JPH02177005A - Cassette tape recorder - Google Patents

Abstract

PURPOSE:To accomplish a monitor having a small sound or a sound close to a real one by changing the recovery time of an AGC circuit, the frequency characteristic of a recording amplifier and the gain of a microphone input circuit by interlocking with the switching of a pause circuit. CONSTITUTION:When a pause circuit changeover switch 18 is turned on, the recovery time changeover switch 19 of the AGC circuit, the output characteristic changeover switch 23 of the microphone input circuit and the frequency characteristic changeover switch 21 of the recording amplifier are switched from 1 2 by interlocking with turning on the switch 18. As a result, a resistor 20 for changeover is connected to the recording amplifier 4 in series, so that the recovery time is shortened and the amplifier 4 can follow the sudden change of the intensity of an input signal. Since the microphone input circuit is released from a state where a capacitor 16 and a resistor 17 are connected to an earth, the output level of the microphone input circuit is increased and the sound in the distance is made to be listened. Moreover, the clear monitoring sound close to an original sound is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a cassette tape recorder having a recording pause function.

2. Description of the Related Art Conventionally, many small tape recorders, in particular, are equipped with a pause function in which the rotation of a motor is driven and stopped by a switch during recording and playback.

This is because, as the mechanism becomes smaller, it is difficult to realize a pause function using the mechanism, so the mechanism is left as it is and the rotation of the motor is controlled by the switching operation of a switch to drive and stop tape running.

Problems to be Solved by the Invention However, in conventional tape recorders with pause circuits, the operating sounds of internal motors and mechanisms are recorded at the same time as the sound being recorded by the built-in microphone, resulting in recordings with poor clarity. To prevent this as much as possible 1. By lowering the output of the built-in microphone input circuit, the frequency bands of the built-in microphone input circuit and recording amplifier are narrowed. For this reason, in actual use by connecting earphones or the like to the external monitor output terminal and monitoring the recording, it is of course possible to record on tape, but it may also be used as a monitor (hearing aid) to amplify the signal. Therefore, in such uses, conventional devices have had problems such as being unable to hear small sounds or hearing sounds different from actual sounds. Also, AGC
Since the recovery time of the circuit remains set for a long time, it has disadvantages such as the inability to hear small sounds immediately after loud sounds.

The purpose of the present invention is to eliminate the conventional drawbacks and to eliminate the pause circuit.
To provide a cassette tape recorder capable of discriminating small sounds and realizing monitoring with high clarity close to actual sounds by making use of the fact that the operation of a motor and mechanism stops at 8 o'clock and the influence of operating noise disappears. That's true.

Means for Solving the Problems The cassette tape recorder of the present invention includes a pause circuit that drives and stops tape running by switching a switch during recording, an AGC circuit that automatically controls the recording level during recording, and a recording amplifier. It is equipped with an equalizer circuit that determines the frequency characteristics, an input circuit that determines the output level and frequency characteristics from a microphone placed inside the device, and an external monitor output terminal that connects earphones, etc., and a switch switching operation of the pause circuit. In conjunction with, the AGC
The recovery time of the circuit, the frequency characteristics of the recording amplifier, and the gain and frequency characteristics of the microphone input circuit are changed.

Effects of the present invention With the above-described configuration, when the pause circuit is turned on while recording is being monitored using earphones, etc., it is possible to monitor a small sound immediately after a large sound, to distinguish a small sound, and to make it close to the actual sound. It is possible to realize clear sound monitoring.

Embodiment An embodiment of the present invention will be explained based on the drawings. The figure shows the recovery time switching circuit of the AGC circuit, the output level and frequency characteristic switching circuit of the microphone input circuit, and the frequency characteristic switching circuit of the recording amplifier, which are linked to the switch switching operation of the pause circuit of the present invention. In the same figure, 1
is a built-in microphone, 2 is a capacitor for setting the frequency characteristics of the microphone input circuit, 3 is a resistor for setting the output level, 4 is a recording amplifier, 6 is a resistor for setting the AGC circuit recovery time, 6 is a capacitor for setting the recovery time, 7
is a resistor for setting the frequency characteristics of the recording amplifier, 8 is the capacitor for setting the frequency characteristics, 9 is the volume volume, 10 is the power amplifier, 11 is the external monitor output terminal (jack), 12 is the speaker, 13 is the recording/playback head, 14 is a motor, 15 is a governor circuit for controlling the motor, 16 is a capacitor for switching the frequency characteristics of the microphone input circuit, 17 is a resistor for switching the output level, 18 is a pause circuit selection switch, and 19 is a recovery time that works with the selection switch 18. Selector switch, 20 is a recovery time switching resistor,
21 is a recording amplifier frequency characteristic changeover switch that works with the changeover switch 18; 22 is a frequency characteristic changeover capacitor;
Reference numeral 23 denotes a microphone input circuit output characteristic changeover switch which is interlocked with the changeover switch 18.

Next, to explain the operation, the output characteristics of the signal input from the built-in microphone 1 are determined by the microphone input circuit frequency characteristic setting capacitor 2 and output level setting resistor 3.
It is input to recording amplifier 4.

Next, it is amplified by recording amplifier 4, and then the built-in A
The GC circuit automatically controls the level of the recording current flowing to the recording/playback head 13, and the recording amplifier equalizer circuit, which includes a recording amplifier frequency characteristic setting resistor 7 and a capacitor 8, controls the frequency characteristics of the recording current. Furthermore, the level of the signal amplified by the recording amplifier 4 is controlled by the volume control 9, and the signal is input to the power amplifier 1o and amplified.
drives earphones and external speakers. Furthermore, when nothing is connected to the external monitor output terminal (jack) 11, the speaker 12 is driven through the contact of the external monitor output terminal 11. Also, during such recording operation, the pause circuit operates by controlling the motor control governor circuit 15 to control the rotation of the motor 14 and drive and stop tape running in accordance with the switching operation of the pause circuit changeover switch 18. .

In this operation, when the pause circuit changeover switch 18 is changed from 1 to 2 (ON) as shown in the figure, the recovery time changeover switch 19, the microphone input circuit output characteristic changeover switch 23, and the recording amplifier frequency characteristic changeover switch are linked. 21 is also switched from 1 to 2 in the same way, and the recording amplifier 4
Since the switching resistor 2Q is connected in parallel to the recovery time setting resistor 6 of the human GG circuit, the recovery time is shorter than usual, and it can also follow sudden changes in the strength of the input signal. Since the microphone input circuit is released from the state in which the frequency characteristic switching capacitor 16 and the output level switching resistor are connected to ground, the output characteristic of the microphone input circuit is extended in the high frequency range and the output level is increased. do. As a result, distant sounds can be heard better, and the monitor sound is clear and close to the original sound. Furthermore, since the switching capacitor 22 that was connected in parallel to the recording amplifier frequency characteristic setting capacitor 8 is disconnected, and the setting capacitor 8 is left alone, the high range of the frequency characteristic is expanded and a clear monitor sound that is closer to the original sound is created. Become.

Further, in this operation, since the pause circuit changeover switch 18 is in state 2 (OPEN), the motor control governor circuit 15 controls the motor 14 to stop rotating. Therefore, clear monitoring can be performed without the rotation sound of the motor 14 or the operating sound of the mechanism.

Effects of the Invention According to the present invention, by switching the recovery time and frequency characteristics of the AGC circuit of the recording amplifier and the output level and frequency of the microphone input circuit in conjunction with the switch switching operation of the pause circuit, the pause ON state is achieved. Its practical effects are extremely large, as it enables the discrimination of distant sounds, the ability to monitor clear sounds close to the original sound, and the ability to respond to sudden changes in sound strength.

[Brief explanation of the drawing]

The figure is a circuit diagram of a cassette tape recorder in one embodiment of the present invention. 1...Built-in microphone, 2...Capacitor for setting microphone input circuit frequency characteristics, 3...Resistor for setting microphone input circuit output level, 4... Recording amplifier, 5... Resistor for setting AGC circuit recovery time, 6... Capacitor for setting AGO circuit recovery time, 7... Resistor for setting recording amplifier frequency characteristics. , 8... Capacitor for setting recording amplifier frequency characteristics, 11... External monitor output terminal (jack), 16... Capacitor for switching microphone input circuit frequency characteristics, 17... ...Microphone input circuit output level switching resistor, 18...Pause circuit selection switch, 19...Recovery time selection switch, 2o...Recovery time switching resistor, 21... Recording amplifier frequency characteristic selection switch, 22... Recording amplifier frequency characteristic switching capacitor, 23... Microphone input circuit output characteristic selection switch. Name of agent: Patent attorney Shigetaka Awano and one other person, /
Ryo,

Claims (1)

[Claims] A pause circuit that drives and stops tape running by switching a switch during recording, an AGC circuit that automatically controls the recording level during recording, an equalizer circuit that determines the frequency characteristics of the recording amplifier, and a It is equipped with an input circuit that determines the output level and frequency characteristics from the microphone, and an external monitor output terminal that connects earphones, etc., and operates in conjunction with the switch switching operation of the pause circuit to adjust the recovery time of the AGG circuit and the recording amplifier. A cassette tape recorder characterized in that it is configured to change the frequency characteristics of the microphone input circuit as well as the gain and frequency characteristics of the microphone input circuit.