JPH0661883A - Radio receiver - Google Patents

Abstract

PURPOSE:To record a required part at any time without advanced preparation by inputting an audio signal from a storage device converted by a D/A converter and a switched output from a tuner receiving a radio broadcast to a power amplifier. CONSTITUTION:A radio of a radio broadcast is demodulated into an audio signal by a tuner 1 and the demodulated signal is sent to an A/D converter 7 and a terminal 12 of a changeover device 3. The terminal 12 is selected by a control signal C1 to the position of a power amplifier 4, and the audio signal is transduced into a sound by a speaker 6. On the other hand, the audio signal sent to the A/D converter 7 is converted into a digital code sequentially for a prescribed period and sent to a RAM 10. On the other hand, a clock signal from a clock generator 8 is counted by a counter 9 and sequentially written in the RAM 10 by an address signal outputted from bit terminals Q0-Qn and rewritten sequentially into a newest digital code broadcast at 2nd and succeeding periods. The data are read by a control signal C2 and sounded out from a speaker via a D/A converter 11, a changeover device 3 and an amplifier 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a radio receiver, and more particularly to a radio receiver with a recording function.

[0002]

2. Description of the Related Art A conventional radio receiver with a recording function is shown in FIG.
In order to switch between a tuner 1 for receiving a radio broadcast and demodulating it into an audio signal, a tape recorder 2 for recording the audio signal, and the audio signal and the audio signal reproduced by the tape recorder 2, as shown in FIG. Switching device 3 of
It has a power amplifier 4 for amplifying an audio signal, and a speaker 6 for converting the audio signal into audio.

Next, the operation will be described. The audio signal demodulated by the tuner 1 is sent to the tape recorder 2 and the terminal I2 of the switch 3. The voice signal sent to the power amplifier 4 via the switch 3 is amplified and converted into voice by the speaker 6. On the other hand, the audio signal input to the tape recorder 2 is recorded on the magnetic tape 5 by putting the tape record 2 into a recording state.

Next, in order to reproduce the audio signal recorded on the magnetic tape 5, the switch 3 is switched to the terminal I1.
The audio signal is reproduced by rewinding the magnetic tape 5 to the recording start time and setting the tape recorder 2 in the reproduction state. The reproduced audio signal is amplified by the power amplifier 4 and converted into audio by the speaker 6.

[0005]

In this conventional radio receiver with a recording function, the tape recorder 2 is used as a recording means. Therefore, in order to record the broadcast contents, the tape recorder 2 before the broadcast start time is recorded. Had to be in a recording state. Therefore, if the tape recorder 2 is not in the recording state, it is impossible to reproduce the sound broadcast after the end of broadcasting. Also, as a method of use for solving the above-mentioned problems, there is a method of keeping the tape recorder 2 in a recording state at all times while receiving a radio broadcast, but the recording time of the magnetic tape is finite, which is not practical. Radio receivers are mainly portable and are generally battery-powered. Therefore, in a usage state in which power consumption is increased, a movable time is significantly shortened, which is not practical. Further, since the tape recorder is used as the recording means, there is a problem that there is a limit to miniaturization.

An object of the present invention is to solve the above problems and provide a compact and practical radio receiver.

[0007]

A first configuration of a radio receiver according to the present invention comprises a tuner for receiving a radio broadcast and demodulating it into an audio signal, and an analog / digital converter for converting the audio signal into a digital code. A semiconductor memory device that continuously stores the digital code; an address counter that continuously outputs an address signal to the semiconductor memory device; a clock generator that supplies a clock signal to the address counter; and the semiconductor memory device. A digital-analog converter for converting the digital code output from the device into a voice signal, and a switch for switching between the voice signal converted by the digital-analog converter and the voice signal output from the tuner and inputting it to the power amplifier And a container.

A second configuration of the radio receiver of the present invention is such that between the address counter and the semiconductor memory device, the storage capacity of the semiconductor memory device is used half by half.
It is characterized by being through an address switch.

[0009]

1 is a block diagram showing a radio receiver according to a first embodiment of the present invention.

Radio waves of radio broadcasting are demodulated into audio signals by the tuner 1 and sent to the A / D converter 7 and the terminal I2 of the switch 3. The terminal I2 is connected to the power amplifier 4 by the control signal C1.
The voice signal amplified by is converted into voice by the speaker 6. On the other hand, the audio signal sent to the A / D converter 7 is
The data is sequentially converted into a digital code at a constant cycle and sent to a semiconductor memory device, particularly a random access memory (hereinafter referred to as RAM) 10.

The address of the RAM 10 is the clock generator 8
By counting the clock signal of a constant cycle output by the address counter 9, the clock signal is continuously switched by the address signal output from the bit terminals Q0 to Qn of the address counter 9 for each count, and is written by the control signal C2. RAM1 in the state
The digital code is sequentially written into 0. RA
Counting operation 1 of the address counter 9 written in M10
The digital code for one cycle is rewritten to the latest digital code that is sequentially broadcast after the second cycle. Therefore, the digital code currently being broadcast up to one cycle before the counting operation of the address counter 9 is always written in the RAM 10.

Therefore, the recorded content is retained by stopping the counting operation of the address counter 9 by the control signal C3 after the portion of the radio broadcast requiring recording is broadcast.

Next, a method of reproducing the recorded radio broadcast will be described. RA by control signal C2
After the M10 is changed from the write state to the read state, the count operation of the address counter 9 is restarted by the control signal C3, so that the digital code from one cycle before the address counter to the stop before the count operation of the address counter is stopped. Are sequentially read from the RAM 10, converted into audio signals by the D / A (digital / analog) converter 11, and sent to the terminal 11 of the switch 3. The terminal I1 is connected to the power amplifier 4 by the control signal C1, and the sound signal amplified by the power amplifier 4 is converted into sound by the speaker 6 by the speaker 6.

FIG. 2 is a block diagram showing a second embodiment of the present invention. In FIG. 2, in the present embodiment, the RAM connected to the most significant bit terminal Qn of the address counter 9
An address switch 13 is provided between the ten address terminals An so that three states can be set by the control signal C4. Other parts are the same as in FIG.

In the first state, the address terminal An of the RAM 10 is connected to a high potential (denoted as "1" in the figure) to temporarily create a state in which the number of address terminals of the RAM 10 is reduced by one. The write operation is performed as described in the first embodiment by using 50% of the storage capacity of the above, and the control signal C3 is used after the portion (for example, the A program) requiring recording of the radio broadcast is broadcast. The counting operation of the address counter 9 is stopped and the recorded contents are held.

In the second state, the address terminal An of the RAM 10 is connected to a low potential (denoted as "0" in the figure) to temporarily create a state in which the number of address terminals of the RAM 10 is reduced by one. 50% of the memory capacity (however, the portion not used in the first state) can be used, and the counting operation of the address counter 4 is restarted by the control signal C3. In this state, the count operation of the address counter 9 is stopped by the control signal C3 after the portion (for example, B program) requiring recording of the radio broadcast is broadcast, and the recorded content is held.

By setting the two states described above, the recording time for each becomes half as compared with the first embodiment, but which of two broadcasts (A program and B program) having different broadcast time zones is used. It is possible to record without erasing either one.

In the third state, the most significant bit terminal Qn of the address counter 9 and the address terminal An of the RAM 10 are connected and the write operation is continuously performed using the storage capacity of 100% of the RAM 10. It realizes the same function as that of the first embodiment.

Further, in the first and second embodiments, it is possible to realize high speed reproduction or low speed reproduction by changing the frequency of the clock signal output from the clock generator 8 during reproduction.

The recording time according to this embodiment depends on the storage capacity of the RAM and the sampling speed of the A / D converter, but when the audio frequency is up to 1 kHz, when sampling is performed at 3 kHz, which is three times the sampling speed, in recent years It is possible to record for about 5 minutes by using a generally available 4M (1M word × 4 bit) RAM. Furthermore, if a large amount of RAM becomes available at a low price due to technological progress, it will be used for 30 minutes or 60 minutes, which is currently used in tape recorders.
It is also possible to realize the same recording time as a minute magnetic tape.

[0021]

As described above, according to the present invention, a tuner for receiving a radio broadcast and demodulating an audio signal, an A / D converter for converting the audio signal into a digital code, and the digital code are continuously connected. A semiconductor memory device that stores
An address counter for continuously outputting addresses of the semiconductor memory device, a clock generator for supplying a clock signal to the address counter, and an A / D for converting a digital code read from the semiconductor memory device into a voice signal.
Since a converter and a switching device for switching between the audio signal converted by the D / A converter and the audio signal output from the tuner and inputting it to the power amplifier are provided, it is possible to record a radio broadcast. By stopping the counting operation of the address counter after the required part is broadcasted, the required part can be recorded, and therefore without any preparation such as pressing the record button before the broadcast starts. This has the effect of recording the part that is needed at any time.

The volume of a conventional radio receiver of this type using a tape recorder as a recording means is 200 cm ^3.
Although it was before and after, according to the present invention, the semiconductor integrated circuit can be formed, so that the volume can be reduced to about 30 cm ³ which is one sixth of the conventional volume. Further, in the conventional method, the electric power of about 200 mW was consumed by using the motor for the tape recorder, but according to the present invention, the same function can be realized with the electric power of 50 mW or less.

[Brief description of drawings]

FIG. 1 is a block diagram showing a radio receiver according to a first embodiment of the present invention.

FIG. 2 is a block diagram showing a second embodiment of the present invention.

FIG. 3 is a block diagram showing a conventional technique.

[Explanation of symbols]

 1 Tuner 2 Tape Recorder 3 Switching Device 4 Power Amplifier 5 Magnetic Tape 6 Subiker 7 A / D Converter 8 Clock Generator 9 Address Counter 10 RAM 11 D / A Converter 12 Control Unit C1, C2, C3, C4 Control Signal Q0 , Q1, ~, Qn address counter output terminals A0, A1, ~, An RAM address terminals

Claims (2)

[Claims] 1. A tuner for receiving a radio broadcast and demodulating into an audio signal, an analog / digital converter for converting the audio signal into a digital code, a semiconductor memory device for continuously storing the digital code, and An address counter for continuously outputting an address signal to a semiconductor memory device, a clock generator for supplying a clock signal to the address counter, and a digital-analog converter for converting a digital code output from the semiconductor memory device into a voice signal. And a switcher for switching between the audio signal converted by the digital-analog converter and the audio signal output from the tuner and inputting to the power amplifier. 2. The radio receiver according to claim 1, wherein an address switch is provided between the address counter and the semiconductor memory device so that the storage capacity of the semiconductor memory device is used half by half. Machine.