JPS63166070A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To enable only a sound multiplex television broadcast to be recorded automatically, by setting a magnetic recording and reproducing device at a recording mode when a sound multiplex broadcast discrimination signal is outputted from a sound multiplex discrimination circuit, and setting the device at a recording stop mode when a monoral broadcast discrimination signal is outputted. CONSTITUTION:At the time of multiplex broadcasting, a discrimination circuit 12 outputs a DC voltage of H, and turns ON an electronic switch 17, and a microcomputer 19 discriminates the fact, and sets the magnetic recording and reproducing device at the recording mode. When no multiplex broadcast is put on the air, the discrimination circuit 12 outputs a DC voltage of L and turns ON an electronic switch 18, and the microcomputer 19 discriminates the fact, and sets the magnetic recording and reproducing device at a transient stop mode when a command to record only the sound multiplex television broadcast is received. By providing an operation mode switching means 20 operated in such a way, it is possible to select and record only the sound multiplex television broadcast automatically.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a magnetic recording and reproducing device having recording and reproducing functions for audio multiplex television broadcasting.

[Prior Art] Fig. 2 is a block circuit diagram showing the configuration of a receiving system of a conventional magnetic recording/reproducing device of this type, in which (1) is a tuner, (2)
(3) is an audio intermediate frequency detection circuit, and (4) is an audio FM detection circuit.

(5) is B, P, F that separates the sub-channel signal and control channel signal, (8) is an amplitude control circuit, (7) is a sub-carrier FM detection circuit that detects the sub-channel signal, (8)
is a de-emphasis circuit, (9) beams, P, F, (10
) is a band amplification circuit, (11) is a control signal AM detection circuit that detects a control channel signal into a sine wave, and (12) is a multiplex broadcast discrimination circuit that determines whether it is a multiplex broadcast or a monaural broadcast.

(13) is P for generating a reference signal for discrimination.

The L and L circuits, (14) are matrix circuits, (15) are LED drive circuits that cause LEDs to emit light during multiple broadcasting, and (5) to (15) constitute an audio multiplex demodulation circuit (1B).

Next, the operation will be explained. From among the multiplexed composite signals extracted from the audio FM detection circuit (4).

B, P, F (5) to output sub-channel signals (18 to 4
7KH2') and control channel signal (55, 25KH
2) Separate. The subchannel signal is a subcarrier FM
The detection circuit (7) performs FM detection and returns it to the sub audio signal.The control channel signal is detected by the control signal AM detection circuit (11).
) is detected as a sine wave of 922.5) 1 or +182.5H2, compared with the frequency of P L L (13), and the discrimination circuit (12) discriminates whether it is a stereo broadcast or a double audio. The matrix circuit (14) and the LED drive circuit (15) are controlled by the mode signal output.

[Problems to be Solved by the Invention] Conventional magnetic recording and reproducing devices are configured as described above, so in order to record only audio multiplex broadcasts, it is necessary to manually stop recording when receiving monaural broadcasts. This operation is complicated, and there is also the problem that monaural broadcasts are also recorded when scheduled recording/recording is performed.

This invention was made to solve the above-mentioned problems, and when it is intended to record only audio multiplex broadcasts, it is possible to obtain a magnetic recording and reproducing device that automatically stops the recording operation during monaural broadcasts. The purpose is to

[Means for Solving the Problems] The magnetic recording and reproducing device according to the present invention detects that it is an audio multiplex broadcast based on the output signal of the control channel signal discrimination circuit, and detects the magnetic recording and reproducing device if it is an audio multiplex broadcast. It is equipped with a control means for setting the recording mode to a pause mode or a stop mode in the case of monaural broadcasting.

[Operation] The control means in the present invention includes a voice multiplex discrimination circuit,
When the audio multiplex broadcast discrimination signal is being output, the magnetic recording/reproducing device is controlled to be in the recording mode, and when the monaural broadcast discrimination signal is being output, it is controlled to be in the recording stop mode.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to FIG. 1. In FIG. 0, the parts given the same reference numerals as those of the conventional device shown in FIG. 2 are the same, so the explanation will be omitted. In Figure 0, (17) is an electronic switch that is turned on by a discrimination signal indicating audio multiplex broadcasting output from the discrimination circuit (12);
1B) is an electronic switch that is turned on by a discrimination signal indicating monaural broadcasting; (19) is an electronic switch that is turned on when the microcomputer is instructed to record only audio multiplex television broadcasting. When it is, a control signal is output to set the magnetic recording/reproducing device (not shown) to recording mode, and the electronic switch (18) is turned on.
When the recording mode is set, a control signal to temporarily stop recording or to set the stop mode is output, and (17) to (19) constitute an operation mode switching means (20).

Next, the operation of this embodiment will be explained.

Whether the received television broadcast is an audio multiplex broadcast or not.
The conventional method shown in Fig. 2 is used until the 1 discrimination circuit (12) determines whether it is a monaural broadcast and the 1/) logic circuit (eye) and the LED drive circuit (15) are controlled by the 1 discrimination signal. Since it is the same as the device, detailed explanation will be omitted.

During multiplex broadcasting, (12) the discrimination circuit is the same as the conventional device shown in Fig. 2 up to the point where it is controlled by outputting a DC voltage of ) is turned ON, and the microcomputer (I8) discriminates this and puts the magnetic recording/reproducing device into the recording mode.

If it is not a multiplex broadcast, the discrimination circuit (12) outputs a DC voltage of "L" and turns on the electronic switch (18).
The microcomputer (19) discriminates this and puts the magnetic recording/reproducing device in a pause mode if it receives a command to record only the audio multiplex television broadcast.

By providing the operation mode switching means (20) that operates in this manner, it is possible to automatically select and record only the audio multiplex television broadcast if a command is given to record only the audio multiplex television broadcast. is obtained.

In the above embodiment, the operation mode switching means (20) turns the electronic switches (17) and (18) ON10FF using the discrimination signal output from the discrimination circuit (12), which is discriminated by the microcomputer (19). Although a configuration is shown in which the operation mode of the magnetic recording and reproducing apparatus is switched by switching the operation mode, a configuration may also be adopted in which the determination signal of the determination circuit (!2) is input directly to the microcomputer (18) to switch the mode.

[Effects of the Invention] As described above, according to the present invention, when receiving a command to record only audio multiplex television broadcasting, a discrimination circuit that indicates whether it is audio multiplex broadcasting or monaural broadcasting is provided. The apparatus is equipped with operation mode switching means that sets the magnetic recording and reproducing apparatus to a recording mode when the discrimination signal indicates audio multiplex broadcasting, and sets the magnetic recording and reproducing apparatus to recording pause mode or recording stop mode when the discrimination signal indicates monaural broadcasting. Therefore, when an instruction is given to record only the audio multiplex television broadcast, a magnetic recording/reproducing apparatus can be obtained which can automatically record only the audio multiplex television broadcast.

[Brief explanation of the drawing]

FIG. 1 is a block circuit diagram of an embodiment of the present invention, and FIG. 2 is a block circuit diagram of a conventional magnetic recording/reproducing apparatus. (!2)...Discrimination circuit, (16)...Audio multiplex demodulation circuit, (17), (1B)...Electronic switch,
(ill)...Microcomputer, (20)...
・Operation mode switching means. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Claims] (1) In a magnetic recording and reproducing device having an audio multiplex demodulation circuit, when receiving a command to record only audio multiplex television broadcasting, a discrimination circuit that determines whether it is audio multiplex broadcasting or monaural broadcasting. The magnetic recording and reproducing device is set to a recording mode when the discrimination signal is an audio multiplex broadcast, and the magnetic recording and reproducing device is set to a recording pause mode or a recording stop mode when the discrimination signal is not an audio multiplex broadcast. Features of magnetic recording and reproducing device.