JPH04209365A - Sound recording reswitching circuit - Google Patents

Abstract

PURPOSE:To miniaturize a packaged substrate, etc., by having a monitor switching circuit switching a monitor signal and a recording/reproducing signal and an output switching circuit switching/outputting a signal outputted fro ma switching circuit to three types of sound signals. CONSTITUTION:When the control signal 3 of an H-level is inputted, the monitor switching circuit 32 connects an input terminal (a) and output terminals 32L and 32R, and a b-input terminal and the terminals 32L and 32R when the signal 3 of an L-level is inputted. The terminals 32L and 32R are connected with an output switching unit circuit 47. The monitor signal outputted from the circuit 32 and the recording/reproducing signal are turned into three types of output signals of a stereo sound signal, a main channel signal, and a subchannel signal, by the switching of the circuit 47. Thus, a sound processing circuit 19 can assemble all circuits only by adding the signal 3, and an integrated-circuit for one tip is formed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention provides two input terminals capable of recording audio signals in stereo.
The audio recording/playback device has one set of output terminals capable of outputting audio signals in stereo, and can output an audio signal input to one input terminal while recording an audio signal input to the other input terminal. This relates to a switching circuit.

[Prior Art] Audio signals are often transmitted as stereo audio signals consisting of a main channel signal and a sub-channel signal.With the recent development of communication technology, this stereo audio signal has been transmitted by satellite in addition to terrestrial broadcasting. It is also being transmitted through broadcasting. Therefore, the equipment that receives the above audio signals is
It is necessary to be able to receive both broadcast formats, and by providing at least two sets of input terminals for stereo audio signals, it is possible to input both broadcasts at the same time.

That is, for example, in the case of a VTR that can receive satellite broadcasting,
Input terminal for terrestrial broadcasting, input terminal for satellite broadcasting, and other V
It has external input terminals that can be connected to a TR, etc., and stereo audio signals are input to these input terminals. Of the stereo audio signals separated from both of the above broadcasts, a specific stereo audio signal is selected and recorded by switching a changeover switch (see FIG. 3).

At this time, the specific stereo audio signal selected is usually
Although it is now possible to record on magnetic tape and output to a television, since terrestrial broadcasting and satellite broadcasting are simultaneously input to the VTR, for example, the stereo audio signal of terrestrial broadcasting is not recorded, but the stereo audio signal of satellite broadcasting is recorded. There is a desire to run a satellite monitor that outputs images to a television.

Furthermore, in order to monitor the satellite broadcasting stereo audio signal from the same terminal as the recording/reproducing output, an audio recording/reproducing switching circuit is provided which can output the monitor signal from an arbitrary output terminal.

Conventionally, the above audio recording/reproducing switching circuit has two sets of input terminals 51L and 51R for stereo audio signals, as shown in FIG.
・52L/52F 1 set of output terminals 53I7/53
R, a set of input terminals 52M and output terminals 53M for monaural audio signals (hereinafter referred to as monaural audio signals), and a recording/reproducing circuit 57 capable of recording and reproducing stereo audio signals and monaural audio signals. an audio processing circuit 50 provided with the audio processing circuit 50 and an input terminal 52L of the audio processing circuit 50;
- It has a switching circuit 58 connected to the output terminals 52R and 52M, and a monitor switching circuit 60 connected to the output terminals 53L and 53R of the audio processing circuit 50.

The switching circuit 58 on the input side of the audio processing circuit 50 is connected to the satellite monaural signal circuit 59 to switch between the stereo audio signal and monaural audio signal of satellite broadcasting and the stereo audio signal and monaural audio signal of terrestrial broadcasting. It is designed to be switched and input to input terminals 52L°, 52R, and 52M. These signals are recorded in the recording and reproducing circuit 57, and are switched to three types of output signals: a stereo audio signal, a king channel signal, and a sub-channel signal, in an output switching circuit 56, and then sent to output terminals 53I- and 53.
It is designed to be output from R as a recording/reproducing signal. The monitor switching circuit 60 on the output side outputs the three types of audio signals of the recording and playback signals from the output terminals 53L and 53R of the audio processing circuit 50, and also outputs the stereo audio signal as the monitor signal from the satellite broadcasting. The output signal is switched between three types of output signals.

[Problem to be Solved by the Invention] However, in the conventional audio recording/reproducing switching circuit described above, the audio processing circuit 50, the switching circuits 58 and 60, and the satellite monaural signal circuit 59 have a separate circuit configuration. Since each circuit 50, 58, 59, and 60 is
There is a problem in that the mounting board and the like become larger.

Therefore, in the conventional audio recording/reproducing switching circuit, as shown in FIG.
There is also an audio recording/reproducing switching circuit in which the switching circuit 58 and satellite monaural signal circuit 59 shown in FIG. In this case, the audio processing circuit 50 only has an additional input terminal 61 for a control signal that controls the switching circuit 55. However, even in the case of this audio recording/reproducing switching circuit, since the monitor switching circuit 60 and the audio processing circuit 50 are separate, the size of the mounting board etc. cannot be sufficiently reduced.

Alternatively, simply add the monitor switching circuit 6 to the audio processing circuit 50 described above.
0, in addition to the input terminal for the control signal that controls the monitor switching circuit 60, there is also an input terminal for inputting the stereo audio signal of satellite broadcasting into the audio processing circuit 50, and an input terminal for the monitor switching circuit 60. An input terminal for control signals is required, and the number of terminals of the audio processing circuit 50 increases.

In particular, the monitor switching circuit 60 is a four-man switch unit that converts the satellite audio signal during satellite monitoring into three types of output signals, such as a stereo signal, main audio signal, sub audio signal, and general recording/playback signal. Multiple control signals are required, and the number of terminals increases significantly. In the voice processing circuit 50 in which the number of children is increased, it is possible to sufficiently downsize the mounting board etc., but the voice processing circuit 50
When converting 0 into an IC, it is desirable that the number of input terminals and output terminals be suppressed to the minimum necessary number, so the number of terminals is insufficient.

Therefore, in the present invention, with the number of terminals suppressed,
It is an object of the present invention to provide an audio recording/reproducing switching circuit in which the input side switching circuit 58, the satellite monaural signal circuit 59, and the monitor switching circuit 60 shown in FIG. 4 can be incorporated into the audio processing circuit 50.

[Means for Solving the Problems] In order to solve the above-mentioned problems, the audio recording/reproducing switching circuit according to the present invention provides a satellite/external audio signal which is a monitor signal consisting of a main channel signal and a sub-channel signal, It is possible to switch and output a stereo playback signal, etc., into three types of audio signals: a stereo audio signal, a main channel signal, and a sub-channel signal, and output the audio signals in each of the above formats from the IMA-only output terminal. It is an audio recording/reproduction switching circuit, and the above monitor signal is input to a satellite signal or an external signal.
The signal is input from one input terminal of the Mi only input terminal, and there is a monitor switching circuit that can switch and output the monitor signal and the recording/playback signal, and a signal output from the monitor switching circuit that can output the signal in three forms. It is characterized by having an output switching circuit capable of switching to an audio signal and outputting it to an output terminal.

[Function] According to the above configuration, the monitor signal and the recording/playback signal are
After being switched and outputted by the monitor switching circuit, the output switching circuit switches to three types of output signals and outputs them. Therefore, the monitor signal and the recording/reproducing signal consisting of the main channel signal and the sub-channel signal are respectively switched to three types of audio signals when output from the output switching circuit.

At this time, since the monitor signal and the recording/reproduction signal are input to the monitor switching circuit, it is only necessary to have a switch section operated by two people, and the monitor switching circuit can be switched by a single control signal. . Furthermore, the monitor signal input to the recording/reproduction signal is input from one input terminal of the two sets of input terminals, so there is no need to newly provide an input terminal for the monitor signal. Therefore, the audio recording/reproducing switching circuit incorporates a monitor switching circuit and an output switching circuit for outputting each signal type while keeping the number of terminals to the necessary minimum, so it can be implemented as a single chip IC. Since it is possible,
It has become possible to downsize mounting boards and the like.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

As shown in FIG. 3, the audio recording/reproducing switching circuit according to the present embodiment is mounted on a VTR 1 capable of receiving, for example, satellite broadcasting. It is now possible to output satellite signals. This TV 2 has a video input terminal 2■ that can be connected to the video output terminal 1■ of the VTRI, and a video input terminal 2L・2 that can be connected to the audio output terminal IR・]L of the VTRI.
R1 and an input terminal 2T for terrestrial broadcasting are provided. The video input terminal 2■ is connected to a video display circuit 4 via a switching circuit 3, and a terrestrial broadcast tuner circuit 7 is also connected to the video display circuit 4 via the switching circuit 3. The video display circuit 4 is configured to receive the video signal from the VTR 1 and the terrestrial broadcast video signal by switching the switching circuit 3, and to output the input video signal to the cathode ray tube 5. It has become.

Furthermore, the audio input terminals 2L and 2R are connected to an audio output circuit 6 via a switching circuit 3.
A terrestrial broadcast tuner circuit 7 is also connected to the terrestrial broadcasting tuner circuit 7 via a switching circuit 3. Thereby, the stereo audio signal from the VTR 1 or the stereo audio signal of terrestrial broadcasting is input to the audio output circuit 6 by switching the switching circuit 3.

The VTRI equipped with the video output terminal 1■ and the audio output terminal IR・1[, which are connected to the television 2 described above, is also equipped with external input terminals 8■・8L・8R, and these external input terminals 8■・8L and 8R are video equipment 2 such as other VTRs.
It is now possible to connect with 7. Furthermore, this VTR1 has descramble input terminals 9■, 9L,
9R and a descramble output terminal 10V/IOA, these descramble input terminals 9■, 9
L・9R and descramble output terminal 10・IO
A is designed to enable connection with a descrambler 11 that converts encrypted satellite signals into regular signals.

The VTR 1 also includes a satellite broadcast input terminal 13 that enables connection to a satellite broadcast antenna 12, and a terrestrial broadcast input terminal 15 that enables connection to a terrestrial broadcast antenna 14.
It also includes a terrestrial broadcasting output terminal 16 connected to the input terminal 2M of the television 2 described above.

The above-mentioned terrestrial broadcasting input terminal 15 and terrestrial broadcasting output terminal 16 are the output terminal 20M of the audio processing circuit 19 and the switching circuit 29.
The terrestrial broadcasting input terminal 15 is connected to the terrestrial broadcasting tuner circuit 7 of the television 22 described above.
It is connected to a terrestrial broadcast reception tuner circuit 17 equivalent to the above. This terrestrial broadcast reception tuner circuit 17 demodulates terrestrial broadcasting into an audio signal consisting of a video signal, a stereo audio signal, and a monaural audio signal, and has an output terminal 17V for the video signal and an output terminal 17L for the stereo audio signal.・
17R and a monaural audio signal output terminal 17M.

The above output terminal 17V is connected to a video recording/reprocessing circuit 22 via a switching circuit 21, and outputs a terrestrial broadcast video signal to this video recording/reprocessing circuit 22. The terminals 17L, 17R, and 17M are connected to input terminals 23L, 23R, and 23M of the audio processing circuit 19, and terrestrial broadcast audio signals (hereinafter referred to as terrestrial audio signals) are output to these input terminals 23L, 23R, and 23M. It is supposed to be done.

Further, the satellite broadcast input terminal 13 connected to the satellite broadcast antenna 12 is connected to a satellite broadcast reception tuner circuit 24. Demodulates the video and audio signals necessary to normalize the signals to satellite broadcasting,
On the other hand, if the satellite broadcasting is not scrambled, the satellite broadcasting is demodulated into a video signal and a stereo audio signal and outputted to one input side of the switching circuit 25.

The other input side of the switching circuit 25 is also connected to the descrambler 11 via descrambler input terminals 9■, 9L, and 9R, and is connected to the satellite signal from the descrambler 11 and from the satellite broadcast reception tuner circuit 24. The output is switched between normalized satellite signals and normalized satellite signals. The output side of this switching circuit 25 is connected to one input side of a switching circuit 26 whose other input side is connected to external input terminals 8■, 8L, and 8R.
6 switches between an external signal from the video equipment 27 and a satellite signal from the switching circuit 25 and outputs the signal.

The above switching circuit 26 has an output terminal 2 that outputs a video signal.
6-' and an output terminal 26L that outputs a stereo audio signal.
・The output terminal 26V is connected to the video output terminal 1■ via the switching circuit 29, and is also connected to the input side of the video recording and reproducing circuit B22 via the switching circuit 21. ing. In addition, the output terminal 26 of the switching circuit 26
L.26R is the audio processing circuit 19 as shown in FIG.
The input terminals 28L and 28R are connected to the input terminals 28L and 28R, and audio signals of satellite broadcasting or external signals (hereinafter referred to as satellite/external audio signals) are output to these input terminals 28L and 28R.

The above-mentioned input terminal 28L is configured to receive the main channel signal of the satellite/external audio signal converted into a stereo signal, while the input terminal 28R is configured to receive the main channel signal of the satellite/external audio signal converted into a stereo signal. The sub channel signal is now input. In addition, similar to these one set of input terminals 28L and 28R, one set of input terminals 23
The main channel signal and sub-channel signal of the stereo signal terrestrial audio signal are inputted to L and 23R from the output terminals 17L and 17R, and the monaural signal from the output terminal 17M is input to the input terminal 23M. terrestrial audio signals are input.

Input terminal 28L into which the above satellite/external audio signal is input
・28R and input terminal 23L where terrestrial audio signals are input
- 23R is connected to each C input terminal and each input terminal of the satellite ground switching circuit 31, which has two sets of two-man-operated switch sections, a C input terminal and a B input terminal.

The satellite ground switching circuit 31 is connected to the control input terminal 19.
The H-level control signal 1 inputted through a connects each C input terminal and the output terminals 31L and 31R, while the L-level control signal 1 connects each input terminal and output terminal 31.
It is designed to connect L and 31R.

In addition, the above input terminals 28L and 28R are connected to a monitor switching circuit 320@a input terminal ↓, which will be described later.
A satellite/external audio signal serving as a monitor signal is output to the monitor switching circuit 32. Furthermore, the input terminals 28L and 28R are connected to the input side of a mixing circuit 30 that mixes and outputs the two input signals, and the mixing circuit 30 has an output side that is connected to a monaural signal switching circuit 33 that is powered by three people. is connected to the a-side input terminal of. The mixing circuit 30 is configured to output a mixed signal of the main channel signal and the sub-channel signal of the external audio signal to the above-mentioned C input terminal.

In addition to the C input terminal, the monaural signal switching circuit 33 has a b input terminal and a C input terminal, and the input terminal 28L is connected to the b input terminal, and the input terminal 28L is connected to the b input terminal. The main channel signal is now input. Further, an input terminal 23M is connected to the C input terminal of the monaural signal switching circuit 33.
A monaural terrestrial audio signal is input through M. Furthermore, this monaural signal switching circuit 3
3, so that control signal 1 and control signal 2 are input ↓
It's happening. Then, this monaural signal switching circuit 33
In this case, the C input terminal and the output terminal 33M are connected with the H level control signal 1 and the L level control signal 2, and the B input terminal is connected with the H level control signal 1 and the H level control signal 2. and the output terminal 33M are connected, and the C input terminal and the output terminal 33M are connected by the L level control signal 1 regardless of the level of the control signal 3.

The monaural signal switching circuit 33 described above has an output terminal 33M connected to the recording amplifier 38 of the recording/reproducing circuit 35.

This recording amplifier 38 is connected to a fixed magnetic node 39, and is configured to record a monaural signal from an output terminal 33M on a monaural track 40M of the magnetic tape 40 shown in FIG. In addition, the recording/reproducing circuit 35 includes a pair of recording amplifiers 36L and 3 together with the recording amplifier 38 described above.
6R, each recording amplifier 36L, 36R,
The respective output terminals 31L and 31R of the satellite ground switching circuit 31 are connected. And these recording amplifiers 36L・3
6R is connected to a rotary magnetic head 44 via FM modulators 42L and 42R, and records the stereo/external audio signal on the stereo track 4O3 of the magnetic tape 40 in FIG. It looks like this.

The above-mentioned rotating magnetic head 44 and fixed magnetic head 39 perform both recording and reproduction, and the rotating magnetic head 44 is connected to FM demodulators 43L and 43R.
It is connected to the reproducing amplifiers 37L and 37R via , and is also connected to a HiFi detection circuit 45 that detects whether or not the FM modulation signal is being reproduced and outputs a HiFi detection signal. And, the reproduction amplifiers 37L and 37R have magnetic
Stereo track 40S in Figure 2 played back at Nodo 44
The signals are demodulated by FM demodulators 43L and 43R and manually output as stereo reproduction signals. on the other hand,
The fixed magnetic head 39 is connected to a reproduction amplifier 41, and the signal of the monaural track 40M shown in FIG. 2 is input to the reproduction amplifier 41 as a monaural reproduction signal reproduced by the magnetic throat 39. It has become.

The output side of each of the above-described reproduction amplifiers 37L, 37R, and 41 is connected to the recording/reproduction switching circuit 46. This recording/reproduction switching circuit 46 has two sets of three-man-operated switch parts, and the output terminals 31L and 31R of the satellite ground switching circuit 31 are connected to both a input terminals, and the output terminals 31L and 31R of the satellite ground switching circuit 31 are selected. satellite/external audio signals or terrestrial audio signals are input. In addition, the recording/reproducing switching circuit 4
The above-mentioned playback amplifiers 37L and 37 are connected to both input terminals of 6.
R is connected, and a stereo playback signal is input through these playback amplifiers 37L and 37R.
A reproduction amplifier 41 is connected to both C input terminals, and a monaural reproduction signal is inputted via the reproduction amplifier 41.

The recording/reproduction switching circuit 46 is configured to receive at least the HiFi detection signal from the HiFi detection circuit 45 and the E-E signal output during recording, and the a input terminal is connected to the E-E signal. When the -E signal is input, it is connected to the S: output terminals 46L and 46R. In addition, the b input terminal is connected to the output terminals 46L and 46R when a HiFi detection signal is input during playback, and the C input terminal is connected to the HiFi detection signal during playback.
When i is not detected, it is connected to the output terminals 46L and 46R.

The above-mentioned recording/reproduction switching circuit 46 converts the signals inputted to each input terminal 1 into output terminals 46L and 46R as recording/reproduction signals.
These output terminals 46
L.46R is connected to the b input terminal of the monitor switching circuit 32. This monitor switching circuit 32 has two sets of two-man-operated switch sections consisting of an a input terminal connected to the input terminals 28L and 28R of the above-mentioned audio processing circuit 19 and the above-mentioned b input terminal. Signal 3 is input to this monitor switching circuit 32.
When the level control signal 3 is input, the a input terminal and the output terminals 32L and 32R are connected to each other, while when the L level control signal 2 is input, the b input terminal and the output terminal 321.・It is designed to connect with 32R.

Furthermore, the monitor switching circuit 32 described above has an output terminal 32L.
・32R is connected to the output switching circuit 47. This output switching circuit 47 has two sets of three-man power switch/notch sections, and both a input terminals are connected to the output terminals 32L and 32R of the monitor switching circuit 32, respectively. Also,
Both input terminals of the output switching circuit 47 are connected to the output terminal 32L of the monitor switching circuit 32, and both C input terminals of the output switching circuit 47 are connected to the output terminal 32R of the monitor switching circuit 32. There is. An output switching signal is input to this output switching circuit 47, and this output switching signal is transmitted to the a input terminal, the b input terminal,
and C input terminal and output terminal 47L of output switching circuit 47
- By switching the connection state with 47R, the monitor signal and recording/playback signal output from the monitor switching circuit 32 can be formed into three types of output signals: a stereo audio signal, a main channel signal, and a sub channel signal. ing.

In the output switching circuit 47 described above, output terminals 47L and 47R are connected to output terminals 2OL and 2OR, and these output terminals 2OL and 2OR are connected to audio output terminals IR and IL that are connected to the television 2 in FIG. It is connected to the. The output terminals 47L and 47R of the output switching circuit 47 are also connected to the input side of a mixing circuit 480 that mixes two input signals and outputs the mixed signal. Further, the output of this mixing circuit 48 is connected to the output terminal 20M of the audio processing circuit 19, and is connected to the television 2 via a switching circuit 18 including a modulator 18C that converts it into a terrestrial broadcast signal in FIG. .

In the above configuration, the operation of the audio recording/reproducing switching circuit will be explained below.

First, as shown in FIG. 3, a VTRI with a built-in audio processing circuit 19 receives satellite broadcasts from the satellite broadcast antenna 12, terrestrial broadcasts from the terrestrial broadcast antenna 14, and external broadcasts from the video equipment 27. will be input.

The above satellite broadcasting is input to the satellite broadcasting receiving tuner circuit 24 via the satellite broadcasting input terminal 13, and is demodulated into a video signal and a stereo audio signal by this satellite broadcasting receiving tuner circuit 24, and then switched. It will be output to the circuit 25.

In addition, the satellite signal is outputted from the satellite broadcast reception tuner circuit 24 to the descrambler 11 via the descramble output terminal 10V/10A, and is descrambled by the descrambler 11 to form a video signal and a stereo audio signal. is normalized and output to the switching circuit 25 via the descramble input terminals 9 - 9L and 9R. Then, the switching circuit 25 to which both signals are input from the descrambler 11 and the satellite broadcast reception tuner circuit 24 is switched depending on the determination result of whether the satellite signal is encrypted or not, and the normal video signal and stereo audio signal are switched. It will be output to the switching circuit 26.

A video signal and a stereo audio signal, which are external signals from the video equipment 27, are also input to the switching circuit 26, and the satellite signal and the external signal are switched and outputted by the switching circuit 26. . Then, the switching circuit 26
The video signal selected is input to the video recording/reproducing circuit 22 via the switching circuit 21 and recorded therein, and is also output to the television 2 via the switching circuit 29. On the other hand, the stereo audio signal selected by the switching circuit 26 is sent to the input terminal 28 of the audio processing circuit 19 as a satellite/external audio signal.
It will be output to L/28R.

Furthermore, the terrestrial broadcasting inputted from the terrestrial broadcasting antenna 14 is inputted to the terrestrial broadcasting reception tuner circuit 17 via the terrestrial broadcasting input terminal 15, and is also inputted to the television 2 via the switching circuit 18. . Terrestrial broadcasts input to the terrestrial broadcast reception tuner circuit 17 are demodulated into a video signal and a terrestrial audio signal consisting of a stereo audio signal or a monaural audio signal. It will be input to the processing circuit 22. - way,
The terrestrial audio signals are output from the output terminals 17L, 17R, and 17M to the input terminals 23L, 23R, and 23M of the audio processing circuit 19.

In this way, each input terminal 28L, 2 of the audio processing circuit 19
8R・23L・23R-23M! : is the satellite broadcasting antenna 12 or terrestrial broadcasting antenna 1 connected to the VTRI.
4. Each signal from the video equipment 27 is inputted, and the input terminal 28L receives the main channel signal of the satellite/external audio signal, while the input terminal 28R receives the satellite/external audio signal. The sub-channel signal of the signal is input. Further, the main channel signal of the terrestrial audio signal is input to the input terminal 23L, while the sub channel signal of the terrestrial audio signal is input to the input terminal 23R. 23M is configured to receive a monaural audio signal as a terrestrial audio signal.

The satellite/external audio signals input to the input terminals 28L and 28R are transmitted to the satellite ground switching circuit 3 as shown in FIG.
1, the mixing circuit 30, the b input terminal of the monaural signal switching circuit 33, and the a input terminal of the monitor switching circuit 32. In addition, the input terminal 23
Regarding the terrestrial audio signals input to L, 23R, and 23M, the stereo audio signal is input to each input terminal of the satellite ground switching circuit 31, while the monaural audio signal is input to the C input terminal of the monaural signal switching circuit 33. That will happen. Further, the satellite/external audio signal input to the mixing circuit 30 is converted into a mixed signal of the main channel signal and the sub-channel signal, and then input to the a input terminal of the monaural signal switching circuit 33. .

As a result, a stereo audio signal consisting of a satellite/external audio signal and a terrestrial audio signal is input to the satellite ground switching circuit 31, and both of these signals are selected by switching the switch section using the control signal 1. Output terminal 31L/31
This is what is output from R. Furthermore, a mixed signal of the satellite/external audio signal, a main channel signal of the satellite/external audio signal, and a monaural audio signal of the terrestrial audio signal are input to the monaural signal switching circuit 33, and these signals are as follows. It is selected by switching the switch section using control signals 1 and 2 and is outputted from the monaural signal switching circuit 33.

Further, the control signal 3 is configured to switch the switch section of the monitor switching circuit 32.
Satellite/external audio signals serving as monitor signals from input terminals 28L and 28R are input to each input terminal a of 2. On the other hand, the stereo audio signal from the satellite ground switching circuit 31 and the stereo playback signal and monaural audio signal from the recording and playback circuit 35 are input to each input terminal of the monitor switching circuit 32 via the recording and playback switching circuit 46. is entered as .

The above satellite ground switching circuit 31 and monaural signal switching circuit 3
3, and a control signal 1 input to the monitor switching circuit 32.
- As shown in Table 1, 2 and 3 enable the selection of six types of modes by combining the H level and L level.

Table 1 The input side of the logic reproduction circuit 35 is divided into the input side and the monitor switching circuit, and the input side of the logic reproduction circuit 350 is
Control signal 1 at H level and control signal 2 at L level are input to control input terminals 19a and 19b. The satellite ground switching circuit 31 to which the H level control type signal 1 is input connects the a input terminal and the output terminals 31L and 31R, while the monaural signal switching circuit 33 controls the H level control. Signal 1 and L level control signal 2
This brings the a input terminal and the output terminal 33M into a connected state.

Thereby, the satellite/external audio signal is manually input to the recording/reproducing circuit 35 via the satellite ground switching circuit 31, and is recorded in stereo by the magnetic throat 44. Further, the main channel signal and sub-channel signal of the satellite/external audio signal mentioned above are mixed in a mixing circuit 30 to become a monaural audio signal, and then inputted to a recording/reproducing circuit 35 via a monaural signal switching circuit 33. , the magnetic head 39 records monaural information.

Next, in the case of the dual audio satellite mode, the H level control signal 1 and the H level control signal 2 are sent to the control input terminal 19.
It will be input to a and 19b. Then, the satellite ground switching circuit 3 to which the H level control signal 1 is input is a
The input terminal and the output terminal 3] L and 31R are connected, while the monaural signal switching circuit 33 connects the b input terminal and the output terminal 33M with the H level control signal l and the H level control signal 2. will be in a connected state.

As a result, the satellite/external audio signal is input to the recording/reproducing circuit 35 via the satellite ground switching circuit 31, and is recorded in stereo by the magnetic head 44. Further, the above-mentioned satellite/external audio signal is converted into a monaural audio signal from the main channel signal by the monaural signal switching circuit 33, inputted to the recording/reproducing circuit 35L, and recorded monaurally by the magnetic head 39.

In addition, in the case of terrestrial broadcasting mode, the L level control signal 1 and the arbitrary level control signal 2 are input to the control input terminal 19.
It will be man-powered by A and 19B. The satellite ground switching circuit 31 to which the L level control signal 1 is input is b
While the input terminal and the output terminals 31L and 31R are connected, the monaural signal switching circuit 33 connects the C input terminal and the output terminal 33M with the arbitrary rail control signal 2 and the L level control signal 3. The connection status will be changed.

As a result, the terrestrial audio signal is input to the recording/reproducing circuit 35 via the satellite terrestrial switching circuit 31, and is recorded to the magnetic field in stereo L/O at 144, while the monaural audio signal of the terrestrial broadcast is The signal is input to the recording/reproducing circuit 35 via the monaural signal switching circuit 33, and is recorded monaurally by the magnetic head 39.

At this time, an EE signal indicating that recording is in progress is input to the recording/reproducing switching circuit 46, and the a input terminal is connected to the output terminals 46L and 46R of the recording/reproducing switching circuit 46. ing. Therefore, the satellite/external audio signal output from the satellite ground switching circuit 31 is output to the output switching circuit 47 via the recording/playback switching circuit 46 and the monitor switching circuit 32 as well as being recorded by the recording/playback circuit 35. Become. Then, this satellite/external audio signal is outputted from the output terminals 2OL and 2OR to the television 2 in FIG. 3 via the output switching circuit 47. This makes it possible to output the satellite/external audio signal being recorded to the television 2 without recording the satellite/external audio signal.

On the other hand, in the terrestrial broadcasting mode, the stereo audio signal of the terrestrial broadcasting signal is recorded by the recording/reproducing circuit 35 and is output from the output terminals 20L/2OR via the recording/reproducing switching circuit 46, the monitor switching circuit 32, and the output switching circuit 47. It will be output to the television 2 shown in FIG. Thereby, when the terrestrial broadcasting mode is executed, it becomes possible to output the terrestrial audio signal being recorded to the television 2 without recording the terrestrial audio signal.

In addition, in the case of the playback mode, the stereo playback signal and the monaural playback signal from the recording and playback circuit 35 are transmitted to the recording and playback switching circuit 46 and the monitor switching circuit 3 regardless of the control signals 1 and 2.
2, and the output terminal 2OL/2 through the output switching circuit 47.
It will be output from 2OR to TV 2 in Figure 3,
When the playback mode is executed, it becomes possible to output a stereo playback signal or a monaural playback signal to the television 2.

In addition, in the case of the ground recording satellite monitor mode and the playback satellite monitor mode, the H level control signal 3 is sent to the control input terminal 1.
It will be input at 9c. The monitor switching circuit 32 to which the H level control signal 2 is input connects the a input terminal and the output terminals 32L and 32R. As a result, the monitor switching circuit 32 switches the input terminal 28
Output switching circuit 4 for satellite/external audio signals from L/28R
7 from the output terminals 20L and 2OR to the TV 2 in Figure 3, and when each satellite monitor mode is executed, the satellite/external audio signal is output to the TV 2 during ground recording and playback. becomes possible.

In this way, the audio recording/reproducing switching circuit of this embodiment has the monitor switching circuit 32 built into the audio processing circuit 19, and the input terminal 28.
Since the satellite/external audio signals input to a and 28b are input to the a input terminal of the monitor switching circuit 32, the audio processing circuit 1 with the built-in monitor switching circuit 32
It is no longer necessary to newly install an input terminal for inputting satellite/external audio signals to 9.

Furthermore, the monitor switching circuit 32 is provided between the signal path of the recording/reproducing circuit 35 and the output switching circuit 47, so that even when the number of input contacts is reduced from the conventional four-manpower to two-manpower,
By switching the output switching circuit 47, the signal format during satellite monitoring can be switched to three types of output signals: a stereo signal, a main channel signal, and a sub channel signal.

Therefore, by combining the monitor switching circuit 32 with the three-man powered output switching circuit 47, it is possible to form the same signal format as the conventional one by simply adding a single control signal 3.

Therefore, the audio recording/reproducing switching circuit is capable of incorporating all the circuits into the audio processing circuit 19 while suppressing the number of terminals of the audio processing circuit 19 to the necessary minimum.
It has become possible to convert the chip into an IC, which in turn has made it possible to downsize the mounting board and the like.

[Effects of the Invention] As described above, the audio recording/reproducing switching circuit according to the present invention can switch and output the monitor signal and the recording/reproducing signal consisting of the main channel signal and the sub-channel signal into three types of audio signals, respectively. The audio recording/reproducing switching circuit outputs audio signals of each of the above formats from one set of output terminals, and the monitor signal is input from one input terminal of the two sets of input terminals, and the above-mentioned monitor signal is input from one input terminal of the two sets of input terminals. It has a monitor switching circuit that can switch and output a monitor signal and a recording/playback signal, and an output switching circuit that can switch the signal output from the monitor switching circuit into three types of audio signals and output them to an output terminal. This is a configuration where there is

As a result, the monitor switching circuit can be switched by a single control signal because it is operated by two people, and the monitor signal input to the monitor switching circuit can be input from one input terminal of two sets of input terminals. This makes it possible to reduce the number of terminals to the necessary minimum, and furthermore, since the monitor switching circuit and single output switching circuit for outputting each signal type are incorporated, it is possible to reduce the number of terminals to the necessary minimum. This has the effect of making it possible to use an IC, which in turn makes it possible to downsize the mounting board and the like.

[Brief explanation of the drawing]

1 to 3 show one embodiment of the present invention. FIG. 1 is a block diagram of the audio recording/reproducing switching circuit. FIG. 2 is an explanatory diagram showing the state of signal recording on the magnetic tape. FIG. 3 is a block diagram of a VTR equipped with an audio recording/reproducing switching circuit. 4 and 5 show conventional examples. FIG. 4 is a block diagram of the audio recording/reproducing switching circuit. FIG. 5 is a block diagram of the audio recording/reproducing switching circuit. ] is VTR317 is terrestrial broadcast reception tuner circuit, 1
9 is an audio processing circuit, 19a and 19b are control input terminals,
2OL, 2OR, 20M are output terminals, 26 is a switching circuit,
23L, 23R, 23M, 28L, 28R are input terminals,
30 is a mixing circuit, 31 is a satellite ground switching circuit, 321 is a monitor switching circuit, 33 is a monaural signal switching circuit, 34 is an AND circuit, 35 is a recording/reproducing circuit, 39 and 44 are magnetic to/node, and 45 is a HiFi 46 is a recording/reproduction switching circuit, 47 is an output switching circuit, 48 is a mixing circuit, and 49 is a monaural signal switching circuit.

Claims (1)

[Claims] 1. A monitor signal and a recording/playback signal consisting of a main channel signal and a sub-channel signal can each be switched and outputted into three types of audio signals, and the audio signals of each of the above formats can be output as one set. An audio recording/reproducing switching circuit outputting from a terminal, wherein the monitor signal is input from one input terminal of two sets of input terminals, and the circuit is capable of switching and outputting the monitor signal and the recording/reproducing signal. An audio recording/reproducing switching circuit comprising a monitor switching circuit and an output switching circuit capable of switching a signal output from the monitor switching circuit into three types of audio signals and outputting the signals to an output terminal.