KR920005200B1 - Horizontal site control circuit for tv - Google Patents

Abstract

The horizontal position adjuster adjusts the position of frame right and left with a constant frame size. The adjuster includes a triangular wave generator (11) for generating triangular wave which period is adjusted according to flyback pulses, a horizontal oscillation circuit (12) for generating horizontal synchronous pulses by receiving the triangular pulses, an flyback transformer (10) for applying horizontal deflection voltage to a horizontal deflection coil, a delaying circuit connected between the flyback transformer and the triangular wave generator to delay the flyback pulses by a duration set by a user and to apply to the triangular wave generator (11), and a wave form modulator for mudulating the flyback pulses into rectangular pulses and for applying the delay circuit. The horizontal position of a frame is adjusted by the flyback pulse duration.

Description

Horizontal Position Control Circuit in Television

1 is a circuit diagram of the present invention.

2 is an operating waveform diagram of FIG.

* Explanation of symbols for main parts of the drawings

10: FBT 11: triangle wave generator

12: horizontal oscillation unit 13: horizontal driving unit

14,15 negative logic device 16-19 negative logic device

C1-C6: capacitor R1-R4: resistor

VR: Variable resistor

The present invention relates to a circuit for adjusting the position of the screen from side to side in a television.

Conventional technology for shifting the position of the screen from side to side in a general television is described in a patent application number filed under the name "last position adjustment circuit", which was filed in May 1988 by the present applicant. The adjustment circuit adjusts the horizontal position of the screen from side to side by adjusting the direction and magnitude of the deflection voltage applied to the deflection coil of the horizontal deflection portion by the change of the DC voltage.

The last position adjustment circuit has a problem in that each constant value affects the characteristics of a constant horizontal deflection according to the change of the DC voltage supplied to the horizontal deflection part. There was a problem that the screen size of the direction becomes large.

Accordingly, an object of the present invention is to provide a horizontal position control circuit that can adjust the position of the screen from side to side in a state of maintaining a constant size of the screen without affecting the characteristics of the horizontal deflection portion in the television.

According to the present invention for achieving the above object, there is provided a delay means for delaying the flyback pulse applied from the flyback transformer by a predetermined period to the triangular oscillator. Further, in order to smoothly operate the delay means, it is preferable to install auxiliary waveforms between the flyback transformer and the delay means for shaping the flyback pulse into an accurate square wave.

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

1 is a circuit diagram of the present invention, in a known television having a flyback transformer (hereinafter referred to as FBT) 10, a triangular wave oscillation unit 11, a horizontal oscillation unit 12, and a horizontal driving unit 13, Two negative logic elements (14, 15) and capacitors (C1, C2) connected between the FBT (10) and the line (4) to waveform-shape the flyback pulse, which is the output of the FBT (10), into a square wave. And a portion consisting of a resistor R1 corresponds to the waveform shaping means, and is connected between the waveform shaping means and the triangular wave oscillator 11 to delay the output of the waveform shaping means by the operator by setting the triangular wave oscillator ( 11) the portion consisting of the negative logic elements 16-19 and the capacitors C3-C6, three resistors R2-R4, and one variable resistor VR corresponds to the delay means.

2 is an operational waveform diagram for each part of FIG.

Therefore, FIG. 1, which is a circuit diagram of the present invention, will be described in detail with reference to FIG.

First, the FBT 10, the triangular wave oscillating unit 11, the horizontal oscillating unit 12, and the horizontal driving unit 13 will be described first. The FBT 10 outputs a deflection voltage to the horizontal deflection coil and corresponds to the interval between the syringes. Generate a flyback pulse and output it via line (1). The flyback pulse on the line 1 has a waveform as shown in FIG. A negative logic element 14 having one input terminal connected to the line 1 and the other input terminal connected to the connection point 4 is input through a connection point 4 of a flyback pulse on the line 1. A negative logic sum operation of the feedback input signal outputs a negative square wave as shown in FIG. 21 to the connection point 2. The capacitor C1 connected between the connection point 2 and the connection point 3 and the resistor R1 connected between the connection point 3 and the common supply potential Vcc are one differential circuit to the RC time constant. By setting the width of the pulse to be output on the connection point (4) is set equal to or slightly larger than the width of the flyback pulse.

At this time, the capacitor C1 and the resistor R1 differentiate the negative spherical pulses on the connection point 2 as shown in FIG. 22 and output them to the connection point 3 while connecting between the connection point 2 and the reference potential GND. The condenser C2 prevents a transient occurring in the rising portion of FIG. 21 during operation of the differential circuit. In addition, the negative logic element 15 in which both input terminals are commonly connected to the connection point 3 and the output terminal is connected to the connection point 4 has a high logic state when the potential on the connection point 3 becomes below the threshold voltage Vsh. Is output to the connection point 4, and a positive rectangular pulse is output as shown in FIG.

The two negative logic elements 14 and 15 described above, and the capacitor C1 and C2 and the resistor R1 are shaped as a Schmitt Trigger circuit, and the flyback pulse on the line 1 is applied to the 23rd. Waveform shaping is performed with a perfect square wave as shown in FIG. 23 to output to the connection point (4). That is, the waveform shaping means shapes the output as a perfect square wave even though the input waveform is somewhat distorted. The two negative logic elements 16 and 17, the capacitors C3 and C4, and the variable resistor VR are connected between the line 1 and the connection point 4 to act as waveform shaping means. As a circuit of the same type as the above, the pulse width control function of adjusting or reversing the pulse width of the conventional flyback pulse on the connection point 4 is controlled by adjusting the resistance value of the variable resistor VR. It will be described in detail as follows.

The negative logic element 15 which connects both the input terminal to the said connection point 4 and the connection point 7, and the output terminal to the connection point 5 is a normalized flyback as shown in FIG. The negative-back calculation of the flyback pulse whose pulse width is adjusted as shown in FIG. 26 on the pulse and the connection point 7 is performed by a negative logic to output a negative square wave as shown in FIG. The differential circuit composed of the capacitor C3 connected between the connection point 5 and the connection point 6 and the variable resistor VR connected between the connection point 6 and the reference potential GND is controlled by the viewer. The width of the pulse on the connection point 7 is adjusted by R and C time constants corresponding to the changed resistance value.

The capacitor C3 and the variable resistor VR differentiate negative pulses as shown in FIG. 24 to output a waveform of the form shown in FIG. 25 to the connection point 6, and the connection point 5 and the reference potential ( The capacitor C4 connected between the GNDs prevents a transient phenomenon of the differential circuit composed of the capacitor C3 and the variable resistor VR in the falling change portion of FIG.

In addition, the negative logic element 16 having the common connection between both input terminals connected to the connection point 6 and the output terminal connected to the connection point 7 has a thread in the waveform shown in FIG. 25 on the connection point 4 as one inverting buffer. While a signal above the hold voltage is input, an output in a low logic state is output to the connection point 7 to generate a negative square wave as shown in FIG.

And a capacitor C5 connected between the connection point 7 and the line 8 and a resistor R2 connected between the line 8 and the common supply potential Vcc, between the line 8 and the reference potential GND. The two resistors R3 and R4 and the capacitor C6 connected in parallel to each other are calculus mixed circuits, where the differential circuit having the condenser C5 and three resistors R2-R3 is connected to the connection point 7. As shown in FIG. 26, the derivative of the flyback pulse whose pulse width is adjusted is differentiated during the rise and fall of the pulse width, and is output to the line 8, and has the condensers C5 and three resistors R2-R4. The integrating circuit performs the function of integrating the differential waveform on the line 8, and the three resistors R2-R4 have a potential higher than the reference potential greater than the reference potential and smaller than the threshold potential of the logic element. Each serves as a potentiometer to maintain.

In addition, the negative logical elements 18 and 19 connected in series with the lines 9 and 8 are for performing a buffer function. The negative logical elements in which both input terminals are commonly connected on the line 8 are provided. Numeral 18 shows a low logic state and negative pulses during a waveform section equal to or greater than the threshold potential Vh among the calculus mixed waveforms shown in FIG. 27 on the line 8 as shown in FIG. A negative logic element 19 that generates a delayed flyback call and commonly inputs the output of the negative logic element 18 to both input terminals inverts the output of the negative logic element 18 to generate a delayed flyback call. A reproduction flyback pulse having a positive pulse as shown in 29 is output to the triangular wave oscillator 11 through a line 9.

The triangular wave oscillator 11 inputting the delayed flyback pulse from the line 9 generates a triangular wave delayed by a time T from FIG. 3 as shown in FIG. 12)

Then, the horizontal oscillator 12 generates a horizontal synchronous pulse by the output of the triangular wave oscillator 11 and outputs it to the horizontal driver 13. The horizontal driving unit 13 which inputs a horizontal synchronization pulse from the horizontal oscillation unit 12 controls the FBT 10 by the horizontal synchronization pulse to cause the FBT 10 to generate a horizontal deflection voltage and supply it to the horizontal deflection coil. do.

Also, it can be seen that when the triangle wave generator origin is delayed by the time T in contrast with FIGS. 30 and 31, the horizontal scanning start point can be delayed by the distance corresponding to the time T. Here, it can be seen that the detailed configuration of the waveform shaping means and the delay means can be variously changed and modified within the scope without departing from the basic definition of the present invention, and can be sufficiently implemented as other logic elements. Anyone who has can understand it.

As described above, the present invention has the advantage that the position of the screen can be adjusted horizontally without affecting the characteristics of the horizontal deflection portion and without expanding the horizontal axis of the screen.

Claims (2)

A horizontal deflection in accordance with the horizontal synchronization pulse applied from the triangular wave oscillation unit 11 for generating a triangular wave of a predetermined period in response to the flyback pulse applied and the horizontal oscillation unit 12 for generating the horizontal synchronizing pulse by inputting the generated triangular wave. A horizontal driving unit 13 for outputting a driving voltage for driving the FBT 10 generating a horizontal deflection voltage in response to the driving voltage of the horizontal driving unit 13, and applying the horizontal deflection voltage to a horizontal deflection coil; In the provided television, a flyback pulse applied between the FBT 10 and the triangular wave oscillator 11 is applied to the triangular wave oscillator 11 by delaying a flyback pulse applied from the FBT 10 by a predetermined period. And a horizontal means for adjusting the horizontal position of the screen by the delay period of the flyback pulse. 2. The apparatus according to claim 1, further comprising waveform shaping means connected to the delay means and the FBT (10) for shaping a flyback pulse applied from the FBT (10) into a square wave for application to the delay means. Horizontal position control circuit.

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