KR19980066510A - Tuner Intermediate Frequency Gain Checking Device and Method - Google Patents

Abstract

An apparatus and method for checking an intermediate frequency gain of a tuner are disclosed. The apparatus includes channel control means for selecting a desired VHF channel and outputting a control signal corresponding to the selected channel, power supply means for supplying power to the channel control means and the tuner, and a predetermined frequency band corresponding to the control signal. A signal generating means for outputting a signal to a tuner, converting an intermediate frequency signal input from the tuner, and outputting it as a vertical signal, a horizontal signal, or a marker signal, and processing and processing the input vertical signal, a horizontal signal, and a marker signal. And an analog / digital converting means for inputting the output of the preprocessing means and converting it into a digital signal, and a control means for inputting the output of the analog / digital converting means and checking the gain. It has the effect of improving the reliability, improving the quality and suitable for mass production system.

Description

Tuner Intermediate Frequency Gain Checking Device and Method

TECHNICAL FIELD The present invention relates to a tuner, and more particularly, to a tuner gain checking apparatus and method for automatically checking an intermediate frequency (IF) gain of a tuner.

Hereinafter, with reference to the accompanying drawings, the configuration and operation of a conventional tuner gain test apparatus will be described as follows.

1 is a block diagram of a conventional tuner gain test apparatus, which includes a channel control unit 10 for selecting a desired VHF channel, a power supply unit 12 for supplying power to the channel control unit 10 and the tuner 14, and a gain test. A tuner 14 generating an intermediate frequency, a swimmer for outputting a signal of a constant frequency band and supplying a signal to the oscilloscope 18 so that the intermediate frequency gain can be checked by inputting an intermediate frequency signal from the tuner 14. It consists of an oscilloscope 18 which inputs a signal from the generator 16 and the swimmer generator 18 and displays it to the operator.

First, the operator seats the tuner 14 to check the intermediate frequency gain in a fixed jig, and then controls the power supply unit 12 to supply power to the channel control unit 10 and the tuner 12. After the power is supplied, the channel preset in the swimmer generator 16 is selected using the channel controller 10. The tuner 14 inputs a signal of a corresponding channel from the swimmer generator 16, tunes the input signal into an intermediate frequency signal, and outputs the converted intermediate frequency signal to the swimmer generator 16. The swarm generator 16 converts an intermediate frequency signal input from the tuner 14 into a signal that can be seen by the oscilloscope 18 and outputs it to the oscilloscope 18. Finally, the operator visually checks through the oscilloscope 18 whether the gain of the intermediate frequency signal is correct.

The above-described conventional tuner inspection apparatus visually inspects the gain of the tuner through an oscilloscope, so that when the inspection is performed for a long time in mass production, the accuracy of the operator decreases and the reliability of the inspection decreases, thus producing high quality products. There is a difficult problem.

SUMMARY OF THE INVENTION The present invention has been made in an effort to provide an apparatus for checking a tuner's intermediate frequency gain, which can automatically inspect the tuner's intermediate frequency gain.

Another object of the present invention is to provide a method for checking an intermediate frequency gain of a tuner performed by the apparatus for checking an intermediate frequency gain of the tuner.

1 is a block diagram of a conventional tuner gain test apparatus.

2 is a block diagram of an apparatus for checking an intermediate frequency gain of a tuner according to the present invention.

3 (a), (b) and (c) are waveform diagrams of vertical signals, horizontal signals, and marker signals.

4 is a graph showing PIF gain and GIF gain.

5 is a flowchart illustrating a method for checking an intermediate frequency gain of a tuner according to the present invention.

In order to achieve the above object, the tuner intermediate frequency gain inspection apparatus according to the present invention for checking the intermediate frequency gain of the tuner, the channel control means for selecting a desired VHF channel, and outputs a control signal corresponding to the selected channel, and A channel control means and a power supply means for supplying power to the tuner, and output a signal having a predetermined frequency band to the tuner in accordance with the control signal, and convert an intermediate frequency signal input from the tuner to convert a vertical signal and a horizontal signal. Signal generation means for outputting as a marker signal, preprocessing means for signal processing, processing and outputting the input vertical signal, the horizontal signal and the marker signal, and converting the output of the preprocessing means into a digital signal Inputting the analog / digital conversion means and the output of the analog / digital conversion means to obtain the gain. It is preferably configured as a control means for use.

In accordance with another aspect of the present invention, there is provided a method for checking an intermediate frequency gain of a tuner according to the present invention, including a signal processing and processing step of processing and processing a vertical signal, a horizontal signal, and a marker signal; A signal conversion step of converting the marker signal into a digital signal, a number setting step of setting a number of times of inspection, a first determination step of continuously determining whether a peak value of the vertical signal is greater than or equal to a predetermined threshold value, and the vertical A first data storing step of storing times at which the value of the marker signal rises abruptly and values of the vertical signal at the times when the peak value of the signal is greater than or equal to the predetermined threshold value; and the peak value of the vertical signal; A second data storage step of storing the data; a second determination step of determining whether all the data have been stored by the number of times; If the data has been stored, the step of checking the intermediate frequency gain using the stored data and if not all the data has been stored the number of times, continuously determining whether the value of the vertical signal is the predetermined threshold, and If the value of the vertical signal is the predetermined threshold, it is preferable that the third determination step proceeds to the first determination step.

Hereinafter, with reference to the accompanying drawings, the configuration and operation of the tuner intermediate frequency gain tester according to the present invention will be described as follows.

2 is a block diagram of an apparatus for checking an intermediate frequency gain of a tuner according to the present invention, which includes a channel control unit 20, a tuner 22 to be inspected, a power supply unit 24, a signal generator 26, and a preprocessor 30. And an analog-to-digital converter (ADC) 44 and a controller 46.

The preprocessor 30 shown in FIG. 2 is composed of first, second and third filters 32, 34 and 36, a peak detector 40, a derivative and signal checker 38 and a buffer 42.

3A, 3B, and 3C are waveform diagrams of vertical signals, horizontal signals, and marker signals input from the signal generator 26 shown in FIG. 2 to the preprocessor 30.

The channel control unit 20, the tuner 22, the power supply unit 24, and the signal generation unit 26 illustrated in FIG. 2 are the channel control unit 10, the tuner 14, and the power supply unit 12 illustrated in FIG. 1. And corresponding to the swarm generator 16, and performs the same function, the description of the operation is omitted here.

Meanwhile, the first, second, and third filters 32, 34, and 36 respectively input the vertical signal, the horizontal signal, and the marker signal shown in FIGS. 3A, 3B, and 3C to remove noise. It performs the function. The vertical, horizontal and marker signals that the signal generator 26 inputs the intermediate frequency signal from the tuner 22 and outputs to the respective filters have periodicity. The waveform shown in FIG. Corresponds to the waveform of.

4 is a graph showing a PIF gain and a GIF gain, reference numeral 60 denotes a portion generated by a vertical signal and a horizontal signal, and 62 and 64 denote markers generated by a marker signal.

The derivative and signal checking unit 38 inputs the horizontal signal from which the noise is removed from the second filter 34 to differentiate, and determines whether the differentiated value is positive, and if it is positive, the peak signal detecting unit 40. ) And to the buffer 42. This is because in order to detect the gain of the intermediate frequency signal, values of other signals are needed only while the horizontal signal is inclined positive.

The vertical signal shown in FIG. 2A output from the first filter 32 and the marker signal output from the third filter 36 are respectively input to the buffer 42 and buffered. On the other hand, the peak detector 40 is provided separately to reduce the burden of the inspection software, detects the peak value of the noise-free vertical signal in response to the enable signal, and outputs the detected peak value to the buffer 42. Here, the buffer 42 outputs the buffered signals and peak values to the ADC 44 in response to the enable signal.

When the enable signal is positive, the ADC 44 inputs a vertical signal, a marker signal, and a peak value from the buffer 42 to recognize a digital signal that can be recognized by the controller 46 which can be implemented by a personal computer (not shown). The digital signal is converted to the control unit 46 and output to the converted digital signal. The control section 46 inputs the digital vertical and marker signals and the peak value to determine whether the gain is good or not, and stores the production management data.

Hereinafter, a method for checking an intermediate frequency gain of a tuner according to the present invention will be described with reference to the accompanying drawings.

FIG. 5 is a flowchart illustrating a method for checking an intermediate frequency gain of a tuner according to the present invention, comprising: determining whether an enable signal is input (steps 80 to 84), and storing data necessary for inspection a predetermined number of times; Step (steps 86 to 92) and performing the inspection using the stored data (step 94).

First, the preprocessor 30 of the apparatus shown in FIG. 2 preprocesses the vertical, horizontal and marker signals, and the preprocessed analog signals are converted into digital signals (step 90). In step 80, if the slope of the horizontal signal is not positive, the value of 0 is continuously converted to digital. After step 80, the number of times of gain checking is set (step 82). This is because the vertical, horizontal, and marker signals input have periodicity. Therefore, if the inspection is performed only once, the accuracy is deteriorated. Therefore, the inspection is performed by using the extracted data several times.

After step 92, it is determined whether the peak value of the vertical signal is equal to or greater than '0' (step 84). Here, the peak value of 0 or more means that the enable signal has been output, that is, the slope of the horizontal signal is positive. In this case, a valid signal is input from the ADC 44 to the controller 46.

When the peak value is '0' or more, it detects when the value of the digital marker output from the ADC 44 suddenly rises, and the time at the first rise and the time at the second rise and the vertical signal at those times. Save the values of (step 86). These stored values are essential data for the examination of the intermediate frequency gain.

After step 96, that is, after the second rise is completed, the peak value of the vertical signal is stored (step 88). After the 88th step, the data storage of one cycle is finished, and it is determined whether the data has been stored the number of times set in the 82nd step (step 90). If data has been stored as many times, the intermediate frequency gain is checked using the stored data (step 94). However, if the data has not been stored the number of times, in order to store the data again, it is determined whether the value of the vertical signal is '0' (step 92). If the value of the vertical signal becomes '0', that is, if the buffer 42 is disabled, the flow proceeds to step 84 and the operations from step 84 to step 88 are repeated.

As described above, the tuner's intermediate frequency gain tester and method according to the present invention automatically checks the tuner's gain through a computer, thereby increasing the reliability of the test, improving the quality, and being suitable for mass production systems. There is.

Claims (3)

In the tuner intermediate frequency gain tester for checking the tuner intermediate frequency gain, Channel control means for selecting a desired VHF channel and outputting a control signal corresponding to the selected channel; Power supply means for supplying power to the channel control means and the tuner; Signal generating means for outputting a signal of a predetermined frequency band to the tuner in accordance with the control signal, converting an intermediate frequency signal input from the tuner, and outputting the signal as a vertical signal, a horizontal signal, or a marker signal; Preprocessing means for signal processing, processing and outputting the input vertical signal, the horizontal signal and the marker signal; Analog / digital conversion means for inputting the output of said preprocessing means and converting it into a digital signal; And And a control means for checking the gain by inputting the output of the analog / digital conversion means. The method of claim 1 wherein the pretreatment means First, second and third filters which respectively input the vertical signal, the horizontal signal and the marker signal from the signal generating means to remove noise; Differential and signal checking means for inputting and differentiating the horizontal signal from which the noise is removed from the second filter, and checking whether the differentiated result has a positive value; Peak detection means for detecting a peak value of the vertical signal from which the noise is removed from the first filter in response to the checked result; And And a buffer for buffering the signal and the peak value input from the first and third filters, and outputting the buffered signal and value to the analog / digital converting means in response to the checked result. Tuner medium frequency gain check device. In the tuner intermediate frequency gain test method, A signal processing and processing step of processing and processing the vertical signal, the horizontal signal and the marker signal; A signal conversion step of converting the processed vertical signal, the horizontal signal, and the marker signal into a digital signal; A number setting step of setting a number of times to be examined; A first judging step of continuously determining whether the peak value of the vertical signal is equal to or greater than a predetermined threshold value; A first data storing step of storing times at which the value of the marker signal suddenly rises and values of the vertical signal at the times when the peak value of the vertical signal is greater than or equal to the predetermined threshold value; A second data storing step of storing a peak value of the vertical signal; A second judging step for judging whether all the data have been stored the number of times; A checking step of checking the intermediate frequency gain using the stored data if all the data has been stored the number of times; And If all the data have not been stored the number of times, continuously determining whether the value of the vertical signal is the predetermined threshold, and if the value of the vertical signal is the predetermined threshold, proceeding to the first determination step And determining the intermediate frequency gain of the tuner.