JPH01158601A - Reproducing circuit for magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To construct a reproducing circuit broadband and strong against extraneous noise by providing a reproducing amplifier and a magnetic head connected directly with each other and eliminating influence by floating capacity. CONSTITUTION:A signal reproduced by a magnetic head 5 from a recording medium is inputted to a reproducing amplifier 6 on a rotary cylinder. The most suitable characteristic of the magnetic head 5 exists in inductance the power source characteristic and the frequency characteristic of the amplifier 6 correspond to the request of a reproducing symbol. The amplifier 6 executes an amplifying action with a battery 7 set on the rotary cylinder as power source and outputs an amplified signal to rotary transformer 8. The input of the transformer 8 is inputted to a signal processing part 9, the processing part 9 executes various processings and prepares the data of a picture and a voice. The battery is charged while the signal is not reproduced. Thus, when the head 5 is connected directly with the amplifier 6, the floating capacity held by the rotary transformer 8 is eliminated and the reproducing circuit broadband and strong against the extraneous noise can be constructed with simple circuits.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a reproducing circuit for a rotary head type magnetic recording/reproducing device.

2. Description of the Related Art A block diagram of a reproducing circuit of a conventional rotary head type magnetic recording/reproducing apparatus is shown in FIG. In FIG. 3, 1 is a magnetic head, 2 is a rotating transformer, 3 is a regenerative amplifier, and 4 is a signal processing section. A minute signal reproduced from a recording medium by a magnetic head 1 is input to a reproduction amplifier 3 through a rotary transformer 2. The regenerative amplifier 3 converts this minute signal into a high-gain,
The signal is amplified with low noise and output to the signal processing unit 4.
Then, data such as images and audio are reproduced from this input signal.

Problems to be Solved by the Invention In the reproducing circuit of such a conventional magnetic recording/reproducing device, since the signal transmitted by the rotary transformer is at a minute level,
It is easily affected by external induced noise, crosstalk from other channels, etc., and has problems in terms of operational stability. Additionally, since there is stray capacitance of the rotating transformer and capacitance of the shielded wire for connection, there is a problem in that these capacitances and the inductance of the magnetic head cause resonance, which limits the transmission band. Ta.

The present invention has been made in view of the above points, and an object of the present invention is to provide a reproducing circuit for a magnetic recording/reproducing device that has a simple configuration, is resistant to noise, and has a wide band.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a rotary head type magnetic recording/reproducing device that transmits signals using a rotary transformer, in which a rotating cylinder on which a magnetic head is attached. It has a battery and a regenerative amplifier on its side, connects the output of the magnetic head to the input of the regenerative amplifier, supplies the output of the regenerative amplifier to a rotating transformer, and extracts a reproduced signal from the output of the rotating transformer. It is something.

Function: With the above-described configuration, the present invention allows direct connection of the magnetic head and the regenerative amplifier, thereby enabling broadband transmission without being affected by stray capacitance or the like. Furthermore, since the level of the signal transmitted by the rotary transformer increases, it becomes less susceptible to external noise and stable operation becomes possible.

Embodiment FIG. 1 is a block diagram of a reproducing circuit of a magnetic recording/reproducing apparatus in a first embodiment of the present invention.

In FIG. 1, 5 is a magnetic head, 6 is a rotating transformer,
7 is a regenerative amplifier, 8 is a battery, and 9 is a signal processing section. A signal reproduced from the recording medium by the magnetic head 5 is input to a reproducing amplifier 6 on a rotating cylinder. Regenerative amplifier 6
performs an amplification operation using the battery 7 installed on the rotating cylinder as a power source, and outputs the amplified signal to the rotating transformer 8. The output of the rotary transformer 8 is input to a signal processing section 9, where it undergoes various processing and reproduces data such as images and audio. Here, the magnetic head 5 has optimum characteristics such as inductance that are different from the magnetic head 1 shown in FIG. 3, and the regenerative amplifier 6 also has different power supply characteristics and frequency characteristics than the regenerative amplifier 3. are required, so use one with characteristics that suit each. As for the signal processing section 9, almost the same one as the signal processing section 4 of FIG. 3 can be used, with some differences in the interface of the input section.

FIG. 2 is a block diagram of a reproducing circuit of a magnetic recording/reproducing apparatus according to a second embodiment of the present invention.

In FIG. 2, 5 to 9 are the same as those in FIG. 1, so their explanation will be omitted here. In FIG. 2, 10 is a charging control circuit, which can most simply be constructed from a diode. 1) is a changeover switch circuit, and 12 is a charging power supply circuit. The operation will be explained below. During normal playback, the changeover switch circuit 1) is connected to the signal processing section 9 side, and the charging control circuit IO and the charging power supply circuit 12 are kept in the OFF state. At this time, the same operation as in FIG. 1 is performed. Note that the charging control circuit 10
Even when configured with a diode, the maximum output amplitude of the regenerative amplifier 6 is determined by the forward rising voltage of the diode (approximately 0.6
V) The OFF state is realized by designing the following.

When the reproduction signal is not output, for example, when the magnetic head 5 is not in contact with the recording medium, the changeover switch circuit 1) is switched to the side of the charging power supply circuit 12, and power is supplied from the charging power supply circuit 12 to the rotating cylinder. A signal to do this, for example, a high frequency current of several hundred K I (z, several tens of mA) is output to the rotary transformer 8.The rotary transformer 8
The charge control circuit 10 converts the transmitted current into direct current to charge the battery 7. Note that the battery 7 can also be replaced with a large capacity capacitor.

Effects of the Invention As described above, according to the present invention, it is possible to construct a reproduction circuit of a magnetic recording and reproduction device that has a wide band and is resistant to external noise with a simple circuit, and is extremely useful.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a reproducing circuit of a magnetic recording/reproducing apparatus according to a first embodiment of the present invention, and FIG. 2 is a block diagram of a reproducing circuit of a magnetic recording/reproducing apparatus according to a second embodiment of the present invention. FIG. 3 is a block diagram of a reproducing circuit of a conventional magnetic recording/reproducing device. 1.5... Magnetic head, 2.8 Old... Rotating transformer, 3.6... Regenerative amplifier, 4.9...
...Signal processing unit, 7...Battery or capacitor, 1o...Charging control circuit, 12...
Charging power supply circuit. Name of agent: Patent attorney Toshio Nakao (1 person) Figure 1 Figure 2 Figure 3

Claims (3)

[Claims] (1) A rotary head type magnetic recording/reproducing device that transmits signals using a rotary transformer, which has a battery and a regenerative amplifier on the side of a rotating cylinder to which a magnetic head is attached, and outputs from the magnetic head. 1. A reproducing circuit for a magnetic recording/reproducing apparatus, characterized in that the reproducing circuit is connected to an input of a reproducing amplifier, supplies the output of the reproducing amplifier to a rotary transformer, and extracts a reproduced signal from the output of the rotary transformer. (2) Reproduction of a magnetic recording and reproducing apparatus according to claim (1), characterized in that a current for charging a battery is supplied through a rotating transformer during a period when a signal is not being reproduced from a recording medium. circuit. (3) A reproducing circuit for a magnetic recording/reproducing device according to claim (2), characterized in that a capacitor is used instead of a battery.