| 摘要 |
PURPOSE: A device for controlling video signals is provided to input a horizontal scanning line number to be measured, and to generate a trigger signal to connect a video signal with the trigger signal by an oscilloscope, thereby directly specifying and measuring a scanning line to be measured. CONSTITUTION: A buffer(21) inputs composite video signals(a). A signal separator(22) receives the video signals to separate a vertical synchronous signal(b), a horizontal synchronous signal(c), and a field identifying signal(d). A counter(23) receives the vertical and the horizontal synchronous signals to generate a count value(g), and outputs the count value. An input unit(24) specifies a horizontal scanning line number to be measured, and rotatively inputs the number by using a rotary encoder. A micro computer(25) increases/decreases a horizontal line value(f) according to the horizontal scanning line number, and decides whether a signal is normally inputted or a signal kind. A display(26) displays a scanning line to be measured according to a horizontal line value. A comparator(27) compares a count signal with each binary code value of the horizontal line value. If the two signals are the same, the comparator generates an 'H' signal. If the two signals are not the same, the comparator generates an "L" signal to output a trigger signal(h).
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