JPS61273739A - Double cassette type magnetic recording and reproducing device - Google Patents

Abstract

PURPOSE:To perform dubbing operation in a short time by rotating a recording- side cylinder motor according to head switching pulses to a reproducing-side deck so that the azimuth angle of the video head of a recording-side deck coincides with the azimuth angle of the video head of the reproducing-side deck. CONSTITUTION:Head switching pulses generated by the head switching pulse generating circuit 1s of the 1st deck P are phase-corrected by a monostable multivibrator 2u and inputted to a cylinder control circuit 2m through the lower contact of a switch SW 8. Information on the polarity (azimuth angle) of the video head of the 1st deck P is transmitted to the 2nd deck R by inputting said head switching pulses of the 1st video deck P to match the polarity (azimuth angle) of the video head of the 1st deck P with that of the 1st deck P. The cylinder control circuit 2m generates a signal for control with an FG signal which is frequency-divided to half, the switching pulses, and the head switching signal from the 1st deck P and inputs the signal to a gain control circuit 2n. Consequently, the time required for dubbing is shortened.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention essentially applies to two magnetic recording and reproducing devices (hereinafter referred to as VT
The present invention relates to a double cassette type magnetic recording and reproducing device capable of dubbing (transferring) and having the same function as that using the cassette type magnetic recording/reproducing device using the cassette R.

Conventional technology Conventional dubbing methods include: - Playback on the master deck, recording on the slave deck, taking the same amount of time to record as it took to record the original tape.

■A method of transferring data at a fairly high speed using a videotape printer (referred to as VTR).

There were two types.

Problems to be Solved by the Invention The above-mentioned method (■) allows for easy dubbing at low cost, but
There is a drawback that dubbing takes time just to play back the original tape (soft tape) for dubbing.

In other words, it takes an hour to dub a one-hour soft tape.

In addition, although the method (2) described above is high-speed, the VTR is very expensive, the running cost is very high, and the image quality is not much different from the method (2), so it is difficult to match the cost.

SUMMARY OF THE INVENTION In view of the above-mentioned problems, it is an object of the present invention to provide a double J set type VTR that is inexpensive, easy to use, and allows dubbing to be performed in a shorter time than conventionally.

Means to Solve the Problems The double cassette type magnetic recording/reproducing apparatus of the present invention has two tape drive mechanisms and electric circuits mounted on one frame, with one deck in the playback mode and the other deck in the recording mode. In this mode, the contents of a recorded tape are dubbed onto another tape, and the capstan motor and cylinder motor are rotated at the same rate of rotation, which is higher than the number of rotations during normal recording and playback, and the recording side The apparatus is characterized in that the recording side cylinder motor is rotated in response to the head switching pulse of the reproduction deck so that the azimuth angle of the video head of the deck matches the azimuth angle of the video head of the reproduction deck.

Operation With this structure, reproduction and recording can be performed at a constant magnification without changing the format of the J-V to be dubbed, and dubbing can be performed in a shorter time than conventionally.

Example Hereinafter, one embodiment of the present invention will be described based on the drawings.

The drawings show a magnetic recording/reproducing apparatus according to the present invention, and an example in which dubbing is performed at twice the speed will be explained here.

First, P in the upper half is the first deck in playback mode, and in the capstan system, it is the FG signal CAP of the main 1st busstan motor.
FG is waveform-shaped by the waveform shaping circuit 1a, divided by the 1/2 frequency dividing circuit 1b, and passed through the lower contact of switch SW1 (there are switches SW1 to SW9, but in double-speed dubbing mode, all of the lower contacts It passes through the contact. Also, during normal recording/reproduction, it passes through the upper contact.) Kitt=7 Enters the stun control circuit 1C. On the other hand, the control signal CTL read from the control head (not shown) is waveform-shaped by a waveform shaping circuit 19, and then frequency-divided by a 1/2 frequency dividing circuit 1h. The capstan control circuit 1 corrects the phase in step 11.
Enter C. A reference signal is further input to the capstan control circuit 1C from a reference signal source 1j. This 3
From the various signals, a control signal is created in the capstan control circuit 1C and inputted to the gain control circuit 1d.

This gain control circuit 1d is configured so that the gain (q) is twice the normal value when rotating at double speed according to a gain switching command. input to circuit 1e, capstan motor 1
Rotate f at twice the speed.

On the other hand, in the cylinder motor system, the cylinder motor system (hereinafter referred to as CYL FG) is waveform-shaped by the waveform shaping circuit 1, frequency-divided by the 1/2 frequency dividing circuit 1g, and then
It is input to the cylinder control circuit 1m via the lower contact point 3. The cylinder motor @ (CYL PF) has its waveform shaped by the waveform shaping circuit 19, the phase is corrected by the monomulti 1r, the head switching pulse is created by the head switching pulse creation circuit 1S, and the head switching pulse is divided by the 1/2 frequency dividing circuit 1t. and enters the cylinder control circuit 11Il via the lower contact of the switch SW4. A reference signal is input from the reference signal source 1j to the cylinder control circuit 111, and the cylinder control circuit 1111 outputs a cylinder control signal based on these three types of input signals and enters the gain control circuit 1m. This gain control circuit 111, like the above-mentioned capstan motor system, is configured so that the gain becomes twice the normal gain during dubbing at double speed according to a gain switching command. The output of the gain control circuit 1m is the motor drive circuit 10
and rotates the cylinder motor 1p at twice the speed.

In this way, the first deck P can play back a normal recorded tape in playback mode at twice the speed without changing the recorded format. However, at this time, the relative speed is twice that of normal recording/playback, so the signal processing circuits for video and audio signals must be changed accordingly.

Next, the second deck R (recording mode) is configured to be able to record at double speed.

First, we will discuss the J+11 Bustan series. The waveform is shaped by the FG multiplied signal waveform shaping circuit 2a of the capstan motor, then divided by the 1/2 frequency divider circuit 2b, and then enters the capstan control circuit 2C via the lower contact of the switch SW5.

A reference signal is inputted to the capstan control circuit 20 from a reference signal source 2u, and the capstan control circuit 20 receives a reference signal from a reference signal source 2u.
At C, a signal for capstan motor control is created using the above-mentioned 1/2 frequency-divided FG multiplied signal reference signal. This control output signal enters the gain control circuit 2d. This gain aI
The l11M1 circuit 2d is configured so that the gain becomes twice the normal speed when the rotation speed changes from normal mode to double speed.
The switching is performed by a signal from the 19-off M command. The output of the gain control circuit 2d is input to the motor drive circuit 2e, and the capstan motor 2r is
Controlled rotation at twice the speed. In addition, to write a control signal, the head switching pulse of the first deck P (playback mode) is phase-corrected with a monomulti 2h, and then amplified with an amplifier 2g via the lower contact of the switch SW9. Writing is performed from a control head (not shown). Next, the cylinder system of the second deck R is waveform-shaped by the FG double signal waveform shaping circuit 2 of the cylinder motor, and frequency-divided by the 1/2 frequency dividing circuit 2Q.
cylinder 1iIII via the lower contact of switch SW6.
I! One circuit is 2m long.

On the other hand, the waveform is shaped by a PG double signal waveform shaping circuit 2q, the phase is corrected by a monomulti 2r, a head switching pulse is created by a head switching pulse creation circuit 2S, and the frequency is further divided by a 1/2 frequency dividing circuit 2t. It enters the cylinder control circuit 2Il via the lower contact of the switch SW7. In this cylinder control circuit 211, the head switching pulse created by the head switching pulse creation circuit 1S of the first deck P (reproduction mode) is phase-corrected by the monomulti 2u and sent via the lower contact of the switch SW8. By inputting the head switching pulse of the first deck P, the information on the polarity (azimuth angle) of the video head of the first deck P is transferred to the second deck P.
The polarity (azimuth angle) of the video head of the second deck R is set to match that of the first deck R. The cylinder control circuit 2+1 creates a control signal using the G signal whose frequency is divided into 1/2, the head switching pulse, and the head switching signal from the first deck P, and this signal is sent to the gain control circuit 2m. The gain control circuit 2III is configured to double the normal gain when rotating at twice the speed, and this switching is performed by the gain switching command described above. The output of is input to the motor drive circuit 20, which rotates the cylinder motor 2p at twice the normal speed under control.In this way, the second deck R (recording mode) also rotates at twice the normal speed. capstan motor 2d
The cylinder motor 2p can be rotated under control, but since the relative speed of the video signal and audio signal is doubled, the signal processing circuit must be changed accordingly.

In addition, when performing normal recording/playback, switch SW
If you do everything from 1 to SW9 via the upper contact,
This will be possible as before. (However, the gain switching command is the 1u command in normal mode). 21 is a vertical synchronization signal separation circuit, 2
j is a waveform shaping circuit.

In the above embodiment, a case has been described in which dubbing is performed at a double magnification, but this need not be limited to double, and the capstan motor and cylinder motor may be rotated at the same magnification. However, considering the performance of the current video signal and audio signal processing 111j circuits, it is believed that approximately twice the amount can be realized at the lowest cost and with the simplest circuit. The magnification can be changed by dividing all the 1/2 frequency divider circuits in the figure by the desired magnification.

Effects of the Invention As described above, the double cassette type magnetic recording/reproducing main device of the present invention rotates the capstan motor and the cylinder motor at the same rate of rotation, which is higher than the number of rotations during normal recording/reproducing, and also allows the recording side deck to rotate Since the recording side cylinder motor is configured to rotate in response to the head switching pulse of the playback deck so that the azimuth angle of the video head matches the azimuth angle of the video head of the playback deck, the capstan motor and cylinder motor are An excellent effect can be obtained in that the time required for dubbing can be shortened by the amount of rotation at a constant magnification.

[Brief explanation of the drawing]

The drawing shows a configuration diagram of an embodiment of the double cassette type magnetic recording/reproducing apparatus of the present invention. P...first deck [reproduction side deck], R...second
Deck (recording side deck), 1 d, In, 2 d
, 2n - gain 11jtlO circuit, if, 2d...
・Capstan motor, 1b, 2p... Cylinder motor, 1s... Head switching pulse creation circuit, 1
1.2m...Cylinder control circuit

Claims (1)

[Claims] One or two tape drive mechanisms and electrical circuits are attached to one frame, and one deck is set to playback mode and the other deck is set to record mode, so that the contents of one recorded tape can be dubbed onto another tape. At the same time, the capstan motor and the cylinder motor are rotated at the same rate of rotation, which is higher than the rotation speed during normal recording and playback, and the azimuth angle of the video head of the recording deck is the same as the azimuth angle of the video head of the playback deck. A double cassette type magnetic recording and reproducing device configured to rotate a recording side cylinder motor in response to a head switching pulse of a reproducing side deck so as to match the head switching pulses of the reproducing side deck.