JPS6045904A - Oscillator of tape recorder - Google Patents

Abstract

PURPOSE:To reduce the variance of forward and backward recording by arranging the 1st oscillation part supplying bias current to sound recording heads and the 2nd oscillation part supplying erase current to erase heads independently. CONSTITUTION:The bias current output of the 1st oscillation part 11 is supplied to the sound recording head 2 together with the sound recording current output of a sound recording amplifier 7. At the forward sound recording, the erase current output of the 2nd oscillation part 12 supplied to the erase head 3 through a terminal (a) of a switch 5 to execute the forward sound recording. At the backward sound recording, the switch element 5 is turned to the (b) side and the erase current output of the 2nd oscillation part 12 is supplied to the 2nd erase head 4 to execute the backward sound recording. Since the 2nd oscillation part 12 for supplying erase current and the 1st oscillation part 11 for supplying bias current are independently arranged, current change due to the variance of the impedance difference between the 1st and 2nd erase heads 3, 4 is not generated after once adjustment and it is unnecessary to adjust bias current at the switching of recording, so that the adjusting work can be simplified.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an oscillation device for a tape recorder capable of reciprocating recording.

2. Description of the Related Art Structures of Conventional Examples and Their Problems In recent years, various types of tape recorders capable of reciprocating recording (hereinafter referred to as reverse recording tape recorders) have been proposed.

An example of an oscillating section of a conventional recording reverse tape recorder will be described below.

FIG. 1 is a diagram showing an embodiment of the oscillation section of a conventional recording reverse tape recorder, in which 1 is a tape running system that can travel back and forth, 2 is a recording head installed in the tape running system 1, and the tape running system is The tape is configured so that it rotates in accordance with the traveling direction of No. 1, and the track to be recorded on the tape is switched.

3 is a first erasing head, and 4 is a second erasing head, each of which is installed in the tape running system 1, and the erasing head on the upstream side of the recording head 2 with respect to the running direction during normal rotation and reverse rotation, respectively. It is now activated. Reference numeral 6 denotes a first switch element that is switched in conjunction with the running direction of the tape running system 1, and the output of the oscillating unit 6, which will be described later, is sent to the first erasing head 3 when the tape is running in the normal direction, or vice versa, depending on the running direction of the tape. During travel, each of them is switched and supplied to the second erasing head.

Reference numeral 6 denotes an oscillator which supplies an erase current to the first switch element 6 and also supplies a bias current to a second switch element 8, which will be described later. Reference numeral 7 denotes a recording amplification section that amplifies the recording signal, and its output is supplied to the recording head 2 as a recording current. 8 is a second switch element that operates in conjunction with the running direction of the tape running system 1;

A bias current output from the oscillator 6 is supplied to the recording head 2 through a first semi-fixed resistor 9 or a second semi-fixed resistor 10, which will be described later, depending on the tape running direction. 9 is a first semi-fixed resistor for bias current adjustment during forward running; 10
is the second semi-fixed resistor of the flow adjustment phase during reverse running.

The operation of the conventional reverse tape recorder oscillation device configured as described above will be described below.

First, during normal rotation, the first switch element 6 and the second switch element 8 are connected to the a side, and the output of the oscillator 6 is transmitted from the terminal a of the first switch element 6 to the first erasing head 3. On the other hand, the bias current output of the oscillator 6 is supplied to the second
The bias current is adjusted by the first semi-fixed resistor 9 and supplied to the recording head 2 through the terminal a of the switch element 8, and the recording current output from the recording amplifier 7 is also supplied to the recording head 2. Recording is performed during normal rotation. During reverse running, the first switch element 6 and the second switch element 8 are connected to the b side, and the erase current from the oscillator 6 passes through the terminal of the first switch element 5 to the second erase head 4. The bias current output from the first oscillator 6 passes through the terminal of the second switch element 8, the bias current is adjusted by the second semi-fixed resistor 10, and is supplied to the recording head 2. will be recorded.

However, in the conventional configuration described above, due to variations in impedance between the first erasing head 3 during forward rotation and the second erasing head 4 during reverse rotation, the load on the oscillation unit 6 fluctuates, causing its output to fluctuate. Since the bias current changes during forward and reverse recording, the bias current must be adjusted each time the vehicle is running, which increases the amount of adjustment work.
There was also a problem in that due to variations in adjustment, there were differences in recording characteristics between normal rotation and reverse rotation. In addition, although electronic switching is often used as switching elements these days, the bias current is switched between forward and reverse rotation, so there is the problem that switching the bias current for general high voltages becomes expensive. Was.

purpose of invention The present invention solves the above-mentioned conventional problems.

An object of the present invention is to provide an oscillation device for a recording reverse tape recorder that simplifies the adjustment of bias current and reduces variations between normal rotation and inversion.

Structure of the Invention The present invention includes a tape running system capable of reciprocating, a recording head, a first erasing head installed upstream of the recording head with respect to the normal running direction of the tape running system, and a reverse running direction. a second erasing head installed upstream of the recording head; and a first oscillator supplying a bias current to the recording head.

An oscillation device for a reverse tape recorder, comprising a second oscillation section independent of the first oscillation section that supplies erase current to the first erase head and the second erase head, the oscillation device for supplying erase current. By making the oscillation section and the oscillation section for bias current supply independent, bias current adjustment can be simplified and variations during forward and reverse recording can be reduced.

In addition, the oscillation frequency is shifted so that the difference between the oscillation frequency of the oscillation part of the oscillation part for supplying the erase current and the oscillation frequency of the oscillation part of the oscillation part for supplying the bias current of the oscillation device of the reverse tape recorder configured as above is outside the audible frequency. By setting
The beats of the outputs of the two oscillators are not recorded, and recording can be performed without unnecessary signals.

DESCRIPTION OF THE EMBODIMENTS FIG. 2 shows a main part of an oscillation device for a rick-staple recorder in an embodiment of the present invention.

1 is a tape running system, 2 is a recording head, 3 is a first erasing head, 4 is a second erasing head, 6 is a switch element, and 7 is a recording amplification section, which have the same configuration as the conventional example. be. Reference numeral 11 denotes a first oscillation section, which supplies a bias current to the recording head 2.

Reference numeral 12 denotes a second oscillation section, which is connected to the C terminal of the switch element 5.

The operation of the oscillation device for the glue/staple recorder of the embodiment shown in FIG. 2 constructed as described above will be described below. First, the bias current output of the first oscillation section 11 is supplied to the recording head 2 together with the recording current output of the recording amplifier section 7. During normal rotation recording, the switch element 6, which switches in conjunction with the tape running system 1, is on the a side, so the erase current output of the second oscillating section 12 passes through the a terminal of the switch element 5 to the first eraser. The signal is supplied to the head 3, and normal rotation recording is performed. Similarly, when recording in reverse, switch element 6 is set to b.
The erasing current output of the second oscillating section 12 is supplied to the second erasing head 4 to perform inversion recording.

As described above, according to this embodiment, the second oscillation section 12 for supplying erase current and the first oscillation section 1 for supplying bias current
1 is provided independently, once it is adjusted, there is no change in bias current due to variations in the impedance difference between the first erasing head 3 and the second erasing head 4 during forward recording and reverse recording.

Since it is no longer necessary to adjust the bias current separately for forward recording and reverse recording, the adjustment work can be simplified. Furthermore, since separate adjustments are not made for forward recording and reverse recording, differences in recording characteristics between forward recording and reverse recording due to variations in adjustment can be eliminated. In addition, as there is no separate adjustment between normal rotation and inversion as described above, there is no need for a high voltage bias signal switching element.
In particular, when an electronic switch is used as a switch element, it can be constructed at low cost because a high voltage switching circuit, which is complicated and expensive, is not used.

Next, other embodiments of the present invention will be described.

FIG. 3 shows the main parts of an oscillation device for a reverse tape recorder according to another embodiment of the present invention. In FIG. 3, 1 is a tape running system, 2 is a recording head, 3 is a first erasing head, 4 is a second erasing head, 7 is a recording amplification section,
Reference numeral 11 denotes a first oscillation section, which is the same as the embodiment shown in FIG.

Reference numeral 12 denotes a second oscillator that supplies an erase current to the first erase head 3. A third oscillation section 13 supplies an erase current to the second erase head 4. 15 is a power supply terminal; 14 is a switch element that switches in conjunction with the running direction of the tape running system 1; the voltage from the power supply terminal 16 is applied to the second oscillating unit 12 or the third oscillating unit depending on the running direction of the tape running system 1; Supply to section 13.

It is configured to switch between oscillation and stop.

The operation of the oscillation device for a reverse tape recorder constructed as described above will be explained below. First, the bias output current of the first oscillation section 11 is supplied to the recording head 2 together with the recording current output of the recording amplifier section 7. During forward running, there are eight switching elements 14 that switch in conjunction with the running direction, so the voltage at the power supply terminal 16 passes through the a terminal of the switching element 14 and is applied to the second oscillating section 12.
The second oscillator 12 oscillates and erase current is applied to the first erase head 3. Further, the third oscillation section 13 is connected to the switch element 1
4 is off, there is no oscillation and the erase head 4 does not operate.
Normal rotation recording is performed. On the other hand, when traveling in reverse, the switch element 14 is on the b side.

Similarly, the erase current output of the third oscillator 13 is supplied to the second erase head 4, and since the first erase head 3 does not operate, one inversion recording is performed.

As described above, according to this embodiment, the second oscillator 12 supplies the erase current to the first erase head 3 and the second erase head 4 supplies the erase current. The third oscillation section 13 is provided independently of the first oscillation section 11 that supplies a bias current to the recording head 2, and the control voltage is switched to control the oscillation/stop of the second oscillation section 12 and the third oscillation section 13. By controlling by switching with the element 14, the adjustment work can be simplified as in the second embodiment, and the difference in recording characteristics due to variations in adjustment between forward recording and reverse recording can be eliminated. In addition, since the signal switched by the switch element 14 that switches in conjunction with the tape running direction is a DC voltage, the switch element can be easily constructed, especially when electronic switching is used, compared to the case where the bias current or erase current itself is switched. Moreover, since the signal is not a high frequency signal, the position of the switch element can be freely selected during assembly.

In addition, in the embodiments shown in FIGS. 2 and 3, the difference between the oscillation frequencies of the first oscillation section for supplying bias current and the second oscillation section and third oscillation section for supplying erase current is calculated outside the audible frequency range. Set it so that Specifically, for example, the frequency is set to be 50 kEk or higher, which is sufficiently far from the audible frequency so that the bias signal or the cancellation signal is not recorded. Therefore, for example, if the erase current frequency is 50 kHz, the bias current frequency is configured to be about 100 kHz.

With the above configuration, even if a beat occurs between the erase current and the bias current, it will be outside the audible frequency, so
Since it is neither recorded nor audible, it is possible to make good recordings without beat sounds.

Effects of the Invention The present invention provides a second oscillator that supplies an erase current to an erase head independently of a first oscillator that supplies a bias current to a recording head.
By providing an oscillation section, it is no longer necessary to adjust the bias current for forward recording and reverse recording, simplifying the adjustment work.

Furthermore, it is possible to eliminate the difference in recording characteristics due to adjustment variations between forward recording and reverse recording. Also, by making the difference between the frequency of the bias current and the frequency of the erase current outside the audible frequency range.

This allows recording without heat.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of a main part of an oscillation device of a conventional reverse tape recorder, FIG. 2 is a circuit diagram of a main part of an oscillation device of a reverse tape recorder according to an embodiment of the present invention, and FIG. 3 is a circuit diagram of a main part of an oscillation device of a reverse tape recorder according to an embodiment of the present invention. FIG. 2 is a circuit diagram of a main part of an oscillation device of a reverse tape recorder in an example. 1...Tape running system capable of reciprocating, 2...
... Recording head, 3... First erasing head,
4...Second erasing head, 6, 8, 14...
...Switch element. 6...Oscillation section, 7...Recording amplification section, 9
．． 10... Semi-fixed resistor, 11... First oscillation section, 12... Second oscillation section, 13...
...Third oscillation section, 16... Power supply terminal.

Claims (4)

[Claims] (1) A tape running system that can travel back and forth, a recording head,
a first erasing head disposed upstream in the tape running direction with respect to the recording head during normal rotation; and a second erasing head disposed upstream in the tape running direction with respect to the recording head during reverse rotation. , a first oscillating section that supplies a bias current to the recording head, and a second oscillating section that is independent of the first oscillating section that supplies erasing current to the first erasing head and the second erasing head. An oscillation device for a tape recorder, characterized by comprising: (2) A switch element that supplies the output of the second oscillator to the first erasing head or the second erasing head in accordance with the running direction of the tape running system. An oscillation device for a tape recorder according to item 1. (3) a third oscillation unit independent of the first oscillation unit and the second oscillation unit for supplying the output of the second oscillation unit to the first erase head and supplying the erase current to the second erase head; Claim 1: An oscillating section is provided, and a switch element is provided for selecting oscillation or stopping of the second oscillating section and the third oscillating section in conjunction with the running direction of the tape running system. The oscillation device for the tape recorder described in Section 1. (4) Claim 1, characterized in that the oscillation frequency of the first oscillation section and the oscillation frequencies of the second oscillation section and the third oscillation section are shifted so that the difference is outside the audible frequency. An oscillation device for a tape recorder according to item 1 or 2 or 3.