JPH08214381A - Portable audio equipment - Google Patents

Abstract

PURPOSE: To provide improved audio signals at all times even when a radio wave condition deteriorates by wire-transmitting the audio signals through a cable. CONSTITUTION: The audio signals L and the audio signals R reproduced in an audio signal reproducing circuit 2 are amplified in audio signal amplifier circuits 3 and 4. Also, mode data MD for indicating the operation information of a main body 1 or the like are formed in a microcomputer 5, the formed mode data MD are supplied to a high-pass filter 6 and the signal components of an audible band are removed. The signals MD are supplied to an adding circuit 7 and added to the amplified audio signals L and multiplexed signals (L+MD) are formed. The multiplexed signals and the amplified audio signals R are passed through output audio signal switching circuits 60 and 61, supplied to an external audio output terminal 64, passed through the cable and transmitted to a remote controller. Further, they are passed through an input audio signal switching circuit, supplied to the audio signal amplifier circuit and reproduced in an acoustic unit.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a portable audio device such as a headphone stereo or a portable compact disc player.

[0002]

2. Description of the Related Art Recently, a portable audio device such as a headphone stereo or a portable compact disc player has a voice transmitting device (hereinafter referred to as "main body") having a voice signal transmitting means and an operation control signal receiving means in order to expand its operability. "
And a voice receiving device (hereinafter, referred to as a "remote control") having a voice signal receiving means and an operation control signal transmitting means.

A conventional wireless portable audio device will be described below. FIG. 4 is a block diagram showing a configuration of a main body 1 of a conventional portable audio device.

In FIG. 4, a reproduced left channel audio signal (hereinafter referred to as "L") and a reproduced right channel audio signal (hereinafter referred to as "R") are audio signal amplifier circuits 3 of an audio signal reproduction circuit 2. It is amplified by 4. Further, in the microcomputer 5, mode data MD indicating operation information of the main body 1 is formed, and the formed mode data MD is supplied to the high pass filter 6 to remove the audible band signal component.
The mode data MD from which the audible band component has been removed is supplied to the adder circuit 7 and added to the audio signal L amplified by the audio signal amplifier circuit 3 to form a multiplexed signal (L + MD). The left channel multiplexed signal (L + MD) and the audio signal R amplified by the audio signal amplifier circuit 4 are transmitted through the FM modulator circuits 9 and 10 of the audio signal transmission circuit 8 to the LC oscillator 1
1 and 12, and are converted into FM signals FL0 and FR0. The converted FM signals FL0 and FR0 are supplied to the mixing circuit 13. On the other hand, the oscillation signal output from the local oscillation circuit 14 is multiplied by the multiplication circuit 15, and the multiplied oscillation signal SLT is supplied to the mixing circuit 13. The FM signals FL0 and FR0 are frequency-converted by the oscillating signal SLT into the FM signals FL and FR, which are fL = fL0 + SLT and fR = fR0 + SLT. The FM signals FL and FR are amplified by the high frequency amplifier 16, supplied to the antenna 17, and transmitted to the remote controller 18.

FIG. 5 shows a remote controller 1 of a conventional portable audio device.
8 is a block diagram showing a configuration of No. 8. In FIG. 5, the FM signals FL and FR transmitted from the main body 1 are received by the antenna 20 of the audio signal receiving circuit 19, and are supplied to the mixing circuit 22 through the antenna tuning circuit and the high frequency amplifier circuit 21. On the other hand, the oscillation signal output from the local oscillation circuit 23 is multiplied by the multiplication circuit 24, and the multiplied oscillation signal SLR is supplied to the mixing circuit 22. FM signal FL,
FR is a mixing circuit 22, and the carrier frequencies fL1 and fR1 are frequency-converted into intermediate frequency signals FL1 and FR1 of fL1 = fL-SLR and fR1 = fR-SLR by the oscillation signal SLR.
The intermediate frequency signals FL1 and FR1 are supplied to the FM detection circuits 29 and 30 through the intermediate frequency filters 25 and 26 and the intermediate frequency amplifiers 27 and 28, and the multiplexed signals (L +
MD) and the audio signal R are demodulated. This multiplexed signal (L
+ MD) and the audio signal R are respectively supplied to the audio units 35 and 36 through the audio signal amplifier circuits 33 and 34 adjusted by the volume adjusting circuit 32 of the audio signal reproducing circuit 31 and reproduced. Here, a high cut filter for removing the mode data MD is added to the audio signal amplification circuit 33, and only the audio signal L is supplied to the acoustic unit 35.

Further, the multiplexed signal (L + MD) is supplied to the high-pass filter 37, the audio signal L is removed, and only the mode data MD is taken out. This mode data MD is supplied to the waveform shaping circuit 38 and shaped into the original binary signal MD, and this binary signal MD is supplied to the microcomputer 39.

In the microcomputer 39, the bit data of the original mode data is detected from the supplied signal MD to detect the operation information of the main body 1 and the LCD 40 is driven and operated according to the detection signal. Information etc. is displayed.

Further, the remote controller 18 has a remote control function for remotely controlling the main body 1. When the operation button 41 is operated on the remote controller 18, data corresponding to the operation is output from the microcomputer 39 which is the operation control signal generating means. The output signal MO is supplied to the FM modulation circuit 43 and the LC oscillator 44 of the operation control signal transmission circuit 42 and converted into the FM signal FO0. This converted F
The M signal FO0 is supplied to the mixing circuit 45. On the other hand, the oscillation signal output from the local oscillation circuit 46 is multiplied by the multiplication circuit 47, and the multiplied oscillation signal SOR is mixed.
Is supplied to. The FM signal FO0 is frequency-converted by the oscillating signal SOR in the mixing circuit 45, and the carrier frequency fO is converted into the FM signal FO of fO = fO0 + SOR. This FM signal FO
Is amplified by the high frequency amplifier 48, supplied to the antenna 49, and transmitted to the main body 1. 50 is a power supply battery for the remote controller 18.

In the main body 1 shown in FIG. 4, the remote controller 18
The FM signal FO transmitted from is received by the antenna 52 of the operation control signal receiving circuit 51, and is supplied to the mixing circuit 54 through the antenna tuning circuit and the high frequency amplifying circuit 53. On the other hand, the oscillation signal output from the local oscillation circuit 55 is multiplied by the multiplication circuit 56, and the multiplied oscillation signal SOT is supplied to the mixing circuit 54. The FM signal FO is subjected to frequency conversion of the carrier frequency fO1 into the intermediate frequency signal FO1 of fO1 = fO−SOT by the oscillation signal SOT in the mixing circuit 54. The intermediate frequency signal FO1 is supplied to the FM detection circuit 59 through the intermediate frequency filter 57 and the intermediate frequency amplifier 58,
The operation control signal MO is demodulated. This operation control signal MO
Is supplied to the microcomputer 5 which is the operation control processing means, and controls the main body 1 in accordance with the operation control signal MO transmitted from the remote controller 18.

[0010]

However, in the above-described portable audio device in which the main body 1 and the remote controller 18 are wireless, the positions of the main body 1 and the remote controller 18 are transmitted and received because they are transmitted and received by weak radio waves. There is a problem that the radio wave condition (reception condition) may be deteriorated due to the relation, noise from the outside, and the like. Further, when used near a transmitter / receiver having the same or near frequency of the transmission carrier frequency (for example, when used near the same model), there is a problem such as interference of transmitted radio waves. further,
When the battery, which is the source of the power supply voltage for the main body 1 and the remote controller 18, is exhausted, these devices cannot be used.

The present invention is intended to solve the above problems,
Providing a portable audio device that always provides a good audio signal even when the radio wave condition deteriorates due to interference or noise from the outside and enables the device to be used even when the battery that is the source of the power supply voltage is exhausted The purpose is to do.

[0012]

In order to achieve the above object, the present invention provides an external audio output terminal for outputting an audio signal to the outside in a main body, and an FM of an audio signal transmitting circuit for reproducing reproduced audio signals of left and right channels. Output audio signal switching means for switching from the modulation circuit to the external audio output terminal, control code conversion means for converting the operation control signal from the voltage control signal to the code control signal without changing the operation control signal processing means, and the external audio output terminal. By connecting a cable to the switch, the input operation control signal is switched from the path directly supplied to the operation control signal processing means to the path supplied to the operation control signal processing means after being converted into a code control signal by the control code conversion means. An external audio input terminal for inputting an external audio signal, and an external audio signal, which have input control signal switching means. By connecting a cable to the input terminal, the input audio signal switching means for switching the audio input of the audio signal amplifying means of the left and right channels from the internal FM detection circuit to the external audio input terminal and the operation control signal generating means operate without being changed. By connecting a cable to an external voice input terminal and a control voltage conversion means for converting a control signal from a code control signal to a voltage control signal, a path for directly outputting the code operation control signal generated by the operation control signal generation means Output control signal switching means for converting the sign operation control signal to a path for converting the voltage control signal into a voltage control signal by the control voltage conversion means, external voltage supply means for using the bias voltage of the audio signal as the power supply voltage of the remote controller, and external audio input. By connecting a cable to the terminal, the internal power supply voltage supply means can be connected to the external voltage supply device. A structure having a power supply voltage switching means for switching to.

[0013]

According to the present invention, by transmitting the voice signal through the cable through the cable having the above structure, a good voice signal can be always obtained even when the radio wave condition is deteriorated due to interference or noise from the outside. In addition, by converting the operation control signal from the code control signal to the voltage control signal and converting the bias voltage of the audio signal by level conversion without changing the operation control signal generation means, the wireless transmission / reception can be performed even in the case of a wired transmission device. Remote operation control is possible as in the case of the device. Furthermore, by using the bias voltage of the audio signal as the power supply voltage of the remote controller, it is possible to operate even when the battery of the remote controller (or the main body) is exhausted.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a portable audio device of the present invention will be described in detail below with reference to the drawings. The same components as those in the conventional example described above are designated by the same reference numerals.

FIG. 1 is a block diagram showing the configuration of a main body 1 in one embodiment of the portable audio device of the present invention. However, the battery of the voltage supply source of the main body 1 is omitted in FIG.

In the main body 1, the reproduced audio signal L and audio signal R are amplified by the audio signal amplification circuits 3 and 4 of the audio signal reproduction circuit 2 which are fixed to a constant amplification degree. In addition,
The amplification degree of the audio signal is controlled by the volume control circuit 3 of the remote controller 18 described later.
It is determined by the audio signal amplifier circuits 3 and 4 adjusted by 2. Further, in the microcomputer 5, mode data MD indicating operation information of the main body 1 is formed, and the formed mode data MD is supplied to the high pass filter 6 to remove the audible band signal component. The mode data MD from which the audible band component has been removed is supplied to the adder circuit 7 and added to the audio signal L amplified by the audio signal amplifier circuit 3 to form a multiplexed signal (L + MD). The multiplexed signal (L + MD) of the left channel and the audio signal R amplified by the audio signal amplifier circuit 4 are output audio signal switching circuits 60 and 61.
Is supplied to. Here, when the main body 1 operates as a wireless audio signal transmitting device, the output audio signal switching circuit 6
0 and 61 are FM modulation circuits 9 and 1 of the audio signal transmission circuit 8.
It has switched to the 0 side. The multiplexed signal (L + MD) and the audio signal R are supplied to the LC oscillators 11 and 12 via the FM modulation circuits 9 and 10 and converted into FM signals FL0 and FR0. The converted FM signals FL0 and FR0 are supplied to the mixing circuit 13. On the other hand, the oscillation signal output from the local oscillation circuit 14 is multiplied by the multiplication circuit 15, and the multiplied oscillation signal SLT is supplied to the mixing circuit 13. FM
The signals FL0 and FR0 are generated by the mixing circuit 13 and are generated by the oscillation signal SLT.
Thus, the carrier frequencies fL and fR are frequency-converted into the FM signals FL and FR, where fL = fL0 + SLT and fR = fR0 + SLT. This FM
The signals FL and FR are amplified by the high frequency amplifier 16, supplied to the antenna 17, and transmitted to the remote controller 18.

FIG. 2 is a block diagram showing the configuration of the remote controller 18 in one embodiment of the portable audio device of the present invention, and FIG. 3 is a perspective view of the main body 1 and the remote controller 18 in a connected state.

When the remote controller 18 operates as a wireless voice signal receiving device, the FM signals FL and FR transmitted from the main body 1 are received by the antenna 20 of the voice signal receiving circuit 19, and the antenna tuning circuit and the high frequency amplifier circuit 21.
Is supplied to the mixing circuit 22 through. On the other hand, the oscillation signal output from the local oscillation circuit 23 is multiplied by the multiplication circuit 24, and the multiplied oscillation signal SLR is supplied to the mixing circuit 22. The FM signals FL and FR are mixed by the mixing circuit 22, and the carrier frequencies fL1 and fR1 are changed by the oscillation signal SLR.
Are frequency-converted into intermediate frequency signals FL1 and FR1 of fL1 = fL-SLR and fR1 = fR-SLR.
The intermediate frequency signals FL1 and FR1 are supplied to the FM detection circuits 29 and 30 through the intermediate frequency filters 25 and 26 and the intermediate frequency amplifiers 27 and 28, and the multiplexed signals (L +
MD) and the audio signal R is demodulated. The input audio signal switching circuits 62 and 63 are switched to the FM detection circuits 29 and 30 side, and this demodulated multiplexed signal (L + MD) is used.
And the audio signal R are input audio signal switching circuits 62 and 63.
Is supplied to. The multiplexed signal (L + MD) and the audio signal R are supplied to the audio units 35 and 36 through the audio signal amplifier circuits 33 and 34 adjusted by the volume adjusting circuit 32 of the audio signal reproducing circuit 31, respectively, and reproduced. Here, a high cut filter is added to the audio signal amplification circuit 33, the mode data MD is removed, and the sound unit 3
Only audio signal L is supplied to 5. Volume control circuit 32
Are controlled by the microcomputer 39, and the amplification degree is adjusted according to the operation of the operation button 41.

Further, the multiplexed signal (L + MD) is supplied to the high-pass filter 37, the audio signal L is removed, and only the mode data MD is taken out. This mode data MD is supplied to the waveform shaping circuit 38 and shaped into the original binary signal MD, and this binary signal MD is supplied to the microcomputer 39. In the microcomputer 39,
The bit data of the original mode data is detected from the supplied signal MD to detect the operation information and the like of the main body 1, and the LCD 40 is driven according to the detection signal to display the operation information and the like.

Next, when the main body 1 operates as a wired audio signal transmission device, the output audio signal switching circuits 60, 6
1 is switched to the external audio output terminal 64 side. Audio signal L and audio signal R reproduced by the audio signal reproduction circuit 2
Is amplified by the audio signal amplifying circuits 3 and 4 adjusted by the volume adjusting circuit 65. Here, the volume adjusting circuit 65 is controlled by the microcomputer 5, and the amplification degree is adjusted according to an operation control signal DO transmitted from a remote controller 18 described later. Further, in the microcomputer 5, mode data MD indicating the operation information of the main body 1 is formed, and the formed mode data MD is supplied to the high pass filter 6.
The audible band signal component is removed. The signal MD from which the audible band component has been removed is supplied to the adder circuit 7 and added to the amplified audio signal L to form a multiplexed signal (L + MD). The left channel multiplexed signal (L + MD) and the amplified audio signal R are supplied to the external audio output terminal 64 through the output audio signal switching circuits 60 and 61, and are transmitted to the remote controller 18 through the cable 66. .

When the remote controller 18 operates as a wired audio signal transmission device, the input audio signal switching circuits 62, 6
Reference numeral 3 is switched to the external audio input terminal 67 side. The external audio output terminal 64 of the main body 1 and the external audio input terminal 67 of the remote controller 18 are passed through a cable 66 connected to the main body 1
The multiplexed signal (L + MD) and the audio signal R transmitted from the audio signal R pass through the input audio signal switching circuits 62 and 63 and are supplied to the audio signal amplifier circuits 33 and 34 fixed to a constant amplification degree, and the audio unit 35. , 36. Here, a high cut filter is added to the audio signal amplifier circuit 33, the mode data MD is removed, and only the audio signal L is supplied to the acoustic unit 35. In addition,
The amplification degree of the audio signal is determined by the audio signal amplification circuits 33 and 34 adjusted by the volume adjustment circuit 32.

Further, the multiplexed signal (L + MD) is supplied to the high-pass filter 37, the audio signal L is removed and only the mode data MD is taken out. This mode data MD is supplied to the waveform shaping circuit 38 and shaped into the original binary signal MD, and this binary signal MD is supplied to the microcomputer 39. In the microcomputer 39,
The bit data of the original mode data is detected from the supplied signal MD to detect the operation information and the like of the main body 1, and the LCD 40 is driven according to the detection signal to display the operation information and the like.

Further, the remote controller 18 has a remote control function for remotely controlling the main body 1. When the remote controller 18 operates as a wireless control signal transmitting device, when the operation button 41 is operated, data corresponding to the operation is stored in the microcomputer 39.
Is generated in step S6, passes through the output control signal switching circuit 68, and is output as it is as the code operation control signal MO. The output code operation control signal MO is supplied to the LC oscillator 44 via the FM modulation circuit 43 of the operation control signal transmission circuit 42 and converted into the FM signal FO0. The converted FM signal FO0 is supplied to the mixing circuit 45. On the other hand, the oscillation signal output from the local oscillation circuit 46 is multiplied by the multiplication circuit 47, and the multiplied oscillation signal SOR is mixed.
5 is supplied. The FM signal FO0 is frequency-converted by the oscillating signal SOR in the mixing circuit 45, and the carrier frequency fO is converted into the FM signal FO of fO = fO0 + SOR. This FM signal FO
Is amplified by the high frequency amplifier 48, supplied to the antenna 49, and transmitted to the main body 1.

When the main body 1 operates as a radio control signal receiving device, the FM signal F transmitted from the remote controller 18
O is received by the antenna 52 of the operation control signal receiving circuit 51 and supplied to the mixing circuit 54 through the antenna tuning circuit and the high frequency amplifier circuit 53. On the other hand, the local oscillator circuit 5
The oscillation signal output from 5 is multiplied by the multiplication circuit 56,
The multiplied oscillation signal SOT is supplied to the mixing circuit 54. The FM signal FO is mixed by the mixing circuit 54, and the local oscillation signal S
The carrier frequency fO1 is frequency-converted by the OT to the intermediate frequency signal FO1 of fO1 = fO−SOT. The intermediate frequency signal FO1 is supplied to the FM detection circuit 59 through the intermediate frequency filter 57 and the intermediate frequency amplifier 58,
The code operation control signal MO is demodulated. The code operation control signal MO passes through the input control signal switching circuit 69, is processed by the microcomputer 5, and controls the main body 1 according to the operation control signal transmitted from the remote controller 18.

Next, when the remote controller 18 operates as a wired control signal transmission device, the output control signal switching circuit 68.
Has been switched to the control voltage conversion means 70 side. When the operation button 41 is operated, data corresponding to the operation is generated by the microcomputer 39 which is the operation control signal generation means, passes through the output control signal switching circuit 68, and is previously corresponded to the code operation control signal by the control voltage conversion means 70. The voltage operation control signal DO is converted and output. The output voltage operation control signal DO level-converts the bias voltage of the audio signal, passes through the external audio input terminal 67 and the cable 66, and passes through the main body 1
Be transmitted to.

When the main body 1 operates as a wired control signal transmission device, the input control signal switching circuit 69 is switched to the control code conversion means 71 side. The voltage-level-converted audio signal transmitted from the remote controller 18 through the cable 66 is extracted by the control code conversion means 71 as a voltage operation control signal DO and converted into a code operation control signal MO. The converted code operation control signal MO passes through the input control signal switching circuit 69, is processed by the microcomputer 5 which is the operation control signal processing means, and controls the main body 1 according to the operation control signal transmitted from the remote controller 18.

When the remote controller 18 operates as a wired signal transmission device, the power supply voltage switching circuit 72 is switched to the external voltage supply circuit 73 side. Cable 66
The external voltage extracted by the external voltage supply circuit 73 that extracts only the voltage from the bias voltage of the audio signal transmitted from the main body 1 through the power source voltage switching circuit 7
2 and is supplied as a power source for the microcomputer 39, the LCD 40 and the audio signal amplifier circuits 33, 34. Here, since the audio signal amplifier circuits 33 and 34 operate with an external voltage, they are fixed to a constant amplification degree.

As described above, according to the portable audio device of the embodiment of the present invention, the external audio output terminal 64,
The remote controller 18 is provided with an external audio input terminal 67, and the cable 66 enables it to be used as a wired audio signal transmission device for transmitting an audio signal. As a result, a good audio signal can always be obtained even when the radio wave condition deteriorates due to external noise or the like. Further, by converting the operation control signal from the code control signal to the voltage control signal and converting the bias voltage of the audio signal by level transmission, the operation control signal generating means is not changed and the wireless transmission / reception device is used even in the case of a wired transmission device. Remote operation control is possible as in the case of. Furthermore, by using the bias voltage of the audio signal as the power supply voltage of the remote controller, it becomes possible to operate even when the battery of the remote controller (or the main body) is exhausted.

In the above description, the present invention is applied to a headphone stereo type stereo cassette player, but CDs, MDs, DATs and Ds are used as recording media.
The present invention can be applied to an audio device using CC or the like.

[0030]

As described above, according to the present invention, the main body is provided with the external audio output terminal and the remote control is provided with the external audio input terminal, and the cable can be used as a wired audio signal transmission device for transmitting an audio signal by a cable. As a result, even if the radio wave condition deteriorates due to interference or noise from the outside,
A good voice signal is always obtained. In addition, by converting the operation control signal from the code control signal to the voltage control signal and converting the bias voltage of the audio signal by level transmission, the wireless transmission / reception can be performed even in the case of a wired transmission device without changing the operation control signal generation means. As in the case of the device, remote operation control is possible, there is no need to add special hardware or software changes, and wireless / wired switching is possible simply by attaching / detaching the cable. Therefore, it is advantageous in terms of operability and cost.

Furthermore, by using the bias voltage of the audio signal as the power supply voltage of the remote controller, it becomes possible to operate even when the battery of the remote controller (or the main body) is exhausted, and it is possible to operate for a long time. Have.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment of a main body of a portable audio device of the present invention.

FIG. 2 is a block diagram showing the configuration of an embodiment of a remote controller for a portable audio device of the present invention.

FIG. 3 is a perspective view of an embodiment of the main body and remote controller of the portable audio device of the present invention.

FIG. 4 is a block diagram showing a configuration of a main body of a conventional portable audio device.

FIG. 5 is a block diagram showing a configuration of a conventional remote controller for a portable audio device.

[Explanation of symbols]

 1 main body 2,31 audio signal reproducing circuit 3,4,33,34 audio signal amplifying circuit 5,39 microcomputer 6,37 high pass filter 7 adding circuit 8 audio signal transmitting circuit 9,10,43 FM modulating circuit 11,12,44 LC oscillator 13, 22, 45, 54 Mixing circuit 14, 23, 46, 55 Local oscillation circuit 15, 24, 47, 56 Multiplier circuit 16, 48 High frequency amplifier 17, 20, 49, 52 Antenna 18 Remote control 19 Voice signal receiving circuit 21, 53 Antenna tuning circuit and high frequency amplification circuit 25, 26, 57 Intermediate frequency filter 27, 28, 58 Intermediate frequency amplifier 29, 30, 59 FM detection circuit 32, 65 Volume control circuit 35, 36 Sound unit 38 Waveform shaping circuit 40 LCD 41 Operation button 42 Operation control signal transmission circuit 50 Power battery 51 Operation control Signal receiving circuit 60, 61 Output audio signal switching circuit 62, 63 Input audio signal switching circuit 64 External audio output terminal 66 Cable 67 External audio input terminal 68 Output control signal switching circuit 69 Input control signal switching circuit 70 Control voltage conversion means 71 Control Code conversion means 72 Power supply voltage switching circuit 73 External voltage supply circuit

Claims (2)

[Claims] 1. An output audio signal switching means for switching an audio signal of an audio signal reproducing circuit of the main body to an audio signal transmitting circuit and an external audio input terminal of a remote controller and an external audio output terminal connected to a cable in the main body. Control code converting means for converting an operation control signal input from the remote control side to the main body side via the cable into a code control signal from a voltage control signal, and an operation control signal input from the remote control side to the external audio output terminal. And an input control signal switching means for switching to a path to be supplied to the operation control signal processing means after being converted into a code control signal by the control code converting means. 2. An input audio signal switching means for switching an audio signal reproducing circuit to an audio signal receiving circuit and an external audio input terminal connected by a cable to an external audio output terminal of the main body, and an operation control signal generating means on a remote controller. Control voltage conversion means for converting the operation control signal generated by the code control signal into a voltage control signal; and the code control signal generated by the operation control signal generation means, converted into a voltage control signal by the control voltage conversion means. Output control signal switching means for switching to a path for outputting to an external audio input terminal, further external voltage supply means for supplying a bias voltage of an audio signal to each part, and power supply voltage for switching the internal power supply voltage supply means to the external voltage supply means. A portable audio device comprising a switching means.