
る特許請求の範囲第（１）項記載の高周波信号切換装置
。(2) A high frequency switching diode is used in parallel with the inductive reactance of the second filter, an external DC bias is applied to one of the anode or cathode of the diode, and a signal input terminal is used to control the DC bias. The high-frequency signal switching device according to claim 1, wherein the high-frequency signal switching device controls blocking or conduction of a signal from the output terminal to the output terminal. （３）前記第１の低域済波器の容量性リアクタンスに可
変容量ダイオードを使用し、遮断周波数を可変容量ダイ
オードによシ可変としたことを特徴とする特許請求の範
囲第（１）項又は第（２）項記載の高周波信号切換装置
。(3) Claim (1) characterized in that a variable capacitance diode is used for the capacitive reactance of the first low-frequency wave generator, and the cut-off frequency is made variable by the variable capacitance diode. Or the high frequency signal switching device according to item (2). （４）前記第１の低域渥波器及び第２の高域涙波器の構
成を２段以上縦続接続したことを特徴とする特許請求の
範囲第（１）項、第（２）項、又は第（３）項記載の高
周波信号切換装置。(4) Claims (1) and (2) characterized in that the first low-frequency wave filter and the second high-frequency wave filter are connected in cascade in two or more stages. , or the high frequency signal switching device according to item (3).
JP24414483A 1983-12-26 1983-12-26 High frequency signal switching device Pending JPS60136408A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP24414483A JPS60136408A (en) 1983-12-26 1983-12-26 High frequency signal switching device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP24414483A JPS60136408A (en) 1983-12-26 1983-12-26 High frequency signal switching device

Publications (1)

Publication Number Publication Date
JPS60136408A true JPS60136408A (en) 1985-07-19

Family

ID=17114411

Family Applications (1)

Application Number Title Priority Date Filing Date
JP24414483A Pending JPS60136408A (en) 1983-12-26 1983-12-26 High frequency signal switching device

Country Status (1)

Country Link
JP (1) JPS60136408A (en)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6412610A (en) * 1987-07-06 1989-01-17 Hitachi Ltd Semiconductor integrated circuit
JPH0348463U (en) * 1989-09-14 1991-05-09
EP1026885A1 (en) * 1999-02-04 2000-08-09 Alps Electric Co., Ltd. TV-signal receiving tuner with reduced extraneous emission
EP1058384A2 (en) * 1999-06-03 2000-12-06 The Whitaker Corporation Circuit for dual band tuning
WO2002054591A1 (en) * 2000-12-28 2002-07-11 Matsushita Electric Industrial Co., Ltd. High frequency low-pass filter
EP1519483A2 (en) * 2003-09-24 2005-03-30 Seiko Epson Corporation Impedance circuit, and filter circuit, amplifier circuit, semiconductor integrated circuit, electronic component, and wireless communications device using the same

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
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JPH0348463U (en) * 1989-09-14 1991-05-09
EP1026885A1 (en) * 1999-02-04 2000-08-09 Alps Electric Co., Ltd. TV-signal receiving tuner with reduced extraneous emission
US6639630B2 (en) 1999-02-04 2003-10-28 Alps Electric Co., Ltd. TV-signal receiving tuner with reduced extraneous emission
EP1058384A2 (en) * 1999-06-03 2000-12-06 The Whitaker Corporation Circuit for dual band tuning
EP1058384A3 (en) * 1999-06-03 2002-10-30 The Whitaker Corporation Circuit for dual band tuning
WO2002054591A1 (en) * 2000-12-28 2002-07-11 Matsushita Electric Industrial Co., Ltd. High frequency low-pass filter
US6895228B2 (en) 2000-12-28 2005-05-17 Matsushita Electric Industrial Co., Ltd. High frequency low-pass filter
EP1519483A2 (en) * 2003-09-24 2005-03-30 Seiko Epson Corporation Impedance circuit, and filter circuit, amplifier circuit, semiconductor integrated circuit, electronic component, and wireless communications device using the same
EP1519483A3 (en) * 2003-09-24 2006-04-26 Seiko Epson Corporation Impedance circuit, and filter circuit, amplifier circuit, semiconductor integrated circuit, electronic component, and wireless communications device using the same
US7218185B2 (en) 2003-09-24 2007-05-15 Seiko Epson Corporation Impedance circuit, and filter circuit, amplifier circuit, semiconductor integrated circuit, electronic component, and wireless communications device using the same

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