JPS594763B2 - Linear AC signal transmission device - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a linear AC signal transmission device such as a magnetic head, transformer, inductance, etc. using a ferrite core.
In particular, it is designed to eliminate distortion of the transmitted signal.

Conventionally, when a signal recorded on a magnetic tape is reproduced by a magnetic head using a ferrite core, the sound is hard and harsh, causing a problem in terms of sound quality as high-fidelity (HiFi).

This is because the B-H characteristic of the ferrite core has large distortion at a level slightly above the initial permeability, as shown in curve 1 in Figure 1, and when the input signal has a waveform as shown in Figure 1, the magnetic It is thought that this is because the signal obtained on the output side of the head is distorted due to distortion near this initial magnetic permeability, as shown by curve 3 in FIG. 5 In view of the above, the present invention is designed to prevent signal distortion due to distortion near the initial permeability of the B-H characteristic of the ferrite core in linear AC signal transmission devices such as magnetic heads, transformers, and inductances that use a ferrite core. This is to prevent this from occurring.

10 Hereinafter, one embodiment of the linear AC signal transmission device of the present invention will be explained with reference to FIG.

FIG. 2 shows an example of use in the magnetic head of the present invention.
In Fig. 2, numeral 4 indicates a reproducing magnetic head using a ferrite core, one end of a detection coil wound around this ferrite core is grounded, and the other end of this detection coil is connected to a low frequency pass. Connect to the input side of filter 5. In this example, an AC bias signal is supplied to the reproducing magnetic head 4. That is, in FIG. 2, reference numeral 6 indicates an AC bias signal generator, and the output signal 6a of the AC bias signal generator 6 is supplied to the detection coil of the reproducing magnetic head 4 via the capacitor 1. In this case, the AC bias signal generator 6 is configured to generate a signal of, for example, 100 Kll2, and supply to the reproducing head 4 a current of 25 mA or less, such as 50 mA or less, which does not erase the signal recorded on the magnetic tape. Furthermore, the low-pass filter 5 has such characteristics as to remove this AC bias signal, and the output signal of the low-pass filter 5 is supplied to the output terminal 9 via the preamplifier 8. 30 Since the present invention is constructed as described above, when the signal recorded on the magnetic tape is an audio signal with a waveform as shown in curve 2 in FIG. 3, the signal reproduced by the reproducing magnetic head 4 is An AC bias signal 6a is superimposed on this audio signal 2, and this reproduction magnetic 35-magnetic head 4
On the output side, a signal in which the audio signal 2 is superimposed on the AC bias signal 6a as shown in the curve 3a in Fig. 3 is obtained, and the reproduced signal superimposed on this AC bias signal is generated by the ferrite core as shown in Fig. 3. Since the area near the initial magnetic permeability of the B-H characteristic is not used, but a portion with good linearity is used, the signal is not distorted due to distortion of the initial magnetic permeability, and high-quality high-eye sound can be obtained.

Also, since the noise contained in the signal is affected at a very high frequency, there is also the advantage that the noise is generally reduced. In fact, according to this example, when listening to music, the resolution in the high range is improved, the scale becomes clearer, there is less sluggishness in the low range, and distortion in high frequencies is reduced, resulting in an extremely improved sound quality. In the above-described embodiment, the present invention is applied to a magnetic head, but it goes without saying that the present invention can also be applied to a linear AC signal transmission device using a ferrite core such as a transformer and an inductance.

Furthermore, in the above embodiment, it has been described that an AC bias signal is supplied to the reproducing magnetic head 4, but a DC bias signal may be supplied instead, or other means may be used to control the magnetic flux to the reproducing magnetic head 4. It is easy to understand that the same effects as those of the above-mentioned embodiments can be obtained even if .

[Brief explanation of drawings]

1 and 3 are diagrams for explaining the present invention, respectively, and FIG. 2 is a configuration diagram showing an embodiment of the linear AC signal transmission device of the present invention. 4 is a magnetic head using a ferrite core, and 6 is an AC bias generator.

Claims (1)

[Claims] 1 In a linear AC signal transmission device in which a coil is wound around a ferrite core, an AC bias magnetic flux having a higher frequency than the AC signal to be transmitted is supplied to the ferrite core, and a signal component due to the AC bias magnetic flux is removed from the output side. A linear alternating current signal transmission device characterized by being provided with a filter.