JP3000607U - Vertical deflection circuit for CRT - Google Patents

Abstract

(57) [Summary] [Object] To provide a vertical deflection circuit of a CRT capable of easily adjusting the position of a vertically configured screen. [Configuration] A DC bias for adjusting the screen position in the vertical direction of the screen is added to the feedback side of the vertical deflection coil via a variable resistor to adjust the amount of feedback, thereby continuously adjusting the screen position in the vertical direction. It is a vertical deflection circuit of a CRT provided with a bias circuit.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a vertical deflection circuit of a CRT that can easily adjust the vertical position of a television monitor screen or the like.

[0002]

[Prior art]

 FIG. 2 is a circuit block diagram showing the configuration of a conventional vertical deflection circuit of a CRT in a television device. In the figure, reference numeral 1 is a deflection circuit including a sync separation circuit, a vertical oscillation circuit, and a horizontal oscillation circuit (not shown). 1a is a sync separation circuit for separating a vertical synchronous signal from a television video signal input, 1b is a vertical oscillation circuit having a multivibrator circuit in which an oscillation loop is formed by feedback from an output stage, 1c is a vertical oscillation circuit 1b. A sawtooth wave generator that generates a sawtooth wave based on the output, 1d is a vertical drive circuit that drives a vertical amplification transistor 2 based on the output of the sawtooth wave generator 1c, and 2a is a vertical amplification transistor Resistors 3 and 4 connected to the collector terminal of 2 are a pair of vertical output transistors forming a class B push-pull circuit. Reference numeral 5 is a vertical deflection coil (vertical deflection yoke), 6 is a capacitor connected in parallel to the vertical deflection coil 5, and 7 is a resistor.

The position of the vertically configured screen in such a vertical deflection circuit is adjusted by adjusting the deflection yaw.

[0004]

[Problems to be solved by the device]

 The position adjustment of the vertical component screen in the conventional vertical deflection circuit is performed as described above.Therefore, by adjusting the positions of the deflection yoke and the purity magnet, it is possible to correct the convergence and the color purity of the center of the screen. It was necessary to readjust the image, and it was not easy to adjust the position of the composition screen in the vertical direction.

The present invention has been made to solve the above problems, and an object of the present invention is to provide a vertical deflection circuit of a CRT that can easily adjust the position of a vertically configured screen. To do.

[0006]

[Means for Solving the Problems]

 A vertical deflection circuit for a CRT according to the present invention is a vertical deflection circuit for a CRT that applies a sawtooth deflection current to a vertical deflection coil to perform vertical deflection of a screen. The feature is that a DC bias adjusting means for adjusting the screen position in the direction is provided. Further, the DC bias adjusting means is a DC bias circuit that superimposes a feedback voltage on the feedback side through a variable resistor, and is characterized in that the screen position can be continuously adjusted in the vertical direction.

[0007]

[Action]

 In the vertical deflection circuit of the CRT according to the present invention, a DC bias adjusting means for adjusting the screen position in the vertical direction of the screen, that is, a DC bias is applied to the feedback side of the vertical deflection coil, that is, a DC bias is applied via a variable resistor so that the feedback amount is increased. Adjusted to allow continuous and easy adjustment of the vertical screen position.

[0008]

【Example】

 An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a circuit block diagram showing a configuration of a vertical deflection circuit of a CRT of this embodiment. In FIG. 1, parts that are the same as or correspond to those in FIG. 2 are assigned the same reference numerals and explanations thereof are omitted.

Reference numeral 11 is a variable resistor, 12 is a fixed resistor connected between one fixed terminal of the variable resistor 11 and the power supply line, and 13 is connected between the other fixed terminal of the variable resistor 11 and the ground line. It is a fixed resistor. The sliding terminal of the variable resistor 11 is connected to the feedback side of the vertical deflection coil 5. The fixed resistor 12, the variable resistor 11 and the fixed resistor 13 are connected in series to form a DC bias circuit 14 for dividing the power supply voltage and applying a DC bias to the feedback side of the vertical deflection coil 5.

Next, the operation will be described. In order to maintain good color purity, the apparent center of deflection must match the center of exposure on the phosphor screen, so the vertical position of the composition screen is adjusted while maintaining this state. Therefore, the potential difference between the power supply line and the ground line is divided by the series circuit of the fixed resistor 12, the variable resistor 11 and the fixed resistor 13, and the voltage is divided from the sliding terminal of the variable resistor 11 to the feedback side of the vertical deflection coil 5. Apply DC bias.

Then, the amount of feedback in the vertical deflection circuit is continuously adjusted by the position of the sliding terminal of the variable resistor 11 to change the position of the constituent screen in the vertical direction. Therefore, when adjusting the position of the configuration screen in the vertical direction, it is not necessary to readjust the convergence and color purity as in the conventional adjustment method, and the position of the configuration screen in the vertical direction can be adjusted independently. Yes, you can easily adjust the vertical position of the composition screen.

[0012]

[Effect of device]

 As described above, according to the present invention, while adjusting the vertical deflection yoke, it is not necessary to adjust the screen position in the vertical direction of the screen in consideration of convergence and purity. There is an effect that the position can be easily adjusted continuously by the DC bias adjusting means.

[Brief description of drawings]

FIG. 1 is a circuit block diagram showing a configuration of a vertical deflection circuit of a CRT according to an embodiment of the present invention.

FIG. 2 is a circuit block diagram showing a configuration of a vertical deflection circuit of a conventional CRT.

[Explanation of symbols]

 5 Vertical deflection coil 11 Variable resistor 14 DC bias circuit (DC bias adjusting means)

Claims (2)

[Scope of utility model registration request] 1. In a vertical deflection circuit of a CRT for applying a sawtooth deflection current to the vertical deflection coil to deflect the screen vertically, a direct current for adjusting the screen position in the vertical direction of the screen is provided on the feedback side of the vertical deflection coil. A vertical deflection circuit of a CRT, characterized in that a bias adjusting means is provided. 2. The CRT vertical deflection circuit according to claim 1, wherein the DC bias adjusting means is a DC bias circuit that superimposes a feedback voltage on a feedback side through a variable resistor, and adjusts the screen position in the vertical direction. A vertical deflection circuit for a CRT, which can be continuously performed.