JPS5928504Y2 - magnetic recording and playback device - Google Patents

Description

[Detailed description of the invention] This invention is a magnetic recording and reproducing device (such as a magnetic recording and reproducing device equipped with a Dolby type noise reduction circuit, for example, which is useful for microphones, etc.) to reduce hiss noise that occurs when playing back signals recorded on magnetic tape. It is an object of the present invention to provide an excellent magnetic recording and reproducing device that can solve all the various problems that occur when mixing mixed signals.

Various types of noise reduction circuits have been developed to reduce general hiss noise.

One of the most famous is the Dolby one-type noise reduction circuit, whose main feature is to lower the level of high frequencies during recording.

By the way, in the case of a magnetic recording/reproducing apparatus equipped with this type of noise reduction circuit (in which microphone mixing is possible), it is usually constructed as shown in FIG.

That is, in Fig. 1, 1 is a playback head, 2 is an equalizer amplifier that amplifies the output of the playback head 1, 3 is an input terminal to which a signal obtained from a microphone or the like is applied, and 4 is an input terminal to which 3σ is applied. an amplifier that amplifies the signal; 5;
6 is a resistor, 7 is a switch, 8 is a noise reduction circuit, 9 is a switch for turning on and off the noise reduction function of the noise reduction circuit 8;
10 is an output terminal.

Therefore, even in the conventional magnetic recording and playback system shown in FIG. , the function of the noise reduction circuit 3 can be turned on and off by turning it off.

However, in the conventional magnetic recording/playback device shown in FIG. 1, switches 7 and 9 are provided independently, so it is possible to turn on switch 1 while switch 9 is on, and in this case, the microphone The high frequency range of the signal obtained by the reproduction head 1 is attenuated together with the signal obtained by the reproduction head 1, so that the signal obtained by the microphone etc.
This results in unnecessary distortion of the obtained signal, which is extremely inconvenient.

Therefore, the user must be careful to turn off the switch 9 every time the switch 7 is turned on, which is very inconvenient for the user.

This proposal eliminates the above-mentioned conventional drawbacks,
The structure is such that the signal obtained by a microphone or the like appears directly at the output terminal without any reduction in high frequencies.

That is, the magnetic recording and reproducing device of the present invention has a switch 9 that turns on and off the function of the noise reduction circuit 8 and a switch 7 that turns on and off mixing, as shown in FIGS. 2 and 3, in conjunction with each other. The configuration is such that the function of the noise reduction circuit 8 is automatically turned off whenever mixing is turned on.

Hereinafter, FIGS. 2 and 3 will be explained in detail.

In the embodiments shown in FIGS. 2 and 3, the switch 7.
As 9, a changeover switch having three fixed contacts a, b, and c is used.

Now, if switch 7゜9 is inserted into fixed contact a, then
Both the mixing and noise reduction circuit 8 functions are off, and only the signal obtained by the playback head 11 appears at the output terminal 10 without noise reduction.

When the switch 7.9 is turned on to the fixed contact, the mixing is turned off and the function of the noise reduction circuit 8 is turned on, so that only the signal obtained by the playback head 1 is noise-reduced and appears at the output terminal 10. .

When the switch 7.9 is connected to the fixed contact C, the mixing is turned on and the function of the noise reduction circuit 8 is turned off, so that the signal applied to the input terminal 3 is mixed with the signal obtained by the playback head 1. appears at the output terminal 10 without noise reduction.

In this way, according to the above embodiment, it is possible to guide only the signal obtained by the playback head 1 to the output terminal with or without noise reduction, and also to automatically reduce the noise when performing microphone mixing. The signal can be guided to the output terminal without being reduced.

Therefore, the above-mentioned embodiment does not require any troublesome operations as in the prior art, and is extremely advantageous in practice.

According to the embodiment, when microphone mixing is performed, there is no noise reduction function, but since the overall signal component becomes larger due to microphone mixing, noise such as hiss noise does not become a problem for the auditory sense.

As is clear from the above embodiments, the magnetic recording and reproducing device of the present invention does not require complicated operations like conventional ones when mixing microphones, and can always obtain excellent acoustic effects, which is extremely advantageous in practice. It is.

[Brief explanation of the drawing]

Figure 1 is a schematic electrical wiring diagram of a conventional magnetic recording and playback device.
FIGS. 2 and 3 are schematic electrical connection diagrams of the embodiments of the present invention, respectively. 1... Playback head, 2, 4... Amplifier, 3... Input terminal, 5, 6... Resistor,
7, 9...Switch, 8...Noise reduction circuit, 10...Output terminal.

Claims (1)

[Scope of utility model registration request] a noise reduction circuit for reducing hiss noise generated during reproduction of a signal recorded on a magnetic tape; a first changeover switch for turning on and off the operation of the noise reduction circuit;
a second changeover switch that is provided upstream of the noise reduction circuit and mixes the signal obtained by a microphone or the like with the reproduction signal of the magnetic tape, and the first and second changeover switches are switched when the noise reduction circuit is off. , a magnetic recording and reproducing device characterized in that the magnetic recording and reproducing device is capable of mixing and is interlocked with each other so that mixing is disabled when the noise reduction circuit is on.