KR0143136B1 - Method and device for automatically tuning in av device - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic tuning method and apparatus for automatically executing broadcast search in a television receiver, an audio apparatus, or the like.

In general automatic tuning, when the tuning voltage VT applied to the tuner 2 is changed and the automatic tuning voltage AFT for the tuner 2 becomes a constant value, the tuning state after a predetermined time thereafter is based on the tuning state. It is supposed to execute broadcast search.

Therefore, in the conventional automatic tuning, there has been a problem that some broadcasts cannot be searched according to the characteristics of the tuner and the cable band of the signal.

In the present invention, after the automatic fine voltage (AFT) has reached a predetermined level, the time when the broadcast search is executed is set according to the level of the automatic fine voltage (AFT). Thus, in the present invention, the tuning operation is performed. As it is executed, the tuning precision is improved, enabling precise tuning.

Description

Automatic tuning method of AV device and device

1 is a block diagram showing an autotuning apparatus of a general AV apparatus.

FIG. 2 is a waveform diagram for explaining the operation of the apparatus shown in FIG.

3 is a functional block diagram showing an automatic tuning device of an AV device according to an embodiment of the present invention.

4 is a flowchart of the operation of the apparatus shown in FIG.

* Explanation of symbols for main parts of the drawings

1: antenna 2: tuner

3: IF circuit 4: Image processing unit

5: Remote control device 6: Receiver

9: A / D converter 10: PWM circuit

11: Integrator 12: Channel Memo

13: Timer 30: microprocessor

31: comparison unit 32: coefficient determination unit

33: level determining unit 34: program memory

35: data memory 36: control unit

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tuning system for broadcasting station in a television receiver (hereinafter referred to as TV) or an audio device, and more particularly, to an automatic tuning method for an AV device that automatically searches for a broadcast signal and sets a plurality of broadcast channels. Relates to a device.

Recently, in the home AV (Aoudio Video) device such as TV audio, car car audio, etc., when the user selects the auto-tuning function, the device itself searches for the broadcasting frequency according to each broadcasting station. By storing in memory corresponding to the preset channel selection buttons of CHn, the user can tune into each channel broadcast simply by selecting the channel selection buttons, CH1, CH2, ......... CHn. An automatic tuning function is adopted to enable this.

FIG. 1 is a block diagram showing an automatic tuning apparatus for a TV which is most widely used and used as an AV device.

In Fig. 1, reference numeral 1 denotes an antenna, 2 denotes a tuner for executing a predetermined broadcast station according to a tuning voltage VT and an automatic tone voltage AFT, and 3 denotes a tuner tuned from the broadcast frequency tuned by this tuner 2. An IF circuit for detecting a broadcast signal, 4 processes an image signal applied from the IF circuit 3, and outputs R (Red), G (Green), and B (Blue) signals accordingly. The image processing unit outputs a synchronization signal (ID) and an automatic frequency control signal (AFC).

Further, reference numeral 5 is a remote control device as selection means for selecting an automatic tuning function, 6 is a receiving unit for receiving a selection signal from this remote control device 5, 7 is an automatic tuning selection signal via this receiving unit 6; Is inputted, the microprocessor for performing automatic tuning control, which will be described in detail later, 8 is a first memory in which an operation program and various control data of the microprocessor 7 are stored.

In addition, reference numeral 9 is an A / D converter for converting an automatic frequency control signal (AFC) output from the image processor 4 into digital data, and 10 is a pulse in accordance with a control signal from the microprocessor 7. PWM circuit for generating a width modulation signal (PWM signal), 11 is an integration circuit for generating a tuning voltage (VT) for controlling the tuner 2 by integrating the PWM signal from the PWM circuit 10, 12 is A second memory, such as an EEPROM, for storing tuning data retrieved by the microprocessor 7, 13 is a timer for providing time data necessary for tuning control of the controller 7. FIG.

Next, the operation of the automatic tuning device having the above-described configuration will be described with reference to the waveform diagram shown in FIG. In addition, in FIG. 2, (a) shows a period during which a synchronization signal is detected and output from the image processing unit 4, and (b) shows a waveform showing an automatic frequency control signal (AFC) output from the image processing unit 4. It is also.

When the viewer selects the automatic tuning function using the remote control device 5, the microprocessor 7 controls the PWM circuit 10 to increase the tuning voltage VT of the tuner 2 from the image processing unit 4; It is checked whether a synchronization signal is output. In this case, the increase in the tuning voltage VT is greatly increased in consideration of the tuning speed.

Subsequently, when the synchronization signal is applied from the image processor 4 while the tuning voltage VT is increased, the microprocessor 7 lowers the increase in the tuning voltage VT through the PWM circuit 10 than before. After setting the level, the level of the automatic frequency control signal AFC applied through the A / D converter 9 is checked.

Meanwhile, when the image signal is input from the IF circuit 3, the image processor 4 outputs an automatic frequency control signal AFC for automatic fine tuning of the tuner 2, and this AFC signal is tuned to the corresponding frequency. The closer to, the lower the level, for example, from 5V to 0V.

Accordingly, as described above, the microprocessor 7 checks the level of the AFC signal, and when the level reaches an ideal value, the control data for the tuning voltage VT, that is, the PWM circuit 10, and the corresponding value are matched. The channel number may be stored in the second memory 12.

However, here, the change of the period during which the noise signal is input again through the level of the AFC signal from 5V to 0V is made very quickly.

Therefore, in the related art, when the AFC signal becomes 4.5V, for example, in FIG. 2, the microprocessor 7 controls the PWM circuit 10 to further lower the increase in the tuning voltage VT, and then the timer 13 After a certain period of time, the level of the AFC signal applied from the A / D converter 7 is inspected. If the level is 3 V or less, it is determined that tuning is performed, and the tuning voltage VT and the channel number at that time are stored in the second memory. It is supposed to be stored at (12).

After storing the tuning data for CH1 in the second memory 12 in this manner, CH1 is sequentially controlled in accordance with the above-described method of controlling the PWM PWM circuit 10 to greatly increase the tuning voltage VT. , CH2, ......... Performs autotuning for CHn.

However, the above-described conventional autotuning apparatus has the following problems.

In general, the signal gradient of the AFC signal output from the image processor 4, that is, the signal slope reduced from 5V to 0V varies for each tuner 2 or cable band of the signal. The control data stored in the first memory 8, in particular, after the AFC signal becomes 4.5V, is fixedly determined according to the time data for checking the level of the AFC signal again.

Therefore, if the level of the AFC signal is checked again after a certain time after the AFC signal reaches 4.5V, if the level is 3V or more, the corresponding broadcast channel is not taken and skipped. There is an irrationality that viewers cannot watch the broadcast because it cannot be captured even if tuning is performed.

Accordingly, an object of the present invention is to provide an automatic tuning method for an AV device and a device thereof, which are created in view of the above circumstances and are capable of precisely performing an automatic tuning operation.

An automatic tuning method of an AV device according to the present invention for achieving the above object comprises a synchronization signal detecting step of detecting a synchronization signal while increasing the tuning voltage to a first level, and increasing the tuning voltage to a second level. A level detecting step of detecting whether an automatic fine voltage applied to a tuner has reached a predetermined level, and determining whether to tune based on the level of the automatic fine voltage (AFT) after a predetermined reference time has passed after the execution of the level detecting step. And a reference time changing step of changing and setting the reference time in accordance with the tuning determination step and the level of the automatic tone voltage in this tuning determination step.

In addition, the automatic tuning device of the A / V device according to the present invention for realizing the above object is a tuner for executing a broadcast station based on the tuning voltage and the automatic tone voltage, and the synchronization signal based on the detection signal tuned by the tuner And an audio processing device for outputting an automatic tone voltage, the AV device comprising: a level detecting means for detecting a level of said automatic fine voltage, and a synchronization signal from said signal processing means and a detection level by said level detecting means; Tuning voltage varying means for varying the tuning voltage, elapsed time determining means for determining whether a predetermined reference time has elapsed after the first level is detected by the level detecting means, and after elapsed time by the elapsed time determining means; Tuning judging means for judging whether or not to tune on the basis of the level of the automatic fine voltage detected by the level detecting means; Tuning data storage means for storing tuning data corresponding to a broadcast channel tuned according to a predetermined result; and the elapsed time according to the level of the automatic tone voltage detected by the level detecting means after a time elapsed by the elapsed time determining means. And a reference time changing means for changing the reference time value of the determining means.

According to the present invention having the above-described configuration, since the tuning determination time is changed in accordance with the level of the automatic tone voltage, precise automatic tuning can be executed.

Hereinafter, an embodiment according to the present invention will be described with reference to the drawings.

3 is a functional block diagram showing an automatic tuning apparatus when the present invention is applied to a TV as one embodiment of the present invention.

Reference numeral 30 in FIG. 2 is a microprocessor, which has a number of functional configurations.

In FIG. 3, reference numeral 31 denotes a comparator for determining whether the AFC signal applied through the A / D converter 9 is, for example, 4.5V, and reference numeral 32 denotes a timer and a reference data from the controller 35, which will be described later. 13 is a counting value judging unit which compares the counting data by 13) and outputs a judging signal when the counting value of 13 is reached to the reference value. A level judgment unit for determining the level of the AFC signal applied by the converter 9 and applying it to the control unit 35, 34 is set in the coefficient value determination unit 32 according to the level determined by the level determination unit 33. 35 is a program memory in which reference data are stored, a data memory in which reference data set in the count value determining unit 32 is stored, and 36 is an automatic tuning control according to an auto tuning selection signal applied through the receiving unit 6. It is a control unit.

In addition, since other components are substantially the same as those shown in FIG. 1, detailed description thereof will be omitted.

Next, the operation of the apparatus having the above-described configuration will be described using the flowchart shown in FIG.

When the viewer selects the autotuning function using the remote controller 5 (step ST1, the control unit 36 controls the PWM circuit 10 to increase the tuning voltage VT to a large first level). ST2 step).

At this time, the control unit 36 reads the reference data cont stored in the data memory 35 and stores 3 as the default value in the data memory 35 when the reference data is zero.

Subsequently, the controller 36 determines that the synchronization signal ID is input from the image processor 4 (step ST3), and when the synchronization signal is input, increases the tuning voltage VT from the first level. It sets to a small 2nd level (ST5 step).

After that, when a determination signal indicating that the AFC signal is 4.5V is input from the comparing unit 31 (step ST5), the control unit 36 also adjusts the increase level of the tuning voltage VT to a third level smaller than the second level. And the reference data cont stored in the data memory 35 are set in the count value determining unit 32 and the timer 13 is triggered to count a predetermined time.

On the other hand, the count value determination unit 32 compares the count data applied from the timer 13 with a reference actuator cont set by the control unit 36, and when the count value reaches the reference value, determines the determination signal level. If the AFC signal at the time when the determination signal is applied from the coefficient value determination unit 32 is 1.5 V or less (step ST7), the level determination unit 33 applies a tuning voltage corresponding to the found broadcast channel. VT) and the corresponding channel number, for example, Ch1, are stored in the channel memory 12 (step ST18), and when the level of the AFC signal is greater than 1.5 V, the data is set in the coefficient determination unit 32 corresponding to the level. The reference data cont of the memory 32 is changed (ST8 to ST17 steps).

When the input of the synchronization signal ID is completed, the process returns to the step ST2 to search for the next channel.

That is, in the above embodiment, the AFC signal output from the image processor 4 becomes 4.5V, for example, and then the reference time for tuning confirmation is changed according to the level after a predetermined time has elapsed.

Therefore, when the auto tuning is performed, the tuning precision is gradually improved as the auto tuning progresses. Thus, once the auto tuning function is executed once and the auto tuning function is executed again, all channels can be searched with high precision.

In addition, this invention is not limited to the said Example, It can variously deform and implement within the range which does not deviate from the technical summary of this invention.

As described above, according to the present invention, it is possible to realize the automatic tuning method of the AV device and the device, which enable the automatic tuning operation to be executed precisely.

Claims (2)

A synchronization signal detecting step of detecting the synchronization signal ID while increasing the tuning voltage VT to the magnitude of the first level, and automatically applied to the tuner 2 while increasing the tuning voltage VT to the magnitude of the second level. A tuning detection step of determining whether or not tuning is performed based on the level of the automatic tuning voltage (AFT) after a predetermined reference time after the execution of the level detecting step. And a reference time changing step of changing and setting the reference time according to the level of the automatic fine voltage (AFT) in the tuning determination step. A tuner 2 that executes a broadcast station based on the tuning voltage VT and an automatic tone voltage AFT, and a synchronization signal ID and an automatic tone voltage based on a detection signal tuned by the tuner 2. An AV device having a signal processing means (4) for outputting an AFT, comprising: level detecting means for detecting a level of the automatic tone voltage (AFT), a synchronization signal from the signal processing means (4), and the level detection Tuning voltage varying means for varying the tuning voltage VT in accordance with the detection level by means; elapsed time determining means for determining whether a predetermined reference time has elapsed after the first level is detected by the level detecting means, and Tuning determination means for determining whether or not to tune on the basis of the level of automatic fine voltage detected by the level detection means after elapsed time by the elapsed time determination means, and corresponding to the broadcast channel tuned according to the determination result by the tuning determination means. doing Tuning data storage means for storing tuning data and a reference time for changing the reference time value of the elapsed time determining means in accordance with the level of the automatic tone voltage detected by the level detecting means after the elapsed time by the elapsed time determining means. An automatic tuning apparatus for an AV apparatus, characterized in that it comprises a changing means.