How to make a circuit turn on and off really fast automatically ?

i know a switch does that but i want to make the circuit to turn on and off automatically with current in it or anything to do this

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  • 1 decade ago
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    If you have a Radio Shack locally you can make one quite easily with a few dollars worth of parts. Many timing circuits made with the "555" timing chip, available at Radio Shack, and can create timing intervals from literally hours down to mili-seconds. You can do a search on Google such as "555 timing circuit" and you will get plenty of hits. As long as you can read an electrical schematic and if you have a soldering iron you can make it. You only need a few more electrical components to create the circuit. The circuit can be battery or line powered (with a step-down transformer and rectifier (AC to DC converter)), and can switch small voltages by itself, or when connected to activate a relay can switch very large voltages/amps.

    Here are some pages:

    http://www.doctronics.co.uk/555.htm

    (the schematic for the "astable" circuit would be one you could use. Astable just means the circuit will keep switching the output on and off indefinetly. Connect the output to a relay for higher voltage/amperage switching.)

    http://www.electronics-project-design.com/LED-Flas...

    (On this page you could substitute a relay where one of the LED's would go. However since in this circuit the LED is also driven directly off the 555 chip you would need to use transistor between the 555 timer output and the relay since relay's consume more power than the 555 can safely put out).

    -Hopefully this helps you!

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  • 1 decade ago

    You would need to supply more information re what is it that you want to turn on and off, at what rate, whether it's battery or mains powered... anything that has any relevance to what you want to do, in fact. Please edit into your question, and maybe someone can help you.

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  • 1 decade ago

    maybe a relay will solve your problems with a timer/PWM circuit.

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