JPH04263153A - Index signal recording circuit of tape recorder - Google Patents

Abstract

PURPOSE:To provide an index signal recording circuit which is used for detection of a position where required information is recorded. CONSTITUTION:If an index signal recording operation switch 16 is pushed to close, an index signal is outputted from an index signal recording control circuit 17. The frequency of the outputted index signal is selected by the selecting operation of a selection switch 19.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tape recorder, and more particularly to a recording circuit for a signal called an index for locating information recorded on a magnetic tape.

0002

2. Description of the Related Art Cassette type tape recorders that use a cassette tape in which a magnetic tape is stored in a container called a cassette have become widespread. Such a cassette-type tape recorder can be miniaturized and has excellent operability, so it is generally used as a means for recording the contents of meetings and the like in place of memos. Among the tape recorders used in place of notes, there is one called a dictating machine, which is used in combination with a tape recorder used in conjunction with a typewriter called a transcriber machine. Such a tape recorder is
Generally, it has a function to find the position where the necessary information is recorded by detecting the index signal recorded on the magnetic tape while running at high speed.

0003

The above-mentioned index signal is generally recorded at a low frequency of about 15 Hz, so that it cannot be heard during playback at normal driving speeds. When the vehicle is driven at high speed in order to find the location where the necessary information is recorded, the 15Hz index signal will be reproduced as a 300Hz signal, which is 20 times as large as the signal, and by detecting this signal, the desired information can be retrieved. You can quickly find it and play it for listening. Generally, a cassette tape that has been recorded while being installed in a dictating machine is installed in a transcriber machine and played back.
Those who do not own a transcriber machine will use a dictating machine to perform the reproduction operation. Such a dictating machine is a portable tape recorder and is small, so its speed at high speeds is slower than that of a transcriber machine. Therefore, when a signal with a frequency of about 15Hz is used as an index signal, the frequency of the index signal reproduced during high-speed driving becomes low, making it difficult to accurately detect the index signal. be. The present invention aims to provide an index signal recording circuit that is improved in this respect.

0004

[Means for Solving the Problems] The index signal recording circuit of the present invention includes an index signal recording operation switch that is pressed and closed during the index signal recording operation, and an index signal recording operation switch that is pressed and closed when the index signal recording operation is performed. an index signal recording control circuit that selects and outputs first and second index signals of different frequencies when the index signal recording control circuit enters an operating state; and a selection switch that selects the frequency of the index signal output from the index signal recording control circuit. It is composed of

[0005]

[Operation] The present invention is capable of selectively switching the frequency of an index signal recorded on a magnetic tape in order to search the position of the signal recorded on the magnetic tape while running at high speed. It is.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The circuit shown in FIG. 1 is an embodiment of the index signal recording circuit of the present invention, and FIG. 2 is a perspective view of the main parts of a tape recorder incorporating the present invention. In the figure, numerals 1, 2, 3 and 4 are recording and playback switches for switching between recording operation and playback operation, and common terminals 1c and 2c, respectively.
, 3c, 4c, reproduction side terminals 1p, 2p, 3p, 4p, and recording side terminals 1r, 2r, 3r, 4r. Reference numeral 5 designates a recording/playback magnetic head that operates as a recording head during recording operation and as a playback head during playback operation, and its signal terminal is connected to recording/playback selector switch 1.
is connected to the common terminal 1c. 6 is a microphone that converts an acoustic signal into an electrical signal; 7 is a microphone amplifier circuit that receives a recording signal obtained from the microphone 6 and amplifies the signal; its output terminal is connected to the recording/playback switch 2; It is connected to the side terminal 2r. Reference numeral 8 denotes a preamplifier circuit that amplifies the playback signal or recording signal inputted through the recording/playback selector switch 2, and 9 a variable resistor to which the signal amplified by the preamplifier circuit 8 is applied and adjusts its level. vessel, 1
Reference numeral 0 designates a main amplification circuit to which the signal level-adjusted by the variable resistor 9 is input and which amplifies the signal, and its output terminal is connected to the playback side terminal 4p of the recording/playback changeover switch 4. Reference numeral 11 denotes a speaker to which the reproduction signal amplified by the main amplifier circuit 10 is applied through the recording/reproduction changeover switch 4 during reproduction operation, and has the function of emitting sound of the reproduction signal. Reference numeral 12 denotes a recording amplifier circuit which receives the recording signal amplified by the preamplifier circuit 8 during recording operation through the recording/playback selector switch 3 and amplifies the signal.
The recording/playback selector switch 1 via the signal correction circuit 13
is connected to the recording side terminal 1r. 14 is control terminal 1
a switch circuit that closes the open/close switch 15 when an H (high) level signal is applied to 4a;
16 is an index signal recording operation switch that is pressed and closed during the index signal recording operation; 17 is an index signal recording control circuit that is activated when the index signal recording operation switch 16 is pressed and closed;
When the index signal recording operation switch 16 is closed, an H level signal is output for a predetermined period of time, and a switching signal output terminal 18 connected to the control terminal 14a of the switch circuit 14 is provided. 19 is a selection switch that selects the frequency of the index signal output from the index signal recording control circuit 17; 20 is provided in the index signal recording control circuit 17 and is used to record and playback via a resistor 21 and the open/close switch 15; This is a first index signal output terminal connected to the recording side terminal 1r of the changeover switch 1, and is configured such that a first index signal of, for example, 15Hz is output when the selection switch 19 is in the illustrated state. . 22 is a second index signal output terminal provided in the index signal recording control circuit 17 and connected to the recording side terminal 1r of the recording/playback changeover switch 1 via the resistor 23 and the opening/closing switch 15; When the switch 19 is in a state opposite to the illustrated state, a second index signal of, for example, 50 Hz is output.

FIG. 2 is a perspective view of the main parts of the tape recorder in which the circuit of FIG. , 26 is a battery lid provided to cover the opening of the battery storage section 25, and 27 is a power terminal that comes into contact with the + terminal of the battery when the battery is stored in the battery storage section 25. It is. In such a configuration, a through hole 29 is formed in the side wall 28 constituting the battery storage section 25.
The switch 19s of the selection switch 19 is configured to protrude through the selection switch 19. Therefore, the switching operation of the selection switch 19 is performed with the battery cover 26 opened and the battery removed from the battery storage section 25.

The index signal recording circuit of the present invention is constructed as described above, and its operation will be explained next. When the user performs a playback operation, the magnetic tape drive mechanism etc. become in a state to perform a playback operation, and power is supplied to each circuit, so that the tape recorder enters a state to perform a playback operation. The reproduced signal reproduced by the recording/reproducing magnetic head 5 is input to the preamplifier circuit 8 through the recording/reproducing changeover switches 1 and 2. The reproduced signal input to the preamplifier circuit 8 is amplified and then applied to a variable resistor 9 to adjust its level. The playback signal whose level has been adjusted by the variable resistor 9 is input to the main amplifier circuit 10, amplified, and then applied to the speaker 11 through the recording/playback switch 4. Therefore, since the reproduced signal reproduced from the magnetic tape is emitted by the speaker 11, the user can listen to the reproduced signal.

The reproduction operation is performed as described above, but the recording operation will be explained next. When the user performs a recording operation, the magnetic tape drive mechanism etc. enter the recording operation state, power is supplied to each circuit, and the recording/playback selector switches 1, 2, 3, and 4 are turned on the opposite side from the state shown in the diagram. The recording operation state of the tape recorder is configured by switching to a certain recording side. The recording signal converted into an electric signal by the microphone 6 is input to a microphone amplifier circuit 7, amplified, and then input to a preamplifier circuit 8 through a recording/playback changeover switch 2. The recording signal input to the preamplifier circuit 8 is amplified and then input to the recording amplifier circuit 12 through the recording/playback switch 3. The recording signal inputted to the recording amplifier circuit 12 is amplified and then sent to the recording/playback magnetic head 5 together with a bias signal supplied from a bias oscillation circuit (not shown) through the signal correction circuit 13 and the recording/playback changeover switch 1. is applied to
Recording is performed on a magnetic tape by the recording/reproducing magnetic head 5. In this way, the recording operation of the recording signal obtained from the microphone 6 is performed, but since the signal path to the speaker 11 is cut off by the recording/playback selector switch 4 during the recording operation state, the signal is not transmitted from the speaker 11. No signal is emitted. Therefore, no acoustic coupling occurs between the microphone 6 and the speaker 11, and the phenomenon called howling does not occur.

As described above, the recording signal obtained by the microphone 6 is recorded.Next, the index signal recording operation will be explained. The index signal recording operation is performed by pressing and closing the index signal recording operation switch 16 in the above-described recording operation state. When the index signal recording operation switch 16 is pressed and closed when the recording operation is in progress and the selection switch 19 is in the state shown in the figure, the index signal recording control circuit 17 is activated and the switching signal output terminal 18 is turned on. A signal at H level is output for a predetermined period of time, and at the same time, a first index signal, which is a signal at 15 Hz, is output to the first index signal output terminal 20. When an H level signal is output to the switching signal output terminal 18, the switch circuit 14 becomes operational,
The open/close switch 15 is kept closed for a predetermined period of time. As a result, the first index signal output to the first index signal output terminal 20 is transmitted to the resistor 21 and the open/close switch 15.
The first index signal is applied to the recording/reproducing magnetic head 5 through the recording/reproducing switch 1, so that the first index signal is recorded on the magnetic tape. In this way the first
The recording operation of the index signal is started, but after a predetermined period of time, the output signal of the switching signal output terminal 18 provided in the index signal recording control circuit 17 is inverted to L (low) level, and the operation of the switch circuit 14 is reversed. Since the open/close switch 15 is opened, the recording operation of the first index signal by the recording/reproducing magnetic head 5 is completed. When the index signal recording operation switch 16 is pressed and closed, the above-described index signal recording operation is performed, so that the first index signal, which is a 15 Hz signal, is recorded on the magnetic tape for a predetermined period of time.

As described above, the recording operation of the first index signal is performed. Next, the recording operation of the second index signal will be explained. The recording operation of the second index signal is performed by pressing and closing the index signal recording operation switch 16 while the selection switch 19 is switched to the opposite side from the illustrated state. The switching operation of the selection switch 19 is performed by opening the battery cover 26 provided in the cabinet 24 and removing the battery stored in the battery storage section 25, as shown in FIG. 2, and then switching the switch 19s. It is done by doing. In this way, the selection switch 19 is switched to the opposite side from the state shown in the figure. When the index signal recording operation switch 16 is pressed and closed in this switched state, a predetermined signal is output to the switching signal output terminal 18. At the same time, the second index signal, which is a 50Hz signal, is output to the second index signal output terminal 22. The second index signal outputted to the second index signal output terminal 22 is applied to the recording/playback magnetic head 5 through the resistor 23, the open/close switch 15, and the recording/playback changeover switch 1, and is recorded on the magnetic tape. When the index signal recording operation switch 16 is pressed and closed, the recording operation described above is carried out, so that the second index signal, which is a 50 Hz signal, is recorded on the magnetic tape.

In this embodiment, two output terminals, a first index signal output terminal 20 and a second index signal output terminal 22, are provided, and the configuration is such that two index signals of different frequencies are output from one output terminal. You can also. Further, although the case has been described in which the switch 19s of the selection switch 19 provided to switch the frequency of the index signal is provided in the battery compartment 25, it may also be provided in a compartment where a cassette tape is loaded. be.

[0013]

[Effects of the Invention] The index signal recording circuit of the present invention has the following features:
Users who can perform playback operations with a tape recorder called a transcriber machine, which can switch the frequency of the index signal recorded on magnetic tape and can search at high speeds, can:
Users who must record low-frequency index signals and perform playback operations with a tape recorder called a dictating machine, which cannot increase the running speed of the magnetic tape, record high-frequency index signals. This has the effect that the tape recorder can accurately search for the location where desired information is recorded.

[Brief explanation of the drawing]

FIG. 1 is an embodiment of an index signal recording circuit of the present invention.

FIG. 2 is a perspective view of essential parts of a tape recorder incorporating the index signal recording circuit of the present invention.

[Explanation of symbols]

1, 2, 3, 4 Recording/playback selector switch 5 Recording/playback magnetic head 6 Microphone 8 Preamplifier circuit 12 Recording amplifier circuit 16 Index signal recording operation switch 17
Index signal recording control circuit 19 Selection switch 25 Battery compartment

Claims (1)

[Claims] 1. A tape recorder configured to record a recording signal obtained from a microphone onto a magnetic tape, comprising: an index signal recording operation switch that is pressed and closed during an index signal recording operation; an index signal recording control circuit that becomes operational when an operation switch is pressed and closed and selects and outputs first and second index signals of different frequencies; and an index signal output from the index signal recording control circuit. A tape recorder index signal recording circuit consisting of a selection switch that selects the frequency of the tape recorder.