KR100191490B1 - VTR Switching Point Regulator - Google Patents

Abstract

The present invention relates to an apparatus for adjusting a switching point of a VTR that adjusts a switching point of the VTR while observing a pulse width signal and a state signal received by receiving an image signal and a head switching signal output from the VTR. Adjusting circuit (2) for receiving video signal (a) and head switching signal (b) output from VTR (1) and outputting pulse width signal (E) and status signal (J) for adjusting the waveform of these signals And a digital scope (3) for receiving the pulse width signal (E) output from the adjusting circuit (2), counting the number of pulses of the input signal, and digitally displaying the counter value, and the digital scope. Inspection control unit 4 for receiving the counter signal output from (3) and at the same time receiving the state signal (J) output from the adjustment circuit (2) to adjust the number of bits for the rotational speed of the motor (7) And, the inspection control unit The position controller 5 for setting the position of the adjustment bit of the motor 7 by the number of bits adjusted in (4), and the motor 7 according to the position of the adjustment bit set by the position controller 5. It is characterized by consisting of a drive unit 6 for driving.

Description

VTR Switching Point Regulator

1 is an overall block diagram of a switching point adjusting device of a VTR according to the prior art.

2 is an output signal waveform diagram of a VTR.

3 is an overall block diagram of a switching point adjusting device of a VTR according to the present invention.

4 is a detailed view of an adjustment circuit according to the present invention.

5 is an output waveform diagram at each position of FIG.

* Explanation of symbols for main parts of the drawings

1: VTR 2: control circuit

3: digital scout 4: inspection control

5: position control unit 6: drive unit

7: motor 10: amplifier

11: Offset part 12: Reference voltage adjusting part

13 comparison unit 14 oscillation protection unit

15: oscillation portion 16: latch portion

17: oscillator

The present invention relates to an apparatus for adjusting a switching point of a VTR, which adjusts a switching point of the VTR while observing a pulse width signal and a state signal which are received by receiving an image signal and a head switching signal output from the VTR.

In general, a switching point adjusting device of a conventional VTR uses a method of manually adjusting the switching point while receiving a signal output from the VTR from a digital scope and analyzing a waveform of the input signal.

As shown in FIG. 1 to FIG. 2, the conventional VTR adjusting device includes two signals output from the VTR 1, that is, the video signal a and the head switching shown in FIG. The signal b is directly input from the digital scope 3 and the waveform of the input signal is analyzed by the inspection control unit 4 to adjust the number of bits to be adjusted with respect to the rotational speed of the motor 7, and the position According to the adjustment bit set by the control part 5, it is comprised so that the said motor 7 may be adjusted via the drive part 6, and the switching point of VTR is adjusted.

However, the switching point adjusting device of the VTR configured as described above is adapted to receive the video signal a and the head switching signal b output directly from the VTR 1 directly to the digital scope 3. After analyzing in the digital scope (3), it takes about 6 seconds to manually adjust the digital scope (3), which leads to a problem of improving the productivity of the VTR, and precisely because the adjustment is performed manually. There was a problem that adjustment was difficult.

Accordingly, the present invention has been made to solve the above problems, and an object of the present invention is to observe the pulse point signal and the state signal outputted from the VTR and the video signal output from the VTR and output the switching point of the VTR. The present invention provides a switching point adjusting device for a VTR that can shorten the adjustment time, improve productivity, and at the same time make precise adjustment of the VTR.

In order to achieve the above object, the switching point adjusting device of the VTR according to the present invention receives an image signal and a head switching signal output from the VTR, and outputs a pulse width signal and a state signal for adjusting the waveform of these signals. A digital scope for receiving a pulse width signal output from the adjustment circuit, a counter for the number of pulses of the input signal, and digitally displaying the counter value, and a counter signal output from the digital scope. And a control unit for adjusting the number of bits for the rotational speed of the motor by receiving a status signal output from the adjusting circuit, and a position control unit for setting the position of the adjusting bits of the motor by the number of bits adjusted by the inspection control unit. And driving to drive the motor in accordance with the position of the adjustment bit set by the position controller. It is characterized by consisting of wealth.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

3 is an overall block diagram of the switching point adjustment device of the VTR according to the present invention, FIG. 4 is a detailed view of the adjustment circuit according to the present invention, and FIG. 5 is an output waveform diagram at each position of FIG.

In FIG. 3, reference numeral 1 denotes a VTR for outputting a video signal a and a head switching signal b, and reference numeral 2 denotes a video signal a and a head switching signal output from the VTR 1. b) is an adjustment circuit for receiving a pulse width signal (E) and a state signal (J) for adjusting the waveforms of these signals by receiving the b), and the adjustment circuit (2) is a video signal (output) output from the VTR (1). an amplifying section 10 for receiving a) and amplifying the input signal, an offset section 11 for setting a 200 kHz offset to a signal A input from the amplifying section 10, and The reference voltage adjusting unit 12 adjusts the reference voltage C in consideration of noise generated in the signal B input from the offset unit 11, and the voltage C output from the reference voltage adjusting unit 12. A comparator 13 which receives a voltage B output from the offset part 12 as an input and compares them with each other and outputs the difference. The oscillation protection unit 14 receives the head switching signal b outputted from the VTR 1, rectifies and inverts the stable pulse signal, and receives the signal output from the oscillation protection unit 14 to obtain a square wave. The oscillation unit 15 is composed of an oscillation unit 15 and a latch unit 16 which receives a signal output from the oscillation unit 15 and maintains the state of the input signal for a predetermined time.

(3) is a digital scope that receives the pulse width signal (E) output from the adjusting circuit (2) and counts the number of pulses and displays the counter value digitally, (4) is the digital scope (3). At the same time as receiving the counter signal output from the control circuit 2 receives the status signal (J) output from the adjustment circuit (2) is an inspection control unit for adjusting the number of bits for the rotational speed of the motor (7), The position control section sets the position of the adjustment bit of the motor 7 by the number of bits adjusted by the inspection control section 4.

(6) is comprised by the drive part which drives the said motor 7 according to the position of the adjustment bit set by the said position control part 5.

As shown in FIG. 3, an embodiment of the adjustment circuit 2 disposed between the VTR 1 and the digital scope 3 will be described in detail below.

4 to 5, reference numeral 10 denotes an amplifier which receives an image signal a output from the VTR 1 and amplifies the input signal, and reference numeral 11 denotes the amplifier 10. The offset unit 11 receives an amplified image signal A output from the input unit and sets an offset voltage (here, about 200 mA) to an input signal that changes according to the output signal. The offset unit 11 is the amplification unit 10. Field effect transistor (FET1) having a gate terminal connected to its output terminal and + 5V applied to its drain terminal, and diodes (D1, D2) connected in parallel to the source terminal of the field effect transistor (FET1). .

The non-inverting terminal (+) of the comparator COM of the comparator 13 receives a reference voltage signal adjusted through the variable resistor VR1 in consideration of noise generated in the signal input from the offset part 11. The reference voltage adjusting section 12 is composed of resistors R1, R2, variable resistor VR1, and capacitor C1.

Reference numeral 13 inputs the signal B output from the offset part 11 to the inverting terminal (-) of the comparator COM through the resistor R7 and the reference voltage output from the reference voltage adjusting part 12. A comparator which inputs the signal C to the non-inverting terminal (+) of the comparator COM, compares them, and outputs the difference. The comparator 13 is composed of a comparator COM.

14 is an oscillation protection unit which receives the head switching signal b outputted from the VTR 1 and rectifies and inverts it into a stable pulse signal F. The oscillation protection unit 14 includes a resistor R3; It consists of a capacitor C2, diodes D3 and D4 and a Schmitt trigger-inverter NG2.

Numeral 15 denotes a signal F output from the oscillation protection part 14 and input terminals 1B and 2 of the oscillator 17. The oscillator receives the input from the oscillator and oscillates the square wave pulse signals G and H to the output terminals 1Q and 2Q. The oscillator 15 includes an oscillator 17, resistors R5 and R6, and capacitors C3 and C4. Consists of Here, in the input terminal 18 of the oscillator 17, a high level signal among the output signals of the oscillation protection unit 14 is input, and the input terminal 2 ) Is a low level signal.

16 is a latch unit for receiving the square wave pulse signals G and H output from the oscillator unit 15 and maintaining the state of the input signal for a predetermined time. The latch unit 16 is a flip-flop 18. ) And Schmitt trigger inverter (NG3).

The following describes the effect of the switching point adjustment circuit of the VTR configured as described above.

As shown in FIGS. 4 to 5, the adjustment circuit 2 receives an image signal a output from the VTR 1 and converts the input signal into an operational amplifier OPA of the amplifier 10. When the amplification is performed, a pulse signal A represented by the waveform of FIG. 5A is output, and Δt indicates a time interval of the video signal output from the VTR 1.

The pulse output signal A output from the amplifier 10 passes through the field effect transistor FET1 and the diodes D1 and D2 of the offset unit 11 to generate an offset of 200 μs. The pulse signal B, which is represented by a waveform of), is output, and the pulse output signal B is input to the inverting terminal (-) of the comparator COM through the resistor R7.

In addition, in consideration of noise generated in the signal input from the offset unit 11, the reference voltage adjusting unit 12 including the capacitor C1, the resistors R1 and R2, and the variable resistor VR1 is adjusted. By outputting a pulse signal (C) represented by the waveform of Figure 5 (c), the pulse output signal (C) is input to the non-inverting terminal (+) of the comparator (COM).

In the comparator COM of the comparator 13, the reference voltage signal C output from the reference voltage adjusting unit 12 and the pulse output signal B output from the offset unit 11 are input. When these signals are compared by the comparator COM and the difference is outputted, a pulse signal D represented by the waveform of FIG. 5 d is output, and the pulse output signal D is a Schmitt trigger-inverter ( The pulse signal E, which is inverted through the NG1 and represented by the waveform of FIG. 5E, is output. The waveform E of the output signal is input to the digital scope 3 as a pulse width signal of the video signal a output from the VTR 1.

In addition, another signal output from the VTR 1, that is, the head switching signal b is input to the oscillation protection part 14 through the resistor R8, and the oscillation protection part 14 receives the input signal. Rectified into a stable pulse signal, the rectified signal is inverted through the Schmitt trigger-inverter NG2 to output a pulse signal F represented by the waveform of FIG. 5 (f), and the pulse output signal F The high level signal is input to the input terminal 1B of the oscillator 17, and the low level signal is input to the input terminal 2. ) Is entered. The oscillator 17 has the oscillator 17 according to a time constant determined by the resistor R5 and the capacitor C3 connected to the terminals 14 and 15 when the pulse output signal F is at a high level. Outputs a pulse signal (G) of the waveform shown in FIG. 5 (g) from the output terminal (1Q) of the terminal, and when the pulse output signal (F) is at a low level, According to the time constant determined by the resistor R6 and the capacitor C4, the output signal 2Q of the oscillator 17 outputs the pulse signal H having the waveform shown in FIG.

The pulse output signals G and H are rectified through the diodes D5 and D6, respectively, and synthesized into a pulse signal I represented by the waveform of FIG. 5 (i) to flip the flop 18 of the latch unit 16. Is input to the terminal (D). At this time, the pulse signal D output from the comparator 13 is input to the clock terminal CK of the flip-flop 18, and when the input signal D is high, the flip-flop ( 18 output stage ( Outputs a low signal to the output signal of the flip-flop 18 when the pulse signal D is low. Outputs a high signal.

Thereafter, the output terminal of the flip-flop 18 The signal output from the N-) is inverted via the Schmitt trigger-inverter NG3 to output the state signal J represented by the waveform of FIG. The pulse output signal J is a state signal of the head switching signal b output from the VTR 1 and is output to the inspection control unit 4 which adjusts the number of bits for the rotational speed of the motor 7. It is to adjust the switching point of 1).

As described above, according to the switching point adjusting device of the VTR according to the present invention, the video signal a and the head switching signal b outputted from the VTR 1 are received and the pulse width of these signals is received. By constructing the adjustment circuit 2 capable of outputting the signal E and the status signal J, the time for adjusting the switching point of the VTR 1 can be shortened, so that the productivity of the VTR can be improved. Since the adjustment process of the switching point is made automatically, it is possible to make precise adjustments, thereby producing an excellent VTR of vivid image quality.

Claims (2)

An adjustment circuit for receiving a video signal and a head switching signal output from the VTR and outputting a pulse width signal and a state signal for adjusting the waveform of these signals, and a pulse width signal output from the adjustment circuit. A digital scope that counts the number of pulses and digitally displays this counter value, and a bit about the rotational speed of the motor by receiving a counter signal output from the digital scope and a status signal output from the adjusting circuit. An inspection control unit for adjusting the number, a position control unit for setting the position of the adjustment bit of the motor by the number of bits adjusted by the inspection control unit, and a driving unit for driving the motor according to the position of the adjustment bit set by the position control unit. Switching point adjusting device of the VTR, characterized in that consisting of. The control circuit of claim 1, wherein the adjustment circuit comprises: field effect transistors (FET1) and diodes (D1, D2) for setting an offset voltage to a signal input from an amplifying unit that receives and amplifies the image signal output from the VTR, and a reference; A resistor (R1, R2), a variable resistor (VR1) and a capacitor (C1) for adjusting the voltage, a comparator for comparing the reference voltage and the offset voltage and outputting the difference, and a head switching signal output from the VTR. An oscillation protection unit which rectifies and inverts the inputted signal into a stable pulse signal, an oscillator which receives the signal output from the oscillation protection unit and oscillates a square wave, resistors R5 and R6 and capacitors C3 and C4 and the square wave signal Device for adjusting the switching point of the VTR, characterized in that consisting of a flip-flop and Schmitt-trigger inverter to receive the input and maintain the state of the input signal for a predetermined time.