you have written on site that triac is only use for DC but the triac is only use for AC and only control line. its frequency range is 0-400hz.
I suspect you misread and misquoted what was in the book. However, you are free to register and we can discuss it in the electronics chat forum. It is easy to do and free.Feedback and Suggestions Forum for providing feedback and suggestions about All About Circuits, including corrections to the e-book. This forum is not for getting help with technical questions.
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