JPH0722975A - Am radio receive - Google Patents
Am radio receiveInfo
- Publication number
- JPH0722975A JPH0722975A JP15957493A JP15957493A JPH0722975A JP H0722975 A JPH0722975 A JP H0722975A JP 15957493 A JP15957493 A JP 15957493A JP 15957493 A JP15957493 A JP 15957493A JP H0722975 A JPH0722975 A JP H0722975A
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- Prior art keywords
- circuit
- frequency
- signal
- broadcasting station
- station
- 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.)
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Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、混信の発生を抑えるＡ
Ｍラジオ受信機に関し、特に、特定周波数関係となる２
信号妨害を排除するＡＭラジオ受信機に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is intended to suppress the occurrence of interference.
Regarding the M radio receiver, in particular, there is a specific frequency relationship 2
It relates to an AM radio receiver that eliminates signal jamming.
【０００２】[0002]
【従来の技術】従来のＡＭラジオ受信機は図２の如く構
成されており、ＲＦ同調回路５２から発生する受信ＲＦ
信号のレベルが所定以上になった時、ＲＦＡＧＣ回路５
７及び減衰制御回路５８は動作を開始する。ＲＦＡＧＣ
回路５７はＡＧＣトランジスタ６１のベースに印加され
ているベース電圧を低下させて、ＲＦ増幅器５１のＦＥ
Ｔ６２のドレインに供給される電流を制限する。また、
減衰制御回路５８は減衰回路５９に電圧を印加すること
によって、減衰回路５９内のＰＩＮダイオードを“Ｏ
Ｎ”させてアンテナを介した受信ＲＦ信号の一部をアー
スに流し、ＲＦ増幅器５１のＦＥＴ６２のゲートに印加
される受信ＲＦ信号のレベルを制限する。このように、
受信ＲＦ信号のレベルが所定以上にならないようにして
いた。2. Description of the Related Art A conventional AM radio receiver is constructed as shown in FIG.
When the signal level exceeds a predetermined level, the RFAGC circuit 5
7 and the damping control circuit 58 start operation. RFAGC
The circuit 57 lowers the base voltage applied to the base of the AGC transistor 61 to allow the FE of the RF amplifier 51 to operate.
Limit the current supplied to the drain of T62. Also,
The attenuation control circuit 58 applies a voltage to the attenuation circuit 59 to turn the PIN diode in the attenuation circuit 59 to “O”.
N "to allow a part of the RF signal received via the antenna to flow to the ground, thereby limiting the level of the RF signal received applied to the gate of the FET 62 of the RF amplifier 51.
The level of the received RF signal is prevented from exceeding a predetermined level.
【０００３】[0003]
【発明が解決しようとする課題】しかしながら、図２の
ＡＭラジオ受信機において、ＦＥＴ６１に受信ＲＦ信号
が印加された場合、ＦＥＴは非線形素子であり、その２
乗特性から高調波が発生する。即ち、ドレインに流れる
電流をＩD、飽和ドレイン電流をＩDDS、ゲート・ソース
間電圧をＶGS、ピンチオフ電圧をＶPとすると、ＦＥＴ
のドレイン電流はHowever, in the AM radio receiver of FIG. 2, when the reception RF signal is applied to the FET 61, the FET is a non-linear element, and
Harmonics are generated due to the power characteristics. That is, if the drain current is I D , the saturated drain current is I DDS , the gate-source voltage is V GS , and the pinch-off voltage is V P , the FET
Drain current of
【０００４】[0004]
【数１】 [Equation 1]
【０００５】と表わされる。ここで、ＦＥＴのゲートに
２つの信号ＶGS＝ｍ1ｓinｗ1ｔ＋ｍ 2ｓinｗ2ｔ（ｗ1，
ｗ2はそれぞれ２つの信号の角周波数）が印加されるとIs expressed as Here, in the gate of FET
Two signals VGS= M1sinw1t + m 2sinw2t (w1，
w2Are each applied the angular frequency of two signals)
【０００６】[0006]
【数２】 [Equation 2]
【０００７】となり、ＦＥＴからｗ1，ｗ2，２ｗ1，２
ｗ2，ｗ1＋ｗ2，ｗ1−ｗ2の高調波が発生する。即ち、
周波数ｆ1，ｆ2，２ｆ1，２ｆ2，ｆ1＋ｆ2，ｆ1−ｆ2の
信号が発生する。例えば、希望局周波数をｆ2、他の局
をｆ1（＝１／２×ｆ2）とすると、ｆ1の２倍の高調波
は周波数がｆ2となるので２ｆ1の高調波はＲＦ同調回路
によって遮断されず、ＭＩＸ段・ＩＦ段を通過し検波さ
れる。よって、ｆ1の周波数に放送局が存在する場合、
ＡＭラジオ受信機は混信を発生する。また、希望放送局
をｆ2、他の局をｆ1（＝２×ｆ2）とすると、ｆ1のｆ1
−ｆ2の高調波がｆ2となり、上述同様に混信が発生す
る。From the FET, w 1 , w 2 , 2w 1 , 2
Harmonics of w 2 , w 1 + w 2 , and w 1 -w 2 are generated. That is,
Frequency f 1, f 2, 2f 1 , 2f 2, f 1 + f 2, the signal of f 1 -f 2 is generated. For example, assuming that the desired station frequency is f 2 and the other stations are f 1 (= 1/2 × f 2 ), the frequency of a double harmonic of f 1 is f 2 , so the harmonic of 2f 1 is RF. It is not blocked by the tuning circuit, but passes through the MIX and IF stages and is detected. Therefore, if there is a broadcasting station at the frequency of f 1 ,
AM radio receivers generate interference. If the desired broadcasting station is f 2 and the other stations are f 1 (= 2 × f 2 ), f 1 of f 1
The harmonic of -f 2 becomes f 2 , and interference occurs as described above.
【０００８】上記の２信号妨害による混信を抑制する
為、図２のＡＭラジオ受信機ではＡＧＣ感度を常時上げ
ていたが、前記２信号妨害を発生する局以外のレベルが
大である周波数信号が印加された場合、ＦＥＴから高調
波が発生せず妨害が発生しないが、感度抑圧が発生し希
望放送局の感度が低く抑えられるという問題があった。In order to suppress the interference due to the above-mentioned two-signal interference, the AM radio receiver shown in FIG. 2 has always raised the AGC sensitivity. However, a frequency signal whose level is large except for the station which generates the two-signal interference is used. When applied, no harmonics are generated from the FET and no interference occurs, but there is a problem that sensitivity suppression occurs and the sensitivity of the desired broadcasting station is suppressed to a low level.
【０００９】[0009]
【課題を解決するための手段】本発明は上述の点を鑑み
成されたものであり、ＡＧＣ回路を備えたＡＭ受信機に
おいて、希望放送局の受信後前記希望放送局の２倍また
は１／２倍の少なくとも一方の周波数をもつ局を受信さ
せる手段と、前記局の電界強度が所定レベルであるか否
か検出する手段と、前記電界強度が所定レベル以上であ
る時ＡＧＣ回路の感度を上げると共に広帯域ＲＦ信号が
混合回路に印加されるように動作させる手段とを備えた
ことを特徴とする。SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and in an AM receiver having an AGC circuit, after receiving a desired broadcasting station, it is twice or 1 / th of the desired broadcasting station. Means for receiving a station having at least one frequency doubled, means for detecting whether or not the electric field strength of the station is at a predetermined level, and increasing the sensitivity of the AGC circuit when the electric field strength is at or above the predetermined level. And means for operating the broadband RF signal to be applied to the mixing circuit.
【００１０】また、希望放送局受信後前記希望放送局の
１／２倍及び２倍の周波数をもつ妨害局を受信させる手
段とを備えたことを特徴とする。Further, it is characterized in that it further comprises means for receiving an interfering station having a frequency which is 1/2 times or twice that of the desired broadcasting station after receiving the desired broadcasting station.
【００１１】[0011]
【作用】本発明に依れば、ＡＭラジオ受信機が希望の放
送局を受信した後、希望放送局周波数の２倍及び１／２
倍の周波数をもつ放送局を受信し各々の放送局の電界強
度を検出し所定レベル以上であるか否か判別する。電界
強度が所定以上のレベルであると判断された時、ＲＦ狭
帯域信号からＲＦ広帯域信号が混合回路に印加されるよ
うにすると共に、ＡＧＣ回路の感度を上げる。その後、
ＡＭラジオ受信機は希望放送局を受信し通常動作とな
る。According to the present invention, after the AM radio receiver receives a desired broadcasting station, it is twice and 1/2 of the desired broadcasting station frequency.
A broadcasting station having a frequency doubled is received, and the electric field strength of each broadcasting station is detected to determine whether or not the level is equal to or higher than a predetermined level. When it is determined that the electric field strength is at a level equal to or higher than a predetermined level, the RF wideband signal from the RF narrowband signal is applied to the mixing circuit, and the sensitivity of the AGC circuit is increased. afterwards,
The AM radio receiver receives the desired broadcasting station and operates normally.
【００１２】[0012]
【実施例】図１は本発明の一実施例を示す図である。１
はアンテナ、２は受信ＲＦ信号を減衰させる減衰回路、
３は受信ＲＦ信号を増幅するＲＦ増幅回路、４は受信Ｒ
Ｆ信号を同調するＲＦ同調回路、５は広帯域増幅器、６
はＲＦ同調回路４又は広帯域増幅器５の出力を選択する
切換回路、７はＩＦ信号を発生する混合器、８はＩＦ信
号を増幅するＩＦアンプ、９はＩＦ信号を検波する検波
器、４５は局発信号を発生するＯＳＣ、１０はＯＳＣ４
５を制御するＰＬＬ回路、１１は放送局の電界強度を検
出するＳメータ回路、１２はコントローラ、１３は抵抗
３４の一端から発生する出力信号を増幅する第１増幅回
路、１４は第１増幅回路から発生する信号のレベルを検
出する第１レベル検出回路、１５は切換回路６から発生
する信号を増幅する第２増幅回路、１６は第２増幅回路
から発生する信号のレベルを検出する第２レベル検出回
路、１７はＡＧＣ回路を発生するＲＦＡＧＣ回路、１８
は減衰回路の減衰量を制御する減衰制御回路であり、１
９及び２０はベースにＡＧＣ信号が印加されるＡＧＣト
ランジスタである。FIG. 1 is a diagram showing an embodiment of the present invention. 1
Is an antenna, 2 is an attenuation circuit for attenuating a received RF signal,
3 is an RF amplifier circuit for amplifying a received RF signal, 4 is a receiving R
RF tuning circuit for tuning the F signal, 5 a wide band amplifier, 6
Is a switching circuit for selecting the output of the RF tuning circuit 4 or the wide band amplifier 5, 7 is a mixer for generating an IF signal, 8 is an IF amplifier for amplifying the IF signal, 9 is a detector for detecting the IF signal, and 45 is a station. OSC that generates a signal to emit 10 is OSC4
5, a PLL circuit for controlling 5, an S meter circuit for detecting the electric field strength of the broadcasting station, a controller 12, a first amplifier circuit 13 for amplifying an output signal generated from one end of the resistor 34, and a first amplifier circuit 14 A first level detection circuit for detecting the level of the signal generated from the second amplification circuit, a second amplification circuit 15 for amplifying the signal generated by the switching circuit 6, and a second level 16 for detecting the level of the signal generated by the second amplification circuit. A detection circuit, 17 is an RF AGC circuit for generating an AGC circuit, 18
Is an attenuation control circuit that controls the amount of attenuation of the attenuation circuit.
Reference numerals 9 and 20 are AGC transistors to which the AGC signal is applied.
【００１３】また、図１において、減衰回路２は、直列
接続されたコンデンサー２１及びＰＩＮダイオード２３
と、カソードがコンデンサー２１とＰＩＮダイオード２
３との接続点に接続されるＰＩＮダイオード２２とから
成る。ＲＦ増幅回路３は、ゲートに受信ＲＦ信号が印加
されるＦＥＴ３１によって構成される。ＲＦ同調回路４
は、トランジスタ１９のコレクタに接続されるコイル４
１と、コイル４１とＲＣ並列回路を成しているコンデン
サー４３及びバリキャップコンデンサー４２とから成
る。また、広帯域増幅器５は、ＲＦ増幅器３と兼用とな
るＦＥＴ３１と、ＦＥＴ３１のドレインにＡＧＣトラン
ジスタ２０を介して接続される抵抗及びコイルとから成
る。Further, in FIG. 1, the attenuation circuit 2 includes a capacitor 21 and a PIN diode 23 which are connected in series.
And the cathode is condenser 21 and PIN diode 2
3 and a PIN diode 22 connected to the connection point. The RF amplification circuit 3 is composed of a FET 31 whose gate receives the received RF signal. RF tuning circuit 4
Is a coil 4 connected to the collector of the transistor 19
1 and a coil 43 and a capacitor 43 and a varicap capacitor 42 that form an RC parallel circuit. The broadband amplifier 5 is composed of a FET 31 that also serves as the RF amplifier 3, and a resistor and a coil that are connected to the drain of the FET 31 via the AGC transistor 20.
【００１４】次に図１のＡＭラジオ受信機の動作を図３
のフローチャートを参照して説明する。図１において、
Ｓ２における初期条件として切換回路６はＲＦ同調回路
の出力信号を発生するようにコントローラ１２によって
選択され、第１及び第２増幅回路の増幅率は第１の増幅
率と成されている。アンテナ１に入力された受信ＲＦ信
号は、ＲＦ増幅回路３で増幅され、ＲＦ同調回路４で周
波数選択され、混合回路７において、ＯＳＣ４５の局発
信号と混合され、所定のＩＦ信号に変換される。そし
て、ＯＳＣ４５の局発信号の周波数を可変すると同時
に、ＲＦ同調回路４の同調周波数を可変することによっ
て選局が行われる。Next, the operation of the AM radio receiver shown in FIG. 1 will be described with reference to FIG.
This will be described with reference to the flowchart in FIG. In FIG.
As an initial condition in S2, the switching circuit 6 is selected by the controller 12 to generate the output signal of the RF tuning circuit, and the amplification factors of the first and second amplification circuits are set to the first amplification factor. The received RF signal input to the antenna 1 is amplified by the RF amplification circuit 3, frequency-selected by the RF tuning circuit 4, mixed by the mixing circuit 7 with the local oscillation signal of the OSC 45, and converted into a predetermined IF signal. . Then, tuning is performed by changing the frequency of the local oscillation signal of the OSC 45 and, at the same time, changing the tuning frequency of the RF tuning circuit 4.
【００１５】Ｓ３において、希望放送局が受信される。
希望放送局の周波数をｆDとする。Ｓ４において、コン
トローラ１２はＰＬＬ回路１０を制御して、ＲＦ同調回
路４の同調周波数及びＯＳＣ４５から発生する局部発振
周波数を可変し、希望放送局の２倍の周波数、２×ｆD
の受信状態にする。この状態のままＳメータ回路１１に
おいて、ＩＦアンプ８から発生するＩＦ信号を整流する
ことにより、周波数２×ｆDの放送局の電界強度を検出
する。Ｓメータ回路１１から発生した電界強度値はコン
トローラ１２において所定レベルＡより大きいか否かを
判別される。前記電界強度値が所定レベルより小さい
時、Ｓ５に移る。At S3, the desired broadcast station is received.
Let f D be the frequency of the desired broadcasting station. In S4, the controller 12 controls the PLL circuit 10 to vary the tuning frequency of the RF tuning circuit 4 and the local oscillation frequency generated from the OSC 45, and double the frequency of the desired broadcasting station, 2 × f D.
To receive. In this state, the S meter circuit 11 rectifies the IF signal generated from the IF amplifier 8 to detect the electric field strength of the broadcasting station having the frequency 2 × f D. The controller 12 determines whether or not the electric field strength value generated from the S meter circuit 11 is larger than a predetermined level A. When the electric field strength value is smaller than the predetermined level, the process proceeds to S5.
【００１６】また、コントローラ１２において、ＰＬＬ
回路１０が制御される前に、周波数２×ｆDが受信バン
ド内に存在しない場合もＳ４に移り、存在する場合、上
述の動作が行われる。Ｓ５に移り、Ｓ４と同様にコント
ローラ１２はＰＬＬ回路１０を制御して希望放送局周波
数の１／２倍・１／２×ｆDの受信状態とする時、コン
トローラ１２において、周波数１／２×ｆDが受信バン
ド内に存在するか判別する。受信バンド内に有る時、受
信ＲＦ信号が１／２×ｆDの周波数となるように、ＰＬ
Ｌ回路１０が制御される。この状態でＳメータ回路１１
は、周波数１／２×ｆDの放送局の電界強度を検出す
る。コントローラ１２において、検出した電界強度が所
定レベルＢより大きいか否か判別される。所定レベルＢ
より小さいと判別した時、または、周波数１／２×ｆD
が受信バンド内に無い時、Ｓ７に移る。Further, in the controller 12, the PLL
If the frequency 2 × f D does not exist in the reception band before the circuit 10 is controlled, the process proceeds to S4, and if so, the above-described operation is performed. Moving to S5, when the controller 12 controls the PLL circuit 10 to be in the receiving state of 1/2 times / 1/2 × f D of the frequency of the desired broadcasting station, the controller 12 controls the frequency of 1/2 × It is determined whether f D exists in the reception band. When the signal is in the reception band, the received RF signal has a frequency of 1/2 × f D
The L circuit 10 is controlled. In this state, the S meter circuit 11
Detects the electric field strength of a broadcasting station having a frequency of 1/2 × f D. The controller 12 determines whether or not the detected electric field strength is higher than a predetermined level B. Predetermined level B
When it is determined that it is smaller, or frequency 1/2 × f D
If is not within the reception band, the process proceeds to S7.
【００１７】また、Ｓ４及びＳ５において、コントロー
ラ１２がＳメータ回路１１から検出された電界強度を所
定レベル以上の大きさであると判別した場合、Ｓ６に移
り、コントローラ１２は切換回路６に切換信号を発生
し、切換回路６は広帯域増幅器５の出力信号を混合回路
７に印加するように切換わる。また、コントローラ１２
は第１及び第２増幅回路１３及び１５を制御し、第１及
び第２増幅回路１３及び１５の増幅率を第１の増幅率よ
り大きい第２の増幅率と成される。以上の動作後、Ｓ７
に移る。Further, in S4 and S5, when the controller 12 determines that the electric field strength detected from the S meter circuit 11 is equal to or higher than a predetermined level, the process proceeds to S6, and the controller 12 sends a switching signal to the switching circuit 6. And the switching circuit 6 switches to apply the output signal of the wide band amplifier 5 to the mixing circuit 7. In addition, the controller 12
Controls the first and second amplification circuits 13 and 15, and the amplification factors of the first and second amplification circuits 13 and 15 are set to a second amplification factor that is larger than the first amplification factor. After the above operation, S7
Move on to.
【００１８】Ｓ７において、受信ＲＦ信号をｆDに戻
し、ＡＭラジオ受信機は希望放送局を受信し通常動作に
なる。通常動作において、抵抗３４の一端から発生する
出力信号は第１増幅回路１３において増幅され、第１レ
ベル検出回路１４に印加される。第１レベル検出回路１
４において、Ｖ−Ｉ変換することによって、抵抗３４の
一端から発生する出力信号のレベルを検出する。抵抗３
４の一端から発生する出力信号は、ＦＥＴ３１に流れる
電流の大きさを表わしている。また、切換回路６の出力
信号が第２増幅回路１５で増幅され、第２レベル検出回
路１６に印加される。第２レベル検出回路１６におい
て、Ｖ−Ｉ変換することによって、切換回路６の出力信
号のレベルを検出する。第１及び第２レベル検出回路か
ら発生する検出電流によりＲＦＡＧＣ回路１７及び減衰
制御回路１８が動作する。前記検出電流に基づき、ＲＦ
ＡＧＣ回路１７はＡＧＣトランジスタ１９及び２０に印
加するベース電圧を制御することによってＦＥＴ３１の
ソース・ドレイン間の電圧を制御することによって、Ｒ
Ｆ増幅回路３の増幅率が制御され、また、減衰制御回路
１８は減衰回路２に印加する電圧を制御することにより
受信ＲＦ信号を減衰させることにより、受信ＲＦ信号の
レベルを制御する。以上の動作により、ＡＧＣ動作が行
われている。In step S7, the received RF signal is returned to f D , and the AM radio receiver receives the desired broadcasting station and becomes the normal operation. In normal operation, the output signal generated from one end of the resistor 34 is amplified in the first amplifier circuit 13 and applied to the first level detection circuit 14. First level detection circuit 1
In 4, the level of the output signal generated from one end of the resistor 34 is detected by performing V-I conversion. Resistance 3
The output signal generated from one end of 4 represents the magnitude of the current flowing through the FET 31. The output signal of the switching circuit 6 is amplified by the second amplifier circuit 15 and applied to the second level detection circuit 16. The second level detection circuit 16 detects the level of the output signal of the switching circuit 6 by performing V-I conversion. The RFAGC circuit 17 and the attenuation control circuit 18 operate by the detection current generated from the first and second level detection circuits. RF based on the detected current
The AGC circuit 17 controls the voltage between the source and drain of the FET 31 by controlling the base voltage applied to the AGC transistors 19 and 20,
The amplification factor of the F amplifier circuit 3 is controlled, and the attenuation control circuit 18 controls the voltage applied to the attenuation circuit 2 to attenuate the received RF signal, thereby controlling the level of the received RF signal. The AGC operation is performed by the above operation.
【００１９】[0019]
【発明の効果】本発明に依れば、希望受信局の２倍及び
１／２倍の周波数をもつ放送局が所定レベル以上の電界
強度をもつ時、非線形素子を持つＲＦ同調回路から非線
形素子を持たない広帯域増幅器に切換えると共に、ＡＧ
Ｃ回路の感度を上げることにより受信ＲＦ信号のレベル
を低く制限するので、混信の発生を抑えることができ
る。According to the present invention, when a broadcasting station having frequencies twice and 1/2 times as high as that of a desired receiving station has an electric field strength of a predetermined level or more, the RF tuning circuit having the nonlinear element changes from the non-linear element to the non-linear element. Switch to a wide band amplifier that does not have
Since the level of the received RF signal is limited to a low level by increasing the sensitivity of the C circuit, the occurrence of interference can be suppressed.
【図１】本発明の一実施例を示す図である。FIG. 1 is a diagram showing an embodiment of the present invention.
【図２】従来例を示す図である。FIG. 2 is a diagram showing a conventional example.
【図３】実施例の動作を説明するフローチャートであ
る。FIG. 3 is a flowchart illustrating the operation of the embodiment.
１ アンテナ ２，５９ 減衰回路 ３，５１ ＲＦ増幅回路 ４，５２ ＲＦ同調回路 ５ 広帯域増幅回路 １３，１５ 第１及び第２増幅回路 １４，１６ 第１及び第２レベル検出回路 1 Antenna 2,59 Attenuation circuit 3,51 RF amplification circuit 4,52 RF tuning circuit 5 Wideband amplification circuit 13,15 First and second amplification circuit 14,16 First and second level detection circuit
Claims (2)
おいて、希望放送局の受信後前記希望放送局の２倍また
は１／２倍の少なくとも一方の周波数をもつ局を受信さ
せる手段と、前記局の電界強度が所定レベルであるか否
か検出する手段と、前記電界強度が所定レベル以上であ
る時ＡＧＣ回路の感度を上げると共に広帯域ＲＦ信号が
混合回路に印加されるように動作させる手段を備えたこ
とを特徴とするＡＭラジオ受信機。1. An AM radio receiver having an AGC circuit, which receives a station having at least one frequency that is two times or one half the frequency of the desired broadcasting station after receiving the desired broadcasting station, and the station. Means for detecting whether or not the electric field strength is at a predetermined level, and means for increasing the sensitivity of the AGC circuit when the electric field strength is at or above the predetermined level and operating so that a broadband RF signal is applied to the mixing circuit. AM radio receiver characterized by that.
／２倍及び２倍の周波数をもつ局を受信させる手段を備
えたことを特徴とする請求項１記載のＡＭラジオ受信
機。2. After receiving the desired broadcasting station, one of the desired broadcasting stations is received.
2. An AM radio receiver as claimed in claim 1, characterized in that it comprises means for receiving stations with a frequency of x / 2 and x2.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15957493A JP3197686B2 (en) | 1993-06-29 | 1993-06-29 | AM radio receiver |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15957493A JP3197686B2 (en) | 1993-06-29 | 1993-06-29 | AM radio receiver |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0722975A true JPH0722975A (en) | 1995-01-24 |
| JP3197686B2 JP3197686B2 (en) | 2001-08-13 |
Family
ID=15696691
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15957493A Expired - Fee Related JP3197686B2 (en) | 1993-06-29 | 1993-06-29 | AM radio receiver |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3197686B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7171180B2 (en) | 2003-08-29 | 2007-01-30 | Sanyo Electric Co., Ltd. | AM receiver circuit performing sound quality compensation of AM detection output signal |
| US7269401B2 (en) | 2003-08-28 | 2007-09-11 | Sanyo Electric Co., Ltd. | Signal processing circuit for tuner which applies signal processing based on variation in frequency of intermediate frequency signal |
| US7664197B2 (en) | 2004-03-30 | 2010-02-16 | Sanyo Electric Co., Ltd. | AM receiving circuit |
-
1993
- 1993-06-29 JP JP15957493A patent/JP3197686B2/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7269401B2 (en) | 2003-08-28 | 2007-09-11 | Sanyo Electric Co., Ltd. | Signal processing circuit for tuner which applies signal processing based on variation in frequency of intermediate frequency signal |
| US7171180B2 (en) | 2003-08-29 | 2007-01-30 | Sanyo Electric Co., Ltd. | AM receiver circuit performing sound quality compensation of AM detection output signal |
| US7664197B2 (en) | 2004-03-30 | 2010-02-16 | Sanyo Electric Co., Ltd. | AM receiving circuit |
Also Published As
| Publication number | Publication date |
|---|---|
| JP3197686B2 (en) | 2001-08-13 |
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