| 摘 要： | Test card for color TV is a widely used method to evaluate the quality of a TV set directly.We havemade a test signal generator(which can also generate synchronizing(abbreviated to sync hereafter)signals)mainly based on microprocessor Z-80.Taking the advantage of microprocessor programming,combiningwith the technique of microprocessor,digital circuits and analogue devices,we use software as far as possibleto generate signals directly or to simplify the controlling circuits.Those signals,such as composite syncsignal,blanking signal and a series of test signals are originally realized by a number of sequential circuitsand logical gates.Now,this test signal generator has smaller size,higher stability and lower cost comparedwith former ones which consist of more hardware.All of the programs are stored in EPROM.We can changethe test patterns and their orders easily by changing the programs without changing the main structure of thesystem.On the other hand,varied kinds of non-standard TV sync signals and test patterns can also beobtained in this way.
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