JPS58105674A - Pattern displaying device of tv set - Google Patents

Abstract

PURPOSE:To prevent occurrence of a case where the pattern displaying location on the picture is changed or disappears, by installing a means which controls the frequency of the vertical pulse signal. CONSTITUTION:When a video signal exists, a defeat signal (c) is not inputted into a signal switching means 1 and a vertical synchronizing signal (a) is impressed upon a pattern setting means 2, and then, the said means 2 uses the signal (a) as a reset signal. When no video signal exists and the defeat signal (c) is inputted, the switching means 1 impresses a vertical pulse (b) upon the pattern setting means 2 as a reset signal through a frequency controlling means 3 having two frequency controlling means. The frequency controlling means 3 is composed of two sets of frequency controlling circuits. One of the circuits is controlled to prevent the flow of images in the vertical direction when a video signal exists, and the other is controlled to set the pattern displaying location on the picture. The pattern setting means 2 counts horizontal pulses (d) and sets the pattern displaying location in the vertical direction.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pattern display device for a television receiver, for example, for displaying patterns such as time and channel number on the screen of a projection layer television receiver.

Conventionally, this type of pattern display position has a signal switching means (1) and a pattern setting means (2), as shown in FIG. signal a and a vertical oscillation circuit (
(not shown) are input, these are selectively output by a defeat signal generated when no video signal is input, and the pattern setting means (2) is reset by this output signal. At the same time, when the horizontal pulse signal d is counted, the pattern display position in the vertical direction on the screen is set.

That is, when there is a video signal, the defeat signal C
is not input to the signal switching means (1), but the vertical synchronizing signal a is input to the pattern setting means (ri) and used as a reset signal.On the other hand, when there is no Eirin signal, the defeat signal C is input. , a vertical pulse signal is input to the pattern setting means (g), and is used as a reset signal.

By the way, the frequency of the vertical pulse signal is set using the vertical synchronization adjustment knob (V-HOL) so that the video does not flow in the vertical direction.
It is adjusted as appropriate by changing the resistance value of the variable resistor linked to D).

Therefore, when the video signal is no longer input and the vertical pulse signal is used as a reset signal to the pattern setting means, the frequency of the vertical pulse signal is equal to the above V.
-Since it is adjusted by HOI and D, the vertical synchronization signal a
deviates from the frequency of

However, due to this shifted frequency, the pattern setting means (rounding) is reset, the pattern display position in the vertical direction of the screen moves, and sometimes the pattern disappears from the screen.

The present invention was made in order to eliminate the above-mentioned conventional drawbacks, and provides a pattern display device for a television receiver in which the pattern display position on the screen does not change or disappear depending on the presence or absence of a video signal. The purpose is to

explain.

In Figure 3, (3) is a frequency adjustment means provided before the signal switching means (1), and this frequency adjustment means (3) is used to adjust the first and second frequencies as shown in Figure 3. It has adjustment circuits (4) and (E), and these circuits (4) and (E) are selectively activated depending on whether or not the defeat signal C is input to adjust the frequency of the vertical pulse signal S. It is something that can be adjusted.

The frequency adjustment circuit (2) of the above fs1 is a transistor (
(To), (B) and bias resistance (B), (To), (
b) and the main V for adjusting the frequency of the vertical pulse signal.
- It consists of a variable resistor (2) linked to the HOLD knob, and the second frequency adjustment circuit (to) is connected to a transistor,
Bias resistance (total) and variable resistance linked to sub-V-HOLD knob for frequency adjustment of vertical pulse signal 0
It consists of Zeng.

When the defeat signal C is input to the terminal (b) of the frequency adjusting means (8), the transistors (2) and (b) become conductive and the transistor (6) becomes non-conductive, so that the signal is transmitted to the resistor ( Since it flows through the transistor, the frequency of the vertical pulse signal is adjusted by the variable resistor linked to the sub-V-HOLD trench.

On the other hand, when the defeat signal C is not input to the terminal (c), the signal flows through the resistor (2) and the transistor αυ, so the frequency of the vertical pulse signal is determined by the main-V-HOLD knob, as in the past. Linked variable resistance (
2).

Therefore, when the video signal is input, that is, when the defeat signal C is not input, the vertical synchronization signal 1 is output from the signal switching means (1), and this resets the pattern setting means (2). At this time, the frequency of the vertical pulse signal can be appropriately set by the first frequency adjustment circuit (36) in order to prevent the vertical flow of the image line, as in the conventional case.

On the other hand, when the video signal is not input and the defeat signal C is input, the vertical pulse signal S is output from the signal switching means (1). Adjusted by the adjustment circuit (2). Therefore, the sub-V-H is adjusted so that the pattern display position on the screen is the same as the color when the above video signal is input.
All you have to do is turn the OLD to set the resistance value of the variable resistor α-.If you do this, even if the first frequency adjustment circuit (to) changes the frequency of the vertical pulse signal so that the pattern disappears from the screen. Even if the vertical pulse signal is set in a range that It will never go away.

As explained above, according to the present invention, the pattern display position on the screen changes depending on the presence or absence of a video signal, and the pattern does not disappear.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a pattern display device of a conventional television receiver, FIG. 2 is a block diagram showing a pattern display device of a television receiver according to an embodiment of the present invention, and FIG. FIG. 2 is a circuit diagram showing the main parts of. (1)...signal switching means, (ri...pattern setting means, (1)...frequency adjustment means, (to), (2)...
- jll and 20th frequency adjustment circuit, 1... Vertical synchronizing signal, b... Vertical pulse signal, d... Horizontal pulse signal. Note that the same reference numerals in the figures indicate the same or corresponding parts. Agent Shin Kuzuno (1 other person)

Claims (1)

[Claims] (1) signal switching means for selectively outputting a vertical synchronization signal of a television signal and a vertical pulse signal from a vertical oscillation circuit depending on the presence or absence of a defeat signal; and pattern setting means for setting the pattern display position in the vertical direction on the screen by counting the horizontal pulse signals of the television signal; A pattern display device for a television receiver, comprising: frequency adjustment means having first and second frequency adjustment circuits for adjusting the frequency of the television receiver.