JPH0551985B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a tape recorder that plays back a tape on which a program, which is software used in a personal computer or the like, is recorded.

(b) Prior Art Recently, personal computers have become popular, but the programs used in such devices are recorded on commercially available cassette tapes, and when used, the programs recorded on the cassette tapes are transferred to a tape recorder. The data is played back and input into a computer.

(c) Problems to be Solved by the Invention After a program recorded on a cassette tape is played back, it is waveform-shaped and converted into a digital signal, but the phase of the signal recorded on the tape varies from company to company. be.

For example, as shown in FIG. 2A and B, in the case of the PWM method, the level 300 μs after the rise of the pulse is "1" when it is high, and "0" when it is low. Figure 2 A shows the case of positive phase, and Figure 2 B shows the case of reverse phase.As is clear from these figures, the phases of the two signals are different, so the data is in opposite phase. In the case of "0", misreading of data occurs by detecting the level of the adjacent bit.

In addition, as shown in Figure 3 A and B, in the case of the FSK method, when the pulse level changes once within a certain period of time after the pulse goes from low to high, when it changes to "0" twice Although it is set as “1”,
In this case, the phase shifts by 1/2 wavelength between the positive phase shown in FIG. 3A and the reverse phase shown in FIG. 3B, resulting in misreading of data.

The present invention aims to provide a tape recorder that solves the above-mentioned problems.

(d) Means for Solving the Problems The present invention provides a preamplifier circuit that receives a signal reproduced by a magnetic head that reproduces a signal recorded on a tape and amplifies the signal, and a preamplifier circuit that amplifies the signal. a phase circuit which receives a signal amplified by the positional amplifier circuit and has a first output terminal for extracting the input signal in a positive phase and a second output terminal for extracting the input signal in an opposite phase; A main amplifier circuit that receives a signal and amplifies the signal; and a main amplifier circuit that is inserted and connected between the output terminal of the phase circuit and the main amplifier circuit, and selects a signal of a different phase and inputs it to the main amplifier circuit. It consists of a phase changeover switch.

(e) Effect The present invention provides a phase circuit having terminals that can take out signals reproduced by a magnetic head in positive and negative phases, and by switching a phase changeover switch, the signals recorded on a tape can be changed. This makes it possible to extract a reproduced signal with a phase corresponding to the phase.

(F) Embodiment The circuit shown in FIG. 1 is an embodiment of the present invention. 1 is a magnetic head that operates as a playback head for reproducing signals recorded on tape T during playback operation and as a recording head for recording signals on tape T during recording operation; 2 for inserting a microphone plug; A micro jack, 3, receives a reproduction signal reproduced from the magnetic head 1 or a microphone signal input from the microphone jack 2, and a preamplifier circuit that amplifies the signal; 4, a preamplifier circuit that amplifies the signal; This is a main amplifier circuit to which an amplified signal is input and which amplifies the signal. Reference numeral 5 designates a phase circuit to which the signal amplified by the preamplifier circuit 3 is input, and is constituted by transistors 6, 7, etc., and has a first output terminal 8 and a first output terminal connected to the collector and emitter of the transistor 7, respectively. Two output terminals 9 are provided. The signals outputted from the first output terminal 8 and the second output terminal 9 are signals whose phases are shifted by 180 degrees from each other due to the characteristics of the transistor.

Reference numeral 11 denotes a headphone jack to which the signal amplified by the main amplifier circuit 4 is applied, into which a headphone plug is inserted when a headphone is used, and a connection cord plug used for connection with a computer when a computer is used. is configured to be inserted. 12 is a speaker to which the signal amplified by the main amplification circuit 4 is applied and emits the signal; 13, 14, 1;
Reference numerals 5 and 16 indicate recording/playback switching switches for switching circuits and the like constituting the tape recorder between a recording operating state and a reproducing operating state, and the illustrated state is the reproducing operating state.

Reference numerals 17 and 18 are mode changeover switches for switching the tape recorder between a normal playback mode, that is, a normal mode of playback of music, etc., and a computer mode of use, in which it is connected to a computer;
The illustrated state is a normal use state.

19 is a first circuit provided in the phase circuit 5 .
A phase changeover switch 20 selects the signal output from the output terminal 8 or the second output terminal 9 and guides it to the main amplification circuit 4, to which the signal amplified by the preamplification circuit 3 is applied and also A variable resistor that adjusts the signal level.

The tape recorder of the present invention is constructed as described above, and its operation will now be described. first,
The reproduction operation in the normal use state in which the recording and reproduction changeover switches 13, 14, 15, and 16 and the mode changeover switches 17 and 18 are in the illustrated states will be described.

If you perform a playback operation on the tape recorder in the state shown in the figure, the drive mechanism (not shown) etc. will be in a state for playback operation, and power will be supplied to each circuit to configure the playback operation state of the tape recorder. . Signals such as music recorded on tape T,
After being reproduced by the magnetic head 1, the signal is input to the preamplifier circuit 3 through the recording/reproducing switch 13. The reproduced signal input to the preamplifier circuit 3 is amplified and then applied to a variable resistor 20 to adjust its level. The playback signal whose level has been adjusted by the variable resistor 20 is input to the main amplifier circuit 4 through the mode changeover switch 17 and the recording/playback changeover switch 15, where it is amplified. The playback signal amplified by the main amplifier circuit 4 is applied to the speaker 18 through the recording/playback switch 16, the switch of the headphone jack 11, and the mode switch 18, and is emitted as sound. Therefore, the user can reproduce and listen to signals such as music recorded on the tape T by the sound output operation of the speaker 18. Furthermore, in such a state, if the headphone plug is inserted into the headphone jack 11, the reproduced signal can be reproduced and listened to by the headphone.

As described above, the playback operation is performed in the normal usage state, but next, the recording operation will be explained. When the user performs a recording operation, the recording/playback switch 1
3, 14, 15, and 16 are switched to the recording side, which is the opposite side to the illustrated state, thereby forming a recording state. A microphone signal inputted through the microjack 2 is inputted to a preamplifier circuit 3 through a recording/playback switch 13 and is amplified.
The microphone signal amplified by the preamplifier circuit 3 is input to the main amplifier circuit 4 through the recording/playback switch 15 and is amplified. The microphone signal amplified by the main amplifier circuit 4 is
A signal is applied to the magnetic head 1 which is in the state of performing a recording operation through the recording/reproduction changeover switch 16. Therefore, the microphone signal is recorded onto the tape T by the magnetic head 1.

As described above, recording and reproducing operations are carried out as a normal tape recorder.Next, the operation when connected to a computer will be explained. This operation is performed by using a tape on which a program has been recorded as tape T, inserting the plug of the connection cord into the headphone jack 11, and setting the mode changeover switches 17 and 18 to the computer on the opposite side of the diagram. This is done with the switch switched to the use side.

After the tape recorder is in this state, when the user performs a playback operation, the program signal recorded on the tape T is played back by the magnetic head 1. The program signal reproduced by the magnetic head 1 is input to the preamplifier circuit 3 through the recording/reproducing switch 13 and is amplified. The program signal amplified by the preamplifier circuit 3 is applied to the base of a transistor 6 constituting a phase circuit 5 .

In this way, the program signal is input to the phase circuit 5 , but in the state shown in the figure, the phase changeover switch 19 is in a state to output the signal output from the first output terminal 8 to the subsequent circuit. Therefore, the phase of the signal output from the phase circuit 5 becomes the same as the phase of the input signal.

The program signal output from the phase circuit 5 is input to the main amplifier circuit 4 through a phase changeover switch 19, a mode changeover switch 17, and a recording/playback changeover switch 15. The program signal input to the main amplifier circuit 4 is amplified and then sent to the headphone jack 1 through the recording/playback switch 16.
1. Therefore, the program signal is output to the computer through the plug of the connection cord inserted into the headphone jack 11, and the computer can perform a predetermined operation.

In this way, the output operation of the program signal recorded on the tape T to the computer is performed, but if the phase of the program signal recorded on the tape T is opposite, the reading operation of the computer is performed. This means that you will not be able to do so. In this case, it is sufficient to switch the phase changeover switch 19 to the opposite side from the state shown in the figure. When the phase changeover switch 19 is switched, the phase of the signal output from the phase circuit 5 becomes opposite to the phase of the input signal. Therefore, the phase of the program signal outputted to the computer through the plug of the connection cord inserted into the headphone jack 11 is also reversed to that before switching, and the reading operation to the computer is performed.

In this way, the program signal recorded on the tape T is output to the computer, and while this operation is being performed, the program signal amplified by the main amplifier circuit 4 is output to the computer by the resistor 2.
1 and the mode changeover switch 18, the signal is applied to the speaker 12 and the sound is emitted. Therefore, the user can confirm the output operation of the program signal to the computer. The volume in such a case is set by the resistor 21 to be an appropriate volume.

In this embodiment, the output signal of the preamplifier circuit 3 is input directly to the phase circuit 5 .
It can also be configured to input a signal whose level is adjusted by the variable resistor 20.

(G) Effects of the Invention The present invention provides a phase circuit having terminals capable of extracting signals reproduced by a magnetic head in positive phase and reverse phase, and by switching a phase changeover switch, recording can be performed on a tape. Since the reproduced signal can be extracted with a phase corresponding to the phase of the signal, the reading operation by the computer can be performed without any problem even if the phase of the program signal recorded on the tape is different.

[Brief explanation of the drawing]

Figure 1 is a circuit diagram showing one embodiment of the present invention, Figure 2 is a circuit diagram showing an embodiment of the present invention.
Figures A and B and Figures A and B of 3 are signal waveform diagrams for explaining the present invention. Explanation of main drawing numbers: 1...Magnetic head, 3...Preamplifier circuit, 4...Main amplifier circuit, 5 ...Phase circuit, 11...Headphone jack, 12...Speaker, 13, 14 , 15, 16...Recording/playback switching switch, 17, 18...Mode switching switch, 19...Phase switching switch.

Claims (1)

[Claims] 1. A magnetic head that reproduces the signal recorded on the tape, a preamplifier circuit that receives the signal reproduced by the magnetic head and amplifies the signal, and a signal amplified by the preamplifier circuit. a phase circuit having a first output terminal that receives the input signal and outputs the input signal in the positive phase, and a second output terminal that outputs the input signal in the opposite phase; a main amplifier circuit that amplifies the phase circuit; and a phase changeover switch that is inserted and connected between the output terminal of the phase circuit and the main amplifier circuit, and that selects a signal of a different phase and inputs it to the main amplifier circuit. recorder.