JPS60140502A - Magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To reduce the number of parts of an audio processing circuit and to obtain a low-cost magnetic recording and reproducing device by omitting audio recording and reproducing circuits for the middle speed mode. CONSTITUTION:An equalizer circuit for recording of the two-hour mode is used for recording of the four-hour mode. In this state, audio signals are inputted and are amplified by a mike amplifier 1 and are amplified by a line amplifier 2 and are inputted to a recording equalizer amplifier 9. In the recording equalizer amplifier 9, inputted signals are biased in the equalizer circuit of the two-hour mode by a frequency characteristic for the two-hour mode and are outputted to a recording head 6 and are recorded on a magnetic tape. At a reproducing time, the mode of reproduced signals is detected by a mode detecting circuit and is given to a mode switching circuit 5'. An equalizer circuit of the six-hour mode out of equalizer circuits incorporated in a regenerative equalizer amplifier 8 is made operatable in accordance with this mode. That is, the regenerative equalizer amplifier amplifies reproduced signals so that they have a frequency characteristic of the six-hour mode, and they are amplified by the line amplifier 2 and are outputted as audio signals.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a magnetic recording/reproducing device W capable of switching between a low speed mode, a medium speed mode, and a high speed mode, and particularly relates to an improvement in the audio processing circuit of the device. It is.

[Prior Art] Conventionally, magnetic recording/recording/reproducing main devices divide the running speed of the recording medium into multiple modes in order to achieve the desired recording/reproduction.
Many of them allow you to switch between different modes. For example, in the VH8 type magnetic recording and reproducing apparatus used in the United States and other countries, a magnetic recording and reproducing apparatus that can switch between a 2-hour mode, a 4-hour mode, and a 6-hour mode is popular.

Such a magnetic recording/reproducing device is provided with a circuit for recording and a circuit for reproducing audio signals for each mode. FIG. 1 is a block diagram showing the circuit configuration.

In FIG. 1, 1 is a microphone amplifier, 2 is a riser amplifier, 3 is a reproduction equalizer amplifier, 4 is a recording equalizer amplifier, and 5 is a mode switching circuit.

The operation in FIG. 1 is as follows. At the time of recording, a mode changeover switch provided on the main body of the magnetic recording/reproducing apparatus is operated to select a desired recording mode from among the 2-hour mode, 4-hour mode, and 6-hour mode. In response to this selection, the mode switching circuit 5 enables the equalizer circuit of the selected mode among the equalizer circuits built into the recording equalizer amplifier 4. For example, when the 2-hour mode is selected, the 2-hour mode equalizer circuit (2H mode EQ) is made operable.

In this state, an audio signal is input, amplified by the microphone amplifier 1, amplified by the line amplifier 2, and input to the recording equalizer amplifier 4. The recording equalizer amplifier 4 sends the recording signal output amplified to match the selected two-hour mode to the recording head 6, and records the audio signal on a magnetic tape (not shown).

During playback, the mode 1- at the time of recording is automatically detected from the nitric tape by the mode detection circuit, and the detection signal of A is detected as -.
[- is given to the cutting circuit 5. In response to the detected mode, the mode switching circuit 5 enables the equalizer of a predetermined mode from the equalizer circuit built in the reproduction equalizer amplifier 3. For example, in the case of the 2R mode, the 2-hour mode equalizer (2H mode EQ) is enabled. In this state, the reproduction Hen door extracts the signal recorded on the magnetic chip and supplies it to the reproduction enabler amplifier. Then, the reproduction equalizer amplifier 3 sets the frequency characteristics of the reproduction signal to frequency and number characteristics suitable for the 2-hour mode, and outputs the signal to the line amplifier 2.

The reproduced signal is then amplified by the line amplifier '2, and an audio signal is output.

The audio processing circuit of a conventional magnetic recording/reproducing device is as shown above, so each equalizer circuit built into the recording equalizer amplifier 4 and the reproduction equalizer amplifier 3 is required for each mode. The disadvantages are that it has a large number of components and its circuit configuration is complex.

[Summary of the Invention 1 Therefore, the main object of the present invention is to provide a low speed mode (for example, 6 hour mode) and a medium speed mode (for example, 411 hour mode).
In a magnetic recording and reproducing device capable of switching between a high speed mode (for example, 2-hour mode) and a high-speed mode (for example, 2-hour mode), the audio recording circuit or playback circuit in the medium-speed mode is used to record g-voice when used in the low-speed mode or high-speed mode. By using a magnetic recording and reproducing device that is dual-purpose circuit or reproducing circuit, and omitting the audio recording circuit and reproducing circuit in medium-speed mode, the number of components in the audio processing circuit is reduced and the cost of magnetic recording is low. The purpose of the present invention is to provide a playback device.

[Embodiment of the Invention] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

FIG. 2 is a block diagram showing an audio processing circuit according to an embodiment of the present invention. In the figure, 8 is a reproduction equalizer amplifier, and 9 is a recording equalizer amplifier. As shown in the figure, the equalizer circuits used internally in both the playback equalizer amplifier 8 and the recording equalizer amplifier 9 are a 2-hour mode equalizer amplifier and a 6-hour mode equalizer amplifier, and a 4-hour mode equalizer amplifier. has been deleted. This is one of the features of this embodiment. Further, the mode switching circuit vli5' is configured to operate in a manner suitable for this embodiment. Note that the other circuits are the same as the conventional example shown in FIG.
Identical parts are given the same number 1 and their explanations are omitted.

Next, the operation of the circuit shown in FIG. 2 will be explained.

In the circuit shown in FIG. 2, the operations in the 2-hour mode and 6-hour mode are similar to those of the conventional circuit for both recording and reproduction.

In the 4-hour mode, this circuit operates as follows. First, during recording, in response to the selection of the 4-hour mode, a signal is output from the mode switching circuit 5-, and 21I of the equalizer circuits built in the recording equalizer amplifier 9 are output.
The 2-H mode equalizer circuit (2-H mode EQ) is selected to be ready for operation. That is, when recording in the 4-hour mode, the equalizer circuit used in recording in the 2-hour mode is used. In this state, an audio signal is input,
The signal is amplified by a microphone amplifier 1, amplified by a line amplifier 2, and inputted to a recording equalizer amplifier 9.

In the recording equalizer amplifier 9, the input signal is biased with the frequency characteristics in the 2-hour mode by a 2-hour mode equalizer circuit, and outputted to the recording head 6. In other words,
The recording signal is output to the recording head 6 biased to the frequency characteristics in the 2-hour mode, and is recorded on a magnetic tape (not shown).

Next, during reproduction, a mode detection circuit (not shown) detects the mode of the reproduced signal (in this case, the 48! interval mode), and provides the detected signal to the mode switching circuit 5-. In response, the mode switching circuit 5- enables the 6-hour mode equalizer circuit among the equalizer circuits built in the reproduction equalizer amplifier 8. In this embodiment, a 6-hour mode equalizer circuit is used when reproducing a 4-hour mode audio signal. When the signal recorded on the magnetic tape is extracted by the playback head 7 and given to the playback equalizer amplifier 8, the playback equalizer amplifier amplifies the playback signal so that it has the frequency characteristics of the 6-hour mode, and outputs it to the line amplifier 2. . The signal is then amplified by the line amplifier 2 and output as an audio signal.

As in this example, even if the recording equalizer amplifier used in the 2-hour mode is used instead of the recording equalizer amplifier used in the 2-hour mode for recording in the 4-hour mode, and the reproduction equalizer circuit used in the 6-hour mode is used instead during playback,
It has been experimentally confirmed that the audio output signal characteristics are only slightly degraded and there is no problem in practical use.

In the above embodiment, the recording circuit (equalizer circuit) and reproduction circuit (equalizer circuit) in the 4-hour mode are
Recording circuit (equalizer circuit) in 2-hour mode and playback circuit (equalizer circuit) in 6-hour mode, respectively.
However, the present invention is not limited to this, and the recording circuit for the 4-hour mode can be replaced by the recording circuit for the 6-hour mode or the recording circuit for the 2-hour mode 1, and the playback circuit for the 4-hour mode can be replaced by the 6-hour recording circuit. A regeneration circuit for time mode or a regeneration circuit for 2fI mode may be used instead.

In the description of each of the above embodiments, a VH8 type magnetic recording and reproducing device that can switch between 2-hour mode, 4-hour mode, and 6-hour mode has been described.
It should be pointed out that the present invention can also be applied to other magnetic recording and reproducing devices, such as β-type magnetic recording and reproducing devices.

[Effects of the Invention] As described above, according to the present invention, since the audio recording circuit or reproducing circuit in the medium speed mode is also used as the audio recording circuit or reproducing circuit in other modes, the recording The number of parts in the circuit or regeneration circuit is reduced, resulting in a low-cost product.

[Brief explanation of the drawing]

FIG. 1 is a configuration block diagram of an audio processing circuit of a conventional magnetic recording/reproducing device. FIG. 2 is a block diagram of the configuration of an audio processing circuit according to an embodiment of the present invention. In the figure, 3.8 is a reproduction equalizer amplifier, 4.9 is a recording equalizer amplifier, and 5.5- is a mode switching circuit. Note that the same reference numerals in the figures indicate the same or corresponding parts. Teenage spit man big rock Masu male

Claims (3)

[Claims] (1) A low-speed mode in which the recording medium is run at a relatively low speed in order to increase the recording/reproducing density, and a high-speed mode in which the recording medium is run in a relatively related manner in order to make the recorded and reproduced contents clearer. and a medium-speed mode in which the recording medium runs at a predetermined speed between the low-speed mode and the high-speed mode.
A magnetic recording/reproducing device characterized in that the device is configured to double as an audio recording circuit or a reproducing circuit used in the low speed mode or high speed mode. (2) The magnetic recording and reproducing device is a Vl-1s type device, and the low speed mode, medium speed mode, and high speed mode are a 6-hour mode, a 4-hour mode, and a 2-hour mode, respectively. A magnetic recording/reproducing device according to claim 1. (3) The audio recording circuit in the 4-hour mode is also used as the audio recording circuit in the 2-hour mode, and the audio reproducing circuit in the 4-hour mode is also used as the audio reproducing circuit in the 6-hour mode. A magnetic recording and reproducing apparatus according to claim 2, characterized in that: