JPH09232985A - Radio receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To receive a modulator output or an antenna output switchingly without a tuning operation by providing a tuner circuit demodulating an output of the FM modulator or the antenna output, a means detecting which of them is selected, and a control means providing prescribed frequency information to the tuner circuit. SOLUTION: A control circuit 16 gives minimum frequency data at a reception band stored in a program memory 17 to a tuner circuit 11 and stores the data to a data memory 14. When an up-down key is operated, the control circuit 16 gives revised frequency information to the circuit 11 and stores it to the memory 14. When a CD player 30 is set to a play state, an FM modulator 21 is operated and a relay switch 26 selects its output. When the control circuit 16 detects it with a play signal from a repeater 20 that the player 30 is in the play state, the frequency information of the modulator 21 in the memory 17 is given to the circuit 11, which is turned to the output frequency of the modulator 21 and an audio signal from the player 30 is reproduced from a speaker 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an F for FM-modulating the output of an audio device such as a compact disc player.
The present invention relates to a radio receiver capable of receiving the output of an M modulator.

[0002]

2. Description of the Related Art In recent years, a so-called FM modulator has been commercialized, in which an output signal of a compact disc player (hereinafter referred to as a CD player) is FM-modulated and given to an antenna input of a radio receiver (for example, CDY manufactured by Sanyo Electric Co., Ltd.).
-M30).

Then, to the FM modulator, both the FM modulation output of the CD player and the antenna output by the FM modulator are input, and the play signal of the CD player (a disc is inserted into the CD player to enter the play state). A device for switching and selecting the FM modulation output and the antenna output of the CD player based on the signal (indicating that) is given to the radio receiver.

[0004]

By the way, in the above configuration, when listening to the CD while listening to the radio,
It is necessary to set the reception frequency of the radio receiver to the output frequency of the FM modulator after setting the CD player to the play state, and when listening to the radio that was previously listened to while listening to the CD, the CD player is stopped. It was necessary to set the radio receiver to the original frequency after setting to. Therefore, in any of the above cases, C
Two operations are required on the D player and the radio receiver side, and there is a problem in safety in the case of mounting on a vehicle. Also, C
From the operation of the D player to the operation of the radio receiver, the radio receiver is untuned (the output frequency of the FM modulator is set to a frequency other than the broadcast frequency), and noise is generated.

Incidentally, for example, in Japanese Patent Laid-Open No. 3-50919, the station data of the receiving station which has been received up to now is stored in a memory circuit by operating the interrupt key, and the playback key and the like are operated. And an audio device such as a CD are operated, and when a timer measures a predetermined time thereafter, the reception of the station data in the memory circuit is resumed.
Japanese Patent Laid-Open No. 139125, when a radio receiver having a traffic information receiving function detects that the reception intensity of traffic information has dropped to a predetermined level, the operation of the radio receiver is performed according to the operating condition before the start of reception. We have disclosed what will restore the.

However, these techniques merely return to the original state automatically after the end of a predetermined operation, and automatically adjust the reception frequency of the tuner circuit based on the selection of the output of the FM modulator or the antenna output. It is not intended to set motivation for solving the above problems.

[0007]

A radio receiver according to the present invention comprises a tuner circuit for demodulating either an output of an FM modulator for FM-modulating the output of an audio device such as a CD player or an output of an antenna, and the FM circuit. Detecting means for detecting whether the output of the modulator or the antenna output is selected; and, when the FM modulator is selected, frequency information related to the output frequency of the FM modulator is given to the tuner circuit, and the antenna output is selected. In this case, the control means gives frequency information related to the reception frequency before selecting the output of the FM modulator to the tuner circuit.

[0008]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a state in which a CD player (30) is connected to a radio receiver (10) of the present invention via a relay device (20).

First, the relay device (2) will be described.
(21) is a predetermined frequency (generally set to a frequency other than the broadcast frequency) of the audio signal from the CD player (30)
It is an FM modulator that performs FM modulation with. Reference numeral (22) is a power supply switching circuit composed of transistors (23) and (24) for playing signals (CD) from the CD player (30).
The transistors (23) and (24) are turned on and off by the H level when the player is in the play state and the L level when the player is in the stop state to control the power supply to the FM modulator (21). That is, when the CD player (30) is in the play state, the FM modulator (21) is activated, and in the stop state, the FM modulator (21) is stopped. (25) is a relay switch for switching and selecting the output of either the FM modulator (21) or the antenna (26), and (27) is the relay switch (25).
Is a relay coil for controlling and is connected to the transistor (28). This transistor (28) is also turned on / off by the play signal of the CD player (30) to control the power supply to the relay coil (27), whereby the relay is played when the CD player (30) is in the play state. The output of the FM modulator (21) is selected by the switch (25), and the output of the antenna (26) is selected by the relay switch (25) in the stop state.

Next, the radio receiver (10) will be described. Reference numeral (11) is a tuner circuit for receiving the output signal of the relay switch (25) of the relay device (20) and performing FM demodulation, and the local oscillation circuit is constituted by a PLL circuit. (1
Reference numeral 2) is an amplifier for amplifying the output signal of the tuner circuit (11), the output of which is connected to the speaker (13). (14) is a data memory consisting of RAM, (15)
Is a key circuit including an up-down key and the like. (16)
Is a control circuit for controlling each circuit based on the program written in the program memory (17) composed of ROM,
The play signal of the CD player (30) is input through the relay circuit (20).

FIG. 2 shows a flow chart of a program written in the program memory (17) of the radio receiver (10), and the operation will be described based on this.

First, when the power is turned on, the control circuit (1
6) gives frequency information relating to the lowest frequency of the reception band stored in the program memory (17) in advance to the tuner circuit (11) and stores it in the data memory (14) (steps S-1, 2). In this state, the tuner circuit (11) tunes to the lowest frequency, but if the up-down key is operated in this state, the control circuit (16) changes the reception frequency according to the operation. Therefore, frequency information relating to the changed reception frequency is given to the tuner circuit (11) and stored in the data memory (14) (steps S-3, S8,
9).

Here, when the user inserts the disc into the CD player (30) and operates the play key to set the CD player (30) in the play state, as described above, the F
The relay switch (25) selects the output of the FM modulator (21) as the M modulator (21) is activated. Then, when the control circuit (16) detects that the CD player (30) is in the play state by the play signal from the relay device (20), the program memory (1
Frequency information relating to the output frequency of the FM modulator (21) stored in advance in (7) is stored in the tuner circuit (1).
1) to tune the tuner circuit (11) to the output frequency of the FM modulator (21) (step S-4,
5). As a result, the audio signal of the CD player (30) is reproduced from the speaker (13).
Incidentally, while the output signal of the FM modulator (21) is being received, the reception frequency cannot be changed by the key circuit (15).

Next, when the user operates the stop key of the CD player (30) to set the CD player (30) in the stop state, the FM modulator (21) is stopped and the relay switch ( 25) selects the output of the antenna (26). In addition, the control circuit (16) which has detected that the CD player (30) is in the stop state by the play signal is the data memory (14).
Then, the frequency information is read out and given to the tuner circuit (11) (steps S-6 and 7). This allows
It is possible to tune to the frequency that was tuned before switching to the FM modulator (21) side.

[0015]

Since the radio receiver of the present invention is constructed as described above, for example, when the CD player is set in the play state, the radio receiver is automatically tuned to the output frequency of the FM modulator and the CD player is operated. When set to the stop state, it will automatically tune to the original reception frequency,
Does not require tuning operation at the radio receiver. Also,
Since there is no non-tuning period at the time of each switching, noise can be prevented.

[Brief description of drawings]

FIG. 1 is a CD of a radio receiver of the present invention via a relay device.
The block diagram of the state which connected the player.

FIG. 2 is a flowchart of a program written in a program memory of the radio receiver of the present invention.

[Explanation of symbols]

 10 Radio Receiver 11 Tuner Circuit 14 Data Memory 16 Control Circuit 17 Program Memory 20 Relay Device 21 FM Modulator 30 CD Player

Claims (1)

[Claims] 1. A tuner circuit for demodulating either the output of an FM modulator for FM-modulating the output of an audio device such as a compact disc player or the output of an antenna, and either the output of the FM modulator or the output of the antenna is selected. Detecting means for detecting whether the FM modulator is selected, and when the FM modulator is selected, frequency information related to the output frequency of the FM modulator is given to the tuner circuit, and when the antenna output is selected, before selecting the output of the FM modulator And a control means for giving the tuner circuit frequency information related to the reception frequency of the radio receiver.