JPS5827371Y2 - Tape recorder tape characteristic detection and setting device - Google Patents

Description

[Detailed description of the invention] This invention relates to a tape characteristic detection and setting device for a tape recorder that is capable of reliably setting the bias value button and equalizer value most suitable for the tape used in a two-head tape recorder. 0 In order to achieve better recording and reproduction for a tape recorder, it is very important to apply a recording bias suitable for the tape being used and to set an appropriate recording equalizer.

For this reason, tape recorders (tape decks) are equipped with recording bias and recording equalizers that can be arbitrarily set at two to three positions.

However, there are many different types of tapes on the market, including those with different standards such as normal, chrome, and ferrichrome, as well as tapes of the same type that are manufactured by different manufacturers and tapes such as C-30, C-60, etc. Each tape has its own unique recording characteristics, such as the thickness of the tape base due to the different lengths.

Therefore, it is not possible to deal with the tapes available on the market by adjusting the bias and equalizer in only 2 to 3 positions, and the current situation is that tapes are not being used to the fullest advantage of their tape characteristics.

Therefore, it is necessary to make it possible to set the bias settings steplessly on the tape recorder side, and also to be able to reliably determine the recording characteristics of the tape from the recording results and set the most suitable bias value and equalizer value. desired.

To do this, for example, you can set up a 3-head system, record a specific frequency signal while changing the bias value, play back the recording state almost simultaneously using the playback head, display this state on a meter, etc., and determine the optimal bias value. It is conceivable to make it distinguishable.

However, in the case of a cassette tape recorder (deck), the three-head configuration is due to problems with the setting position of each head and tape running characteristics, the azimuth relationship between the recording head and playback head depending on the cassette half used, and manufacturing issues in the case of a combination head. There are major difficulties such as problems and costs.

This idea was made taking these points into consideration, and 2.
Tape characteristic detection for tape recorders that can be applied to head configurations by pressing a button, and can determine and set the recording bias and recording equalizer according to the recording characteristics of any tape, allowing recording to make the most of the tape. A setting device is provided.

An embodiment of this invention will be described below with reference to the drawings.

As shown in FIG. 1, a bias oscillator 1 is connected to a recording/reproducing switch 5 via a bias adjuster 2, a capacitor 3, and a resistor 4 in series, and a parallel circuit of a coil 6 and a capacitor 7. and is connected to the amplifier 8.

The pre-record/re-changeover switch 5 is, for example, a slide switch whose common contact is connected to the recording/reproduction head 9, and the other contact is connected via an amplifier 10 to variable resistors 11 and 12, respectively.

The curved end of this variable resistor 11.12 is grounded, and the slider is connected to each contact piece of the changeover switch 13.14.

A changeover contact of this changeover switch 13 is connected to a fixed contact of the other changeover switch 14, and a common contact of this changeover switch 14 is connected to an amplifier 15.

The output end of this amplifier 15 is connected to a variable resistor 16.17, the other end of each variable resistor 16.17 is grounded, the slider of the variable resistor 16 is connected to the output end of the amplifier 8, The slider of the variable resistor 17 is connected to a reproduction amplifier (or to a line output terminal if it is a deck).

Further, the output terminal of the amplifier 15 is connected to an amplifier 18, and the output terminal of the amplifier 18 is connected to a meter 19 serving as a first display device and also to a differential amplifier 20.

The output terminal of this differential amplifier 20 is connected via an adjustment circuit 21 and a drive circuit 22 to a second display device 23 made of a light emitting element.

The amplifier 18 is provided with a switch 24 for adjusting meter sensitivity.

On the other hand, the fixed contact of the changeover switch 13 is connected to a slider of a variable resistor 25, one end of which is grounded, and the other end connected to the output end of a test oscillator 26.

This oscillator 26 is connected to the regulator 2 via a pause switch 27, a test switch 28, and a tape select switch 28.
9, and this regulator 30 is also connected to a play switch 32 via a delay circuit 31.

Further, the output terminal of the test oscillator 26 is connected to a lamp 34 via a standby circuit 33 and to a lamp 36 via a start lamp circuit 35.

A counter zero reset switch 37 is connected to this start lamp circuit 35.

The configuration is basically like this, but the detailed configuration will be explained below.

First, in the tape selection circuit, as shown in FIG. 2, a changeover switch S11 having normal and chrome positions has diodes 38 and 39 connected to its fixed contacts at the chrome position, and one diode 38 is connected to the changeover switch 52-. It is connected to the fixed contact piece d which is the chrome position 1, and is also connected to the movable contact piece d of the changeover switch S22.

The fixed contact piece C of this changeover switch 52-2 is the fixed contact piece bi which is the normal position of the changeover switch 51-1.
- and connected to the movable contact piece d of the changeover switch 52-1,
Furthermore, it is connected to the movable contact piece of the equalizer switching switch S3.

The fixed contact piece in the chrome position of this changeover switch S3 is connected to the chrome side of the equalizer circuit, while the fixed contact piece in the normal position is connected to the normal side of the equalizer circuit.

A fixed contact piece of the changeover switch S3 that is in the chrome position is connected to the diode 39.

Further, the remaining fixed contact piece of the changeover switch 52-2 is connected to the bias oscillator 1 portion.

Here, the bias oscillator 10 section will be explained in detail. As shown in FIG. Ru.

The collector and emitter of the transistor 40 are connected to the changeover switch 52-3i- through resistors 41 and 42, respectively.
and a fixed contact piece of the changeover switch S4, and a capacitor 43 is connected between the fixed contact piece of the changeover switch S4 and the common contact piece.

The connection point between this capacitor 43 and the resistors 41 and 42 is further connected to the base of the transistor 40 via a resistor 44, and this base is grounded via a capacitor 45 and connected to the power supply via a resistor 46. .

Also, the output terminal of the bias oscillator 1 is connected to the selector switch 52-4.
One fixed contact piece of this selector switch 52-4 is connected to the bias adjuster 2.

The remaining fixed contacts of the changeover switch 52-4 and the slider of the bias regulator 2 are connected to capacitors 3A and 3B, respectively.
, are connected to the recording/reproducing head 9 via resistors 4A and 4B in series.

Also, to explain the recording level setting button and the recording equalizer section, the sliding piece of the variable resistor 16 inserted into the recording signal line is connected to the changeover switch 52 through the resistor 47.
It is connected to the movable contact piece d and the fixed contact piece a of No. 5, and also to a variable resistor 48 for level adjustment.

The other end of this variable resistor 48 is grounded, the sliding piece is connected to the fixed contact C of the changeover switch S25, and the remaining fixed contact of this changeover switch 52-5 is connected to the amplifier 8 via the capacitor 49. connected to.

A recording equalizer circuit is also configured at the input end of this amplifier 80 via a capacitor 50.

A series circuit of capacitors 51 and 52, coils 53 and 54, and diodes 55 and 56 are connected in parallel to the other end of this capacitor 50, and these diodes 55 and 56 are connected to the movable contacts of changeover switches S2-6 and S2-7. Connected to piece d.

Fixed contacts a and b of the changeover switches S 2-6 and S 2-7 are grounded via resistors 57 and 58, and the remaining fixed contacts C are connected to a variable resistor 59.

The other end of this variable resistor 59 and the slider are grounded.

Regarding the display part, as shown in FIG. is connected to the display device 23 of.

The fixed contact pieces S and C are the movable contact pieces d1 of the changeover switch 65.
It is connected to a button and one end of each variable resistor 2, 59 for recording bias adjustment and recording equalizer adjustment, respectively.

A light emitting diode 66 is connected between the fixed contact piece of the changeover switch 65 and ground, and the slider of the variable resistor 2.59 is connected to the fixed contact piece b v of the changeover switch 69 via the light emitting diode 67.68, respectively. connected to c.

The movable contact piece d of the changeover switch 69 is further connected to the changeover switch 7.
This changeover switch 70 is connected to the fixed contact pieces a and b of 0.
The movable contact piece d is grounded.

The standby/start display circuit uses a flip-flop circuit 70 as shown in FIG. A switch 72 interlocking with a tape counter is connected between the terminal and the ground so that a test signal is guided to the set terminal.

FIG. 6 is an example of a panel surface of a tape recorder according to the present invention.

A cassette storage section 103 is provided in a part of the front panel 102 of the cabinet 101.
An operation button 104 is arranged below.

Two level meters 81 and 82 are arranged in parallel on the sides of the cassette storage section 103.
A light emitting diode 80 for displaying recording is provided between the two, and equalizer and bias switching knobs 105 and 106 are provided below one of the level meters 81, and a memory device is provided between this knob 105 and the cassette storage section 103. A counter 87 is provided.

Light emitting diodes 34 and 36 for displaying standby and start are provided below the memory counter 87.

Also, equalizer and bias adjustment knobs 88, 89 connected to variable resistors 59, 2 are provided below the switching knobs 105, 106, and level adjustment knobs 88, 89 are connected to variable resistor 48 below the light emitting diode 36. knob 90
is provided.

Also, music knobs 107, 108, 109 such as a line output adjustment knob are provided in parallel with the knobs 90.88.degree. 89.

Further, below the level meter 82, a chief switch knob 110 and a light emitting diode 6L62 for displaying bias and equalizer are provided.

Note that 83 is a pause button. In the above configuration, the operation will be described. A tape is loaded, each recording/reproduction switch is set to the recording side, and the output of the test oscillator 26 is guided to the head 9.

That is, switches 5 and 14 are set to the recording side, and switch 13 is set to the recording side.
, 52-4 are set to the fixed contacts (C side), the recording bias current is guided to the head 9 and the test signal oscillator 26
A test signal from the head 9 is led to the head 9 via amplifiers 15 and 8, and this test signal is recorded.

This recording is performed while changing the bias stepwise, and at the same time a control signal corresponding to the stepwise change in the recording bias is generated, and this is also recorded on the tape.

This control signal can of course be formed directly from a change in the bias value, or may be formed using various methods such as generating a pulse every predetermined rotation in relation to the rotation angle of the bias adjustment knob 88, although this is not shown. .

For example, when changing the recording bias in steps, the bias adjustment knob 88 is made into a clip-stop type, and a control signal such as a pulse is generated at each click stop point, and this is recorded at the same time as the test signal. do it.

Next, each recording/reproducing switch is switched to the playback side, and when the switch 13 is set to the fixed contact side, the test signal reproduced by the head 9 is amplified by the amplifier 10.15, and then passed through the variable resistor 17 to the subsequent stage. At the same time, the control signal is amplified by an amplifier 18 to drive a meter 19, which is a first display device, and the control signal that is reproduced at the same time is sent to a counting circuit 21 via an amplifier 20, where the stepwise change in bias is counted. be done.

The driver circuit 22 operates according to this count, and drives the second display device 23 having, for example, seven segments.

In other words, if the recording bias is in the third stage, three light emitting diodes are turned on or the display is digitally displayed.

In this way, the test signal level is displayed on the meter 19, which is the first display device, and the recording bias value is displayed on the second display device 23, so that the optimal recording of the sample tape can be determined from both displays. Bias value can be read.

For example, 333H2 (or IKH2) as a test signal
If we generate two frequencies alternately, 10KH2 and 10KH2, and record and reproduce the recording bias while changing the recording bias m as described above for each frequency, then By reading the level of the display device 23 of No. 2, it is possible to know the appropriate recording bias value over almost the entire frequency range.

Conversely, it is also possible to set the value biased towards one frequency, and it is possible to obtain an arbitrary frequency characteristic depending on the recording source and the like.

Without recording two frequencies alternately as described above,
Mix and record at the same time, separate this during playback,
The optimum bias value can be detected more reliably by providing two meters and two display sections and displaying the recording level and recording bias simultaneously and in parallel.

Furthermore, it is convenient to display the output level on one meter and the bias current value on the other meter, as it can be similar to measuring the bias characteristics of a tape.

When adjusting the recording equalizer, set the tape test to the recording equalizer side and perform the same operation as described above to obtain the optimum equalizer value.

That is, the changeover switch 52-6.52 in FIG.
-7 are respectively set as fixed contacts, and in this state, the variable resistor 59 is varied in steps and a test signal and a control signal corresponding to the change in the equalizer are recorded.

This control signal is also formed in the same manner as the recording bias.

Then, during playback, the output level is displayed on the meter 19 of the first display device in the same way as when adjusting the recording bias, and the variable state of the recording bias is displayed on the second display device 23 using a control signal. The optimum recording equalizer value can be read, and by setting the variable resistor 59 to that value, the optimum recording equalizer value can be obtained.

Of course, the recording equalizer value can also be set to a desired value depending on the recording source.

Incidentally, in the case of either the recording bias or the recording equalizer, when detecting the optimum value, the tape selector is set to the normal or chrome position depending on the tape type, and recording/reproduction is performed.

As described above, the device of this invention can read the characteristics of both the recording bias and recording equalizer of the tape being used, and determine the most suitable recording bias value for each tape.
It is possible to set the recording equalizer value and perform good recording and reproduction.

In particular, this recording bias and recording equalizer characteristic detection is
Since it can be applied to head-type tape recorders, it can be applied not only to tape recorders that use open reel, but also to tape recorders that use open reel.
This invention can also be applied to cassette tape recorders in which it is difficult to have a three-head configuration due to various reasons, and has a significant effect on cassette tape recorders.

Here, an explanation will be given of the operating procedures regarding the recording bias of the tape recorder, reading the characteristics of the recording equalizer, and setting.

(1) Adjust the tape selector (knob 106) (AD
J).

This connects the recording bias and recording equalizer circuits to the adjusting variable resistors 2 and 59, respectively.

(2) Set the tape test knob 110 to the bias position.

This brings the recording bias circuit into an adjustable state.

(3) Put the other circuits into the recording state and wait for the start lamp 36 to light up.

At this time, unless the following state is set, the start lamp 36 will not light up and will stop after a certain period of time has elapsed.

(b) When the pause remains in the recording state (the switch 37 is off and the light emitting diode 83 lights up) (b) Of course, when the tape test J rADJ J is not in the correct position, If the tape counter 87 is not reset to "O" when the j knob 89 is not set to "0" (the variable resistor 2 is not at O and the light emitting diode 68 lights up), the switch is turned off. 37 is off) above (A) to (If the bow position is not set, each of the light emitting diodes 83.84° and 85.86 lights up as described above.

(4) When the start lamp 36 lights up, “BIAS AD
Turn JJ (knob 89) sequentially at appropriate intervals from 0 to 10 to stop.

Recording should be automatically canceled at the "stop" position. 0 (5) Press the "rewind button" to rewind the tape.

When the memory counter 87 is at the position of ``1999'', the rewinding is stopped by the memory.

(6) Next, play the tape and read the output characteristics of the bias change using the meter 19 of the first display device.

At this time, the numbers corresponding to the scale of the bias ADJJ knob 89 during recording are displayed on the second display device 23, so
Adjust the bias ADJJ knob 89 to the desired bias value.

(7) After setting the bias, set "tape test" to "recording equalizer (RECEQ) J" and record using the same operation as when using the above recording bias.

At this time, the "Tep Selector" is set to normal (NOR) or chrome (Cr02) depending on the tape used.

(8) Reproduce this test recording section and read the recording state on the meter 19 of the second display device.

At this time, display I KHz on the L channel side of the stereo level meter and 10 KHz on the R channel side, and adjust the scale of the RECEQADJ J knob 88 to the desired frequency characteristics in the same way as when setting the recording bias.

(9) At this time, the display of the playback level on the IKHz side is meta-
The only reading that is blurred from the OVU display is “LEVEL”.
By adjusting the ADJJ knob 90, the recording standard level can be adjusted.

By recording and reproducing test signals in this way, it is possible to set the recording bias value and recording equalizer value to appropriate values, but this is not limited to manual operation, and the optimum bias value can be automatically set during playback. It is also possible to automatically detect the bias value and automatically set the optimum bias value according to the detected value.

As described above, according to this invention, it is possible to reliably detect the characteristics of the recording bias and recording equalizer of the tape used in a two-head tape recorder, and to set the recording bias and recording equalizer to the most suitable values. Accordingly, it is possible to provide a tape characteristic detection and setting device for a tape recorder that enables recording and reproduction that makes the most of the characteristics of the tape.

[Brief explanation of the drawing]

FIG. 1 is a wiring diagram showing a tape characteristic detection and setting device for a tape recorder according to an embodiment of the invention, FIG. 2 is a specific circuit diagram of the tape select switch portion of the tape characteristic detection and setting device shown in FIG. 1, and FIG. Figure 3 a and b are specific circuit diagrams of the recording bias adjustment unit and recording equalizer adjustment unit of the tape characteristic detection and setting device shown in Figure 1, and Figures 4 and 5 are the tape characteristic detection circuit diagrams shown in Figure 1. A wiring diagram showing display circuits of various parts of the setting device, and FIG. 6 is a perspective view showing a cassette tape recorder in which the tape characteristic detection and setting device shown in FIG. 1 is mounted. 1...Bias oscillator, 2...Variable resistor for bias adjustment, 3...Capacitor, 4...
...Resistor, 5゜14...Recording/reproduction switch, 6...Coil, 7...Capacitor, 8...Amplifier, 9. ...Recording/playback head,
10... Amplifier, 11, 12... Variable resistor, 13... Changeover switch, 15, 18...
...Amplifier, 19...Meter (first display device), 20...Amplifier, 21...
・Count circuit, 22...Driver circuit, 23
...Second display device, 24...Selector switch, 25...Variable resistor, 26...
・Test signal oscillator, 27, 28. 29... Changeover switch, 30... Variable resistor, 31...
... Delay circuit, 32... Changeover switch, Sl
-1,52-1,52-3゜52-4.52-5.5
2-6, 52-7... Changeover switch, 38, 3
9...Diode, 40...Transistor, 47...Switch, 48...Variable resistor for adjusting recording level, 51, 52...・Capacitor, 53, 54... Coil, 55, 56
...Diode, 5, 7, 58...Resistor, 59...Variable resistor for adjusting recording equalizer, 60.63, 69°70...Switching Switch, 71...Flip-flop circuit, 72...
...Switch, 61, 62, 66°67.68...
...Light emitting diode, 80.83. 84.85.86... Light emitting diode, 81
. 82...meter, 87...tape counter, 88...recording equalizer adjustment knob,
89... Song recording bias adjustment knob, 9o...
・Level adjustment knob.

Claims (1)

[Scope of utility model registration request] A test signal oscillator that generates a test signal that is selectively applied to the head, and a control signal that changes a recording bias value and a recording equalizer value when recording this test signal and simultaneously generates a control signal corresponding to the change in the recording bias value and recording equalizer value. a first display device that displays the test signal playback output level during playback; and a second display device that simultaneously displays changes in the recording bias value and the recording equalizer value by playing back the control signal. A tape characteristic detection and setting device for a tape recorder, which detects the recording characteristics of the used tape based on the displays on the first and second display devices and sets the recording characteristics to a required value.