JPS60115002A - Recording and reproducing system of tape recorder - Google Patents

Abstract

PURPOSE:To always keep a fixed ratio of intensity between a reproduction signal obtained from a terminal and a record signal obtained in a record mode, by comparing a reproduced reference signal with a correction signal and performing automatic control for amplification factor of a reproduction amplifier according to the result of said comparison. CONSTITUTION:The output of a sampling/holding element 17 is supplied to an input at one side of a differential amplifier 18. A correction signal (g) is applied to the other input of the amplifier 18 from a correction signal generator 18. Therefore the voltage corresponding to the difference between both inputs appears at the output of the amplifier 18. This voltage is supplied to an amplification degree control input terminal of a reproduction amplifier 15 whose amplification degree can be controlled. The amplification degree of the amplifier 15 increases under the control of the output of the amplifier 18 in case the reference signal (d) held by the element 17 is smaller than the signal (g) produced by the generator 80 and then decreases vice versa. Therefore the automatic control is performed for the amplification degree of the amplifier 15 so that the coinci dence is obtain ed between the reproduced signal (d) and the signal (g). Thus a fixed ratio of intensity is always secured between the recording and the reproducing. Then the coincidence is obtained for the intensity between the recording and reproducing if said ratio is set at 1.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording/reproducing method for a tape recorder, and particularly to a recording/reproducing method for a tape recorder having multiple recording channels.

Conventional tape recorders with multiple recording channels require a recording amplifier to keep the ratio of the signal strength during recording to the signal strength during playback (hereinafter referred to as the recording/playback intensity ratio) constant for each channel.

Highly accurate adjustment of many elements such as the playback amplifier and the alignment of the head and tape is required, and especially when the tape recorder used for recording and the tape recorder used for playback are different, the recording and playback strength of each channel is required. It has the disadvantage that it is very difficult to keep the ratio constant.

For example, in a conventional tape recorder, when trying to record and reproduce a signal that contains certain information in the relative relationship of signal intensities of each channel, it is necessary that the recording and reproduction intensity ratio of each channel be constant. When the X-axis signal and the X-axis signal of the Lissage figure are recorded on a multi-channel tape recorder and played back, if the recording/reproduction intensity ratio of each channel is different, it is impossible to reproduce the same or similar Lissage figure as when it was recorded. It had drawbacks such as being impossible.

The purpose of the present invention is to eliminate the drawbacks of conventional multi-channel tape recorders, and to maintain a constant recording/reproduction intensity ratio by automatically adjusting the amplification degree during reproduction.
It is an object of the present invention to provide a recording and reproducing method for a tape recorder that can reproduce data without losing the relative relationship of signal intensities during recording of each channel.

Another object of the present invention is to record a reference signal (hereinafter referred to as a reference signal) having a constant signal strength on each channel in a time division manner with the signal to be recorded, and to record the reference signal (hereinafter referred to as reference signal) with a constant value of signal strength in a time-division manner with the signal to be recorded, and to By detecting the reference signal included in the division and automatically adjusting the amplification degree of the reproduction amplifier so that the detected reference signal has a constant value, the recording and reproduction intensity ratio is kept constant and the recording of each channel is performed. The reproduction intensity ratio can be made equal,
It is possible to provide a recording and reproducing method for a tape recorder that can reproduce data without losing the relative relationship of signal intensities during recording of each channel.

According to the present invention, a recording side circuit includes means for interposing a signal strength reference signal in a time-division manner with a recorded signal on a magnetic tape, and a reproduction side circuit for detecting the reproduced reference signal; A recording and reproducing method for a tape recorder, comprising means for comparing the strength of the detected reference signal with the strength of a calibration signal, and further comprising means for controlling the amplification degree of a reproducing amplifier as a result of the comparison. is obtained.

Next, embodiments of the present invention will be described with reference to the drawings.

The drawing shows a tape recorder with multiple channels, which is an embodiment of the invention. In the figure, this embodiment has channels 1 to 3, and channels 1 and 2 are assigned a recording signal (aJ and recording signal (b)), and channel 3 is assigned an identification signal for identifying a reference signal. A signal is assigned.

m Separate signal (C) id is a digital signal that has two states, high level and low level, when it is at no level, a reference signal is recorded on the magnetic tape 70, and when it is at low level, a normal recording signal is recorded. A reference signal is interposed in the recording signal in a time-division manner and recorded on the magnetic tape.

In this embodiment, channel 1 and channel 2 have the same components and operations, so only channel 1 will be described below.

The recording side circuit of channel 1 includes a switch 11 which is switched by the identification signal C, amplifies the recording signal (al) and a reference signal d from the reference signal generator 60, and a recording amplifier 12, which amplifies each signal. It is often referred to as a recording head 13 for recording on a magnetic tape.

To explain the operation when recording channel 1, switch 1
1, the recording signal (a) and the reference signal d from the reference signal generator 60 are input. The switch 11 is the identification signal C
When the identification signal is low level, the recording signal (a) is selected, and when the identification signal is high level, the reference signal d is selected.
is selected and supplied to the recording amplifier 12. The selected signal is amplified by the recording amplifier 12, and the recording head 1
3, the information is recorded on the magnetic tape 70 in a time-division manner.

On the other hand, to explain the operation of channel 3 during recording, the identification signal C supplied from the outside is amplified by the recording amplifier 31 and recorded on the magnetic tape 70 through the entire recording head 32.

In this way, the recording signal a of channel 1 and the identification signal C of channel 3 are simultaneously recorded on the magnetic tape 70, and when the identification signal C of channel 3 is recorded at the same time, the reference signal d of channel 1 is recorded. is recorded, and when the identification signal C of channel 3 is recorded at a low level, a recording signal (al) is recorded on channel 1.

Next, to explain the reproduction side circuit, the reproduction side circuit of channel 1 includes a reproduction head 14 for reproducing the signal of the magnetic tape 70, a reproduction amplifier 15 whose amplification degree can be controlled by an amplification degree control input, and a reproduction side circuit of channel 1. A switch 16 for switching between signal transmission and control of the amplification degree of the reproducing amplifier 15, a sample/hold element 17 that receives and holds an input voltage under the control of the control input, and an output of the sample/hold element 17 and a reproducing side. and a differential amplifier 18 that generates a voltage difference from the calibration signal supplied from the calibration signal generator 80 of.

To explain the operation on the reproduction side of channel 1, the signal f reproduced by the reproduction head 14 is amplified by the reproduction amplifier 15 and supplied to the switch 16. The switch 16 is switched by the regenerated identification signal e supplied from the regenerative amplifier 34 of channel 3, and when the identification signal e is at a low level, the output of the regenerative amplifier 15 is supplied to the terminal 19. ,
When it is at a high level, it is supplied to the sample/hold element 17. The reproduced identification signal e is input to the control input terminal of the sample/hold element 170, and when the identification signal e is at a high level, it receives the voltage supplied from the switch 16, and when it is at a low level, it receives the input voltage. hold. When the identification signal e of channel 3 is recorded at a high level on the magnetic tape 70, the reference signal d is recorded on channel l, so the sample/hold element 17 always receives the reproduced reference signal d. It is taken in.

The output of sample/hold element 17 is supplied to one input of differential amplifier 18. The calibration signal 1 from the reproduction side calibration signal generator 80 is input to the other input of the differential amplifier 18 . Therefore, a voltage corresponding to the difference between the two is applied to the output of the differential amplifier 18, and this voltage is supplied to the amplification control input terminal of the reproduction amplifier 15 whose amplification degree can be controlled. The amplification degree of the reproducing amplifier 15 is determined by controlling the output of the differential amplifier 18, so that the reference signal d held by the sample/hold element 17 is adjusted with respect to the calibration signal 2 generated by the calibration signal generator 80 on the reproduction side. , increases if small, samples/
If the reference signal d held by the hold element 17 is larger than the calibration signal, it decreases. Therefore, the amplification degree of the regenerative amplifier 15 is automatically controlled so that the magnitude of the regenerated reference signal d is equal to the calibration signal.

The reproduction signal (d) output to the terminal 19 is transmitted to the reproduction amplifier 1.
5, the amplification degree is controlled in the same way as the reference signal d.

Comparing the reference signal d thus reproduced with a calibration signal,
By automatically controlling the amplification degree of the reproduction amplifier 15 depending on its size, the reproduction signal (a') obtained from the terminal 19 is always kept at a constant intensity ratio with respect to the recording signal (al) during recording. In other words, the recording/reproduction intensity ratio is always constant.This recording/reproduction intensity ratio is determined by the strength of the reference signal d of the reference signal generator 60 on the recording side and the calibration signal 2 of the calibration signal generator 3 on the reproduction side.
It is determined by the ratio of the strengths of , and if they are equal, the ratio is l
In other words, the strength of the reproduced signal is equal to the strength of the recorded signal.

Although the present invention has been described for channel 1 as described above, the recording/reproducing intensity ratio of channel 2 is also constant, and its value is equal to the recording/reproducing intensity ratio of channel 1. Therefore, when recording The relative relationship between the signal intensities of the recorded signal of channel 1 and the recorded signal of channel 2 is equal to the relative relationship of the signal intensities of the reproduced signal of channel 1 and the reproduced signal of channel 2 during reproduction.

[Brief explanation of drawings]

The drawing is a block diagram schematically showing an embodiment of the present invention. 10.20.30... Recording signal input terminal, 11
．． 21...Switch, 12,22.31...
... Recording amplifier, 13.23.32 ... Recording head, 14, 24.33 ... Playback head, 15.25 ... Amplification degree is controlled Possible regenerative amplifier, 16.26... switch, 17.27.
...Sample/hold element, 18.28...
... Differential amplifier, 19.29 ... Reproduction signal output terminal, 34 ... Regeneration amplifier, 60 ...
... Reference signal generator, 70 ... Magnetic tape, 8
0... Calibration signal generator.

Claims (1)

[Claims] means for interposing a signal strength reference signal in a time-division manner with the recording signal in a recording side circuit and recording it on a magnetic tape; means for detecting the reproduced reference signal in the reproduction side circuit; and the detected reference signal. means for comparing the intensity of the detected reference signal with the intensity of the calibration signal; and further, when the comparison results in that the intensity of the detected reference signal is greater than the intensity of the calibration signal, the amplification of the regenerative amplifier is reduced, and the detection A recording and reproducing method for a tape recorder, comprising means for controlling the amplification degree of the reproducing amplifier so as to increase the amplification degree of the reproducing amplifier when the strength of the reference signal obtained is smaller than the strength of the calibration signal. .