JPS5915200Y2 - Multichannel record demodulator - Google Patents
Multichannel record demodulatorInfo
- Publication number
- JPS5915200Y2 JPS5915200Y2 JP14067976U JP14067976U JPS5915200Y2 JP S5915200 Y2 JPS5915200 Y2 JP S5915200Y2 JP 14067976 U JP14067976 U JP 14067976U JP 14067976 U JP14067976 U JP 14067976U JP S5915200 Y2 JPS5915200 Y2 JP S5915200Y2
- Authority
- JP
- Japan
- Prior art keywords
- wave signal
- frequency
- angle
- modulated wave
- demodulator
- 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
Landscapes
- Signal Processing Not Specific To The Method Of Recording And Reproducing (AREA)
Description
【考案の詳細な説明】
本考案はマルチチャンネルレコード復調器に係り、再生
角度変調波信号伝送系にこの被角度変調波信号の搬送波
数の少なくとも２倍の逓倍周波数及びその近傍周波数を
除去する特性を有するフィルタ回路を挿入することによ
り、干渉歪による異常音を発生させることなく良好に被
角度変調波信号を復調しうるマルチチャンネルレコード
復調器を提供することを目的とする。[Detailed Description of the Invention] The present invention relates to a multi-channel record demodulator, which has a characteristic in which a reproduced angle-modulated wave signal transmission system eliminates a frequency multiplied by at least twice the carrier wave number of the angle-modulated wave signal and frequencies in the vicinity thereof. It is an object of the present invention to provide a multi-channel record demodulator that can satisfactorily demodulate an angle-modulated wave signal without generating abnormal sounds due to interference distortion by inserting a filter circuit having the following.
第１図は従来のマルチチャンネルレコード復調器の一例
のブロック系統図を示す。FIG. 1 shows a block diagram of an example of a conventional multi-channel record demodulator.
同図中、１はピックアップ・カートリッジで、これより
マルチチャンネルレコードに録音されている直接波信号
（ベースバンド信号）と被角変調波信号とがピックアッ
プ再生される。In the figure, 1 is a pickup cartridge from which a direct wave signal (baseband signal) and an angle modulated wave signal recorded on a multi-channel record are picked up and reproduced.
ここで、マルチチャンネルレコードは被角度変調波信号
の上限周波数（例えば４５に叱）まではクロストーク特
性が比較的良好なカッタヘッドによりマルチチャンネル
のオーディオ信号が切削記録されているが、このカッタ
ヘッドの左右チャンネル間のクロストーク特性が上記上
限周波数を越えた周波数帯域では悪いため、他チャンネ
ルの被角度変調波信号の中心周波数の２倍若しくはそれ
以上め逓倍周波数成分も一緒に事実上切削記録されてい
る。Here, in a multi-channel record, multi-channel audio signals are cut and recorded using a cutter head that has relatively good crosstalk characteristics up to the upper limit frequency (for example, 45) of the angle-modulated wave signal, but this cutter head Because the crosstalk characteristics between the left and right channels are poor in a frequency band exceeding the above upper limit frequency, frequency components that are twice or more than the center frequency of the angle-modulated wave signal of other channels are also effectively cut and recorded. ing.
従って、上記カートリッジ１の再生周波数特性が少なく
とも被角度変調波信号帯域以上の信号をも再生しうる特
性である場合には、上記直接波信号及び被角度変調波信
号をピックアップ再生する際に上記の逓倍周波数成分を
も一緒に再生し、これらの再生信号を復調器２内の帯域
フィルタ（又“は高域フィルタ）３及び低域フィルタ４
に夫々供給する。Therefore, if the reproduction frequency characteristic of the cartridge 1 is such that it can reproduce signals at least in the angle-modulated wave signal band, when picking up and reproducing the direct wave signal and the angle-modulated wave signal, the above-mentioned The multiplied frequency components are also regenerated, and these regenerated signals are passed through a bandpass filter (or high-pass filter) 3 and a low-pass filter 4 in the demodulator 2.
supply each.
上記低域フィルタ４は上記直接波信号を濾波してこれを
後述するミキシング回路６に供給する。The low-pass filter 4 filters the direct wave signal and supplies it to a mixing circuit 6, which will be described later.
また上記フィルタ３が高域フィルタの場合はもとより、
帯域フィルタの場合であっても通常その周波数特性は第
２図に示す如く、被角度変調波信号の搬送波周波数、例
えば３０ ｋＨｚを中心周波数とする所定範囲の通過帯
域幅を有するが、サイドロープにより６０ ｋＨｚ及び
その付近の周波数、９０ ｋＨｚ及びその付近の周波数
などの被角度変調波信号の２倍若しくは２倍を含む逓倍
周波数帯の信号はあまり減衰せずに通過してしまうため
、これらの高次妨害信号も再生被角度変調波信号と共に
検波器５に供給される。In addition, if the filter 3 is a high-pass filter,
Even in the case of a bandpass filter, its frequency characteristics usually have a pass band width within a predetermined range centered around the carrier frequency of the angle-modulated wave signal, for example 30 kHz, as shown in Figure 2, but due to side lobes. Signals in the multiplier frequency band, including twice or twice the angle modulated wave signal, such as frequencies at and around 60 kHz and frequencies at and around 90 kHz, pass through without much attenuation. The secondary interference signal is also supplied to the detector 5 together with the reproduced angle modulated wave signal.
検波器５は上記再生被角度変調波信号を検波し、この検
波信号をミキシング回路６に供給して前記直接波信号と
ミキシング（マトリックス）せしめる。The detector 5 detects the reproduced angle modulated wave signal, and supplies this detected signal to a mixing circuit 6 for mixing (matrix) with the direct wave signal.
これにより、ミキシング回路６より左側Ｌチャンネルの
第１及び第２チヤンネル信号Ｃｈ１及びｃｈ２が復調出
力される。As a result, the mixing circuit 6 demodulates and outputs the first and second channel signals Ch1 and ch2 of the left L channel.
なお、右側Ｒチャンネルの第３及び第４チヤンネル信号
についても復調器２と同−構成の復調器（図示せず）に
より復調される。Note that the third and fourth channel signals of the right R channel are also demodulated by a demodulator (not shown) having the same configuration as the demodulator 2.
然るに、この従来の復調器は、再生した被角度変調波信
号の２倍若しくは２倍を含む逓倍周波数帯の高次妨害信
号も検波器５に印加してしまうため、特に検波器５とし
てフェーズ・ロックド・ループＰＬＬを用いた場合にこ
の高次妨害信号が他チャンネルへクロストークとして影
響し、例えば他チャンネルからの高次妨害信号６０ ｋ
Ｈｚが３０ ｋＨｚの被角度変調波信号との間でビート
を発生させ、このビート周波数により被角度変調波信号
が変調され復調出力に干渉歪（異常音）を発生すること
があるという欠点を有していた。However, since this conventional demodulator also applies to the detector 5 a high-order interference signal in a frequency band that is twice the reproduced angle-modulated wave signal or in a multiplied frequency band, When a locked loop PLL is used, this high-order interference signal affects other channels as crosstalk, for example, a high-order interference signal 60k from other channels.
A beat is generated between the 30 kHz angle modulated wave signal, and the beat frequency modulates the angle modulated wave signal, resulting in interference distortion (abnormal noise) in the demodulated output. Was.
この場合、特に他チャンネルからのクロストーク分によ
る影響が最も大で、干渉歪（異常音）発生の主要因とな
っていた。In this case, the influence of crosstalk from other channels was the greatest, and was the main cause of interference distortion (abnormal sound).
本考案は上記の欠点を除去したものであり、以下第３図
と共にその一実施例につき説明する。The present invention eliminates the above-mentioned drawbacks, and an embodiment thereof will be described below with reference to FIG.
第３図は本考案になるマルチチャンネルレコード復調器
の一実施例のブロック系統図を示す。FIG. 3 shows a block diagram of an embodiment of a multi-channel record demodulator according to the present invention.
同図中、第１図と同一部分には同一符号を付し、その説
明を省略する。In the figure, the same parts as in FIG. 1 are designated by the same reference numerals, and their explanations will be omitted.
３は高域フィルタ（又は帯域フィルタ）で、マルチチャ
ンネルレコードよりの再生信号から被角度変調波信号を
分離濾波する。3 is a high-pass filter (or bandpass filter) that separates and filters the angle-modulated wave signal from the reproduced signal from the multi-channel record.
９は帯域除去フィルタ（又はトラップ回路）で、フィル
タ８の出力信号から被角度変調波信号の２倍若しくは２
倍を含む逓倍周波数帯（例えば逓倍周波数及びその±１
０％程度の範囲の周波数帯域）の信号成分のみを除去し
、被角度変調波信号のみを検波器５に供給する。9 is a band rejection filter (or trap circuit), which extracts from the output signal of filter 8 twice or twice the angle modulated wave signal.
Multiplication frequency band including multiplication frequency (e.g. multiplication frequency and its ±1
Only the signal components in the frequency band in the range of approximately 0% are removed, and only the angle-modulated wave signal is supplied to the detector 5.
従って、再生被角度変調波信号と他チャンネルからの上
記高次妨害信号との間でビートが発生することを防止で
き、これにより、フィルタ８，９を含む復調器７の復調
出力中の干渉歪（異常音）の発生を防止できる。Therefore, it is possible to prevent beats from occurring between the reproduced angle-modulated wave signal and the above-mentioned high-order interference signal from other channels, thereby causing interference distortion in the demodulated output of the demodulator 7 including the filters 8 and 9. (abnormal noise) can be prevented from occurring.
なお、上記実施例において、フィルタ８と９との接続順
序を変えても本考案の初期の目的を遠戚しうることは明
らかである。In the above embodiment, it is clear that even if the order in which the filters 8 and 9 are connected is changed, the original purpose of the present invention can be achieved in a distant manner.
また、帯域フィルタ（又はトラップ回路）９により減衰
又は除去する周波数帯域は前記逓倍周波数及びその±５
％程度の帯域でもよい。Further, the frequency band to be attenuated or removed by the bandpass filter (or trap circuit) 9 is the multiplication frequency and its ±5 frequency band.
% band may be sufficient.
上述の如く、本考案になるマルチチャンネルレコード復
調器は、マルチチャンネルの信号が直接波信号と被角度
変調波信号とされこれら両信号が多重されて録音されて
いるマルチチャンネルレコードから再生した上記両信号
より上記マルチチャンネルの信号を復調する復調器にお
いて、ピックアップカートリッジの出力側から上記被角
度変調波信号を復調検波する検波器の入力側に至る伝送
経路中に、被角度変調波信号の搬送波周波数の２倍の周
波数及びその近傍周波数（又は搬送波周波数の２倍以上
の各逓倍周波数及びそれらの近傍周波数）を減衰除去す
るフィルタ又はトラップ回路を挿入配置するよう構成し
たため、特に他チャンネルの上記搬送波周波数の２倍又
はそれ以上の逓倍周波数帯びそれらの近傍周波数が被角
度変調波信号との間で発生するビートを防止除去でき、
従ってこのビート周波数と被角度変調波信号との間で干
渉を生じることがなく復調出力中の干渉歪（異常音）を
発生させることなく良好に被角度変調波信号を復調検波
できる等の特長を有するものである。As mentioned above, the multi-channel record demodulator according to the present invention reproduces the above-mentioned signals from a multi-channel record in which the multi-channel signals are a direct wave signal and an angle-modulated wave signal, and these two signals are multiplexed and recorded. In the demodulator that demodulates the multi-channel signal from the signal, the carrier frequency of the angle-modulated wave signal is detected during the transmission path from the output side of the pickup cartridge to the input side of the detector that demodulates and detects the angle-modulated wave signal. Since the configuration is such that a filter or trap circuit is inserted to attenuate and remove the frequency twice the carrier frequency and its neighboring frequencies (or each multiplied frequency twice or more the carrier frequency and their neighboring frequencies), the above carrier frequency of other channels is inserted. It is possible to prevent and remove beats occurring between the angle-modulated wave signal and the angle-modulated wave signal whose neighboring frequencies have a frequency that is twice or more than that of
Therefore, there is no interference between this beat frequency and the angle-modulated wave signal, and the angle-modulated wave signal can be successfully demodulated and detected without causing interference distortion (abnormal sound) in the demodulated output. It is something that you have.
第１図は従来の復調器の一例のブロック系統図、第２図
は第１図の要部の一例の周波数特性を示す図、第３図は
本考案復調器の一実施例のブロック系統図である。
１・・・・・・ピックアップ・カートリッジ、２，７・
・・・・・復調器、３・・・・・・帯域フィルタ（又は
高域フィルタ）、４・・・・・・低域フィルタ、５・・
・・・・検波器、８・・・・・・高域フィルタ（又は帯
域フィルタ）、９・・・・・・帯域除去フィルタ（又は
トラップ回路）。Fig. 1 is a block diagram of an example of a conventional demodulator, Fig. 2 is a diagram showing frequency characteristics of an example of the main part of Fig. 1, and Fig. 3 is a block diagram of an embodiment of the demodulator of the present invention. It is. 1...Pickup cartridge, 2,7.
... Demodulator, 3 ... Bandpass filter (or high-pass filter), 4 ... Low-pass filter, 5 ...
. . . Detector, 8 . . . High-pass filter (or bandpass filter), 9 . . . Band-removal filter (or trap circuit).
Claims (1)
号とされこれら両信号が多重されて録音されているマル
チチャンネルレコードから再生した上記両信号より上記
マルチチャンネルの信号を復調する復調器において、ピ
ックアップ・カートリッジの出力側から上記被角度変調
波信号を復調検波する検波器の入力側に至る伝送経路中
に、被角度変調波信号の搬送波周波数の２倍の周波数及
びその近傍周波数（又は該搬送波周波数の２倍以上の各
逓倍周波数及びそれらの近傍周波数）を減衰除去するフ
ィルタ文はトラップ回路を挿入配置するよう構成したマ
ルチチャンネルレコード復調器。The multi-channel signal is a direct wave signal and an angle-modulated wave signal, and these two signals are multiplexed and recorded in a demodulator that demodulates the multi-channel signal from both signals reproduced from a multi-channel record.・In the transmission path from the output side of the cartridge to the input side of the detector that demodulates and detects the angle-modulated wave signal, a frequency twice the carrier frequency of the angle-modulated wave signal and its neighboring frequency (or the carrier frequency A multichannel record demodulator configured such that a trap circuit is inserted in a filter sentence that attenuates and eliminates each multiplied frequency (more than twice the frequency and frequencies near those frequencies).
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14067976U JPS5915200Y2 (en) | 1976-10-21 | 1976-10-21 | Multichannel record demodulator |
| DE19772747056 DE2747056A1 (en) | 1976-10-21 | 1977-10-20 | MULTI-CHANNEL RECORDING DISC PLAYBACK DEVICE |
| US05/843,856 US4152550A (en) | 1976-10-21 | 1977-10-20 | Apparatus for reproducing a multichannel record disc |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP14067976U JPS5915200Y2 (en) | 1976-10-21 | 1976-10-21 | Multichannel record demodulator |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5358502U JPS5358502U (en) | 1978-05-18 |
| JPS5915200Y2 true JPS5915200Y2 (en) | 1984-05-04 |
Family
ID=28749438
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP14067976U Expired JPS5915200Y2 (en) | 1976-10-21 | 1976-10-21 | Multichannel record demodulator |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5915200Y2 (en) |
-
1976
- 1976-10-21 JP JP14067976U patent/JPS5915200Y2/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5358502U (en) | 1978-05-18 |
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