JP2573288Y2 - Audio equipment - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an audio apparatus in which an optical disk player used for music reproduction or the like and a radio receiver for receiving radio signals are integrated or combined.

[0002]

2. Description of the Related Art FIG. 3 is a block diagram showing an example of the configuration of a conventional on-vehicle audio device. In FIG. 3, reference numeral 1 denotes a battery for supplying power to an automobile and various parts of the audio device. A disc player (hereinafter simply referred to as a CD player) drives an optical pickup (not shown) that reads digital information recorded by pits on a signal recording surface of a compact disc (CD) with a laser beam, and rotates the CD. It comprises a CD drive 2a for driving a spindle motor (not shown) for driving. 3 is an antenna, 4 is an antenna cable whose shield is connected to the vehicle body ground CG,
Reference numeral 5 denotes an FM modulator unit, which passes a radio signal received by the antenna 3 and input via the antenna cable 4 as it is, or modulates audio signals SL and SR output from the CD player 2 into FM radio signals. Output. In the FM modulator unit 5, reference numeral 6 denotes an audio signal SL and SR output from the CD player 2 and input through input terminals 7a and 7b.
An FM modulator circuit that modulates and outputs an M radio signal, 8 is a switch, a terminal Ta is connected to the input terminal 9, a terminal Tb is connected to the output terminal of the FM modulator circuit 6, and a common terminal Tc is connected to the output terminal 10. It is connected to the. A power supply circuit 11 supplies power supplied from the battery 1 via the power supply input terminal 12 and the ground input terminal 13 to the FM modulator circuit 6 and the CD player 2. The shield of the antenna cable 4 is connected to the ground input terminal 14, and the ground input terminal 14 is connected to the ground line 1.
5 is connected to the ground output terminal 16.

A radio receiver 17 demodulates an audio signal from a radio signal output from the output terminal 10 of the FM modulator unit 5 and input via the antenna cable 18 and the input terminal 19. Radio receiver 1
7, a radio circuit 20 demodulates an audio signal from a radio signal input through the input terminal 19 and outputs the demodulated audio signal from the output terminal 21.
Power is supplied via the second and ground input terminals 23.
The shield of the antenna cable 18 is connected to the ground input terminal 24. Reference numeral 25 denotes a speaker that converts an audio signal output from the radio receiver 17 into audio.

In such a configuration, when the operator connects the common terminal Tc of the switch 8 to the terminal Tb and then plays the CD on the CD player 2, the CD driving unit 2a
Power is supplied from the battery 1 via the power supply circuit 11, and the optical pickup and the spindle motor are driven to consume current. As a result, the audio signals SL and SR are reproduced and output by the CD player 2, and input to the FM modulator unit 5 from the input terminals 7a and 7b. Next, in the FM modulator unit 5, the audio signals SL and SR input from the input terminals 7a and 7b are input.
Is modulated by the FM modulator circuit 6 into an FM radio signal, and then input to the radio receiver 17 via the switch 8, the output terminal 10, the antenna cable 18, and the input terminal 19. Then, in the radio receiver 17, after the FM radio signal is demodulated into an audio signal, the FM radio signal is output from the output terminal 21 and the audio is output from the speaker 25.

[0005]

By the way, in the above-mentioned conventional audio equipment, the current consumption of the CD drive unit 2a includes, in addition to a DC component, an AC component (noise component: 0 to several components) due to the servo operation of the optical pickup. 100Hz)
It is included. Then, this noise component flows into the radio circuit 20 via a path shown by a broken line in FIG. 3 and is output as servo noise from the speaker 25 during CD reproduction, that is, during servo driving.

Therefore, conventionally, as a measure against noise, the impedance between the FM modulator unit 5 and the negative terminal of the battery 1 has been reduced, but there is a limit to the reduction of noise.

The present invention has been made under such a background, and has as its object to provide an audio apparatus in which servo noise of an optical pickup is not output from a speaker even when a CD is reproduced.

[0008]

The present invention relates to an optical disk player having an optical pickup for reading digital information recorded by pits on a signal recording surface of an optical disk with a laser beam, which is used for music reproduction or the like. outputs an audio signal by demodulating the modulator unit output by modulating the radio <br/> Oh frequency signal by the audio signal output from the optical disc player, a radio frequency signal received by the output signal or the antenna of the modulator unit in audio equipment having a radio receiver, between the ground terminal of the isolated said modulator unit and a ground terminal of the radio receiver, the radio
Sufficiently low impedance in the frequency band of the frequency signal, and, interposed a capacitor having a capacity sufficiently high impedance in the frequency band of the servo noise that occur Ri by <br/> the servo operation of the optical pickup It is characterized by that.

[0009]

According to the above arrangement, when the operator plays the optical disk on the optical disk player, the optical pickup reads digital information recorded by pits on the signal recording surface of the optical disk with the laser beam. As a result, an audio signal is output from the optical disc player, modulated into a radio signal in the modulator unit, and then input to the radio receiver. Then, the radio signal is output after being demodulated into an audio signal in the radio receiver. At this time, the noise component due to the servo operation of the optical pickup is blocked by the capacitor and does not flow into the radio receiver.

[0010]

An embodiment of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram showing a configuration of an audio apparatus according to a first embodiment of the present invention. In this figure, parts corresponding to the respective parts in FIG. 3 are denoted by the same reference numerals, and description thereof will be omitted. In the audio equipment shown in this figure, a capacitor 26 is connected between a ground point 15a between a ground line 15 of the FM modulator unit 5 and a ground end of the FM modulator circuit 6, and a ground output terminal 16.
Has been newly inserted. The capacity of the capacitor 26 depends on the frequency band of AM radio broadcasting (several hundred kHz) and FM
The impedance is sufficiently low in the frequency band of radio broadcasting (several tens of MHz), and the frequency band of servo noise due to the servo operation of the optical pickup (0 to several hundred H)
In z), the impedance is set to a sufficiently high value.

In such a configuration, when the operator connects the common terminal Tc of the switch 8 to the terminal Tb and then plays the CD on the CD player 2, the CD driving unit 2a
Power is supplied from the battery 1 via the power supply circuit 11, and the optical pickup and the spindle motor are driven to consume current. Thus, the audio signals SL and SR are reproduced and output by the CD player 2. Next, F
The audio signals SL and SR input from the input terminals 7a and 7b of the M modulator unit 5 are modulated into FM radio signals by the FM modulator circuit 6, and then are switched to the switch 8, output terminal 10, antenna cable 18, and input terminal 19. After that, it is input to the radio receiver 17. Then, after the FM radio signal is demodulated into an audio signal in the radio receiver 17, the FM radio signal is output from the output terminal 21 and is output from the speaker 2.
5 outputs a voice.

At this time, noise components due to the servo operation of the optical pickup are blocked by the capacitor 26 ,
Flow to the minus terminal of battery 1 via terminal 23
Therefore, it does not flow into the FM modulator unit 5 and does not flow into the radio circuit 20 via the antenna cable 18. Therefore, no servo noise is output from the speaker 25 during CD reproduction, that is, during servo driving.

Next, a second embodiment of the present invention will be described. FIG. 2 is a block diagram showing a configuration of an audio apparatus according to a second embodiment of the present invention. In this figure, parts corresponding to the respective parts in FIG.
The description is omitted. In the audio device shown in this figure, a capacitor 27 is newly inserted between the ground terminal of the FM modulator circuit 6 and the connection point 15a of the ground line 15 instead of the capacitor 26. The operation is the same as that of the first embodiment, and the description is omitted.

[0014]

[Effects of the Invention] As described above, according to the invention, an audio device combining a CD player and a radio receiver is used.
In the audio equipment, the ground end of the CD player and the
Separate the grounding end of the radio receiver and
Since the connection is made with a capacitor having a capacity, there is an effect that the servo noise of the optical pickup is not output from the speaker even when the CD is reproduced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a configuration of an audio device according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of an audio device according to a second embodiment of the present invention.

FIG. 3 is a block diagram illustrating a configuration example of a conventional audio device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Battery 2 CD player 2a CD drive part 5 FM modulator unit 6 FM modulator circuit 11 Power supply circuit 15 Ground line 16 Ground output terminal 17 Radio receiver 18 Antenna cable 20 Radio circuit 26,27 Capacitor

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H04B 1/10-1/20 G11B 20/00-20/24

Claims (1)

(57) [Scope of request for utility model registration] 1. An optical disk player having an optical pickup for reading digital information recorded by pits on a signal recording surface of an optical disk with a laser beam, used for music reproduction or the like, and an audio signal output from the optical disk player. a modulator unit for outputting modulated radio frequency signal by radio received by an output signal or an antenna of said modulator unit
In an audio device including a radio receiver for outputting an audio signal by demodulating the frequency signal, between a ground terminal of the isolated said modulator unit and a ground terminal of the radio receiver, the frequency of the radio frequency signal sufficiently low impedance in the band, and audio equipment, characterized in that sufficient impedance in the frequency band of the servo noise that occur Ri by the servo operation of the optical pickup is interposed a capacitor having a high capacity .