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How to pulse electric a current

  1. Jan 5, 2008 #1
    How to "pulse" electric a current

    I'm looking for a way, or component, that will pulse an electrical current through a circuit, and I'm not sure where to start looking. I'm looking to hook a 9v battery to a small simple circuit and send the current through that circuit in pulses. For example on-off-on-off.
  2. jcsd
  3. Jan 5, 2008 #2


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    Try looking at IC 555 timer chip circuits. What you want is an astable multivibrator.
  4. Jan 6, 2008 #3
    It would help a lot to describe the frequency of the pulse. Please be specific to get an educated guess. Don't expect an exact answer but one that will point you in the right direction.
    Last edited: Jan 6, 2008
  5. Jan 6, 2008 #4
    After reading your question closer, one thing I could do is make a multivibrator out of two nine volt DC relays. The multivibrator frequency would be determined by the RL of the relays. I have never tried this but would give a guess at 20HZ? The frequency depends on the RL circuit and the larger the relays the slower it would flip-flop. But if all you want to do is use a simple 555 timer then go for it.
    Last edited: Jan 6, 2008
  6. Jan 8, 2008 #5
    Thanks guys for the help! I'm new to this, and find it very interesting. I don't think I know enough to answer your questions with a lot of detail. What I'm imagining is a circuit similar to (but not exactly like) a string of flashing christmas tree lights. Some strings give you the ability to set their speed: slow, fast, or solid/no flash. Since I'm new to this, I'd like the ability to adjust the speed the "pulses" travel through the circuit to see how things react at different speeds: slow, medium, fast, etc. From what I've read, the 555 timer would be a good start.

    Any books or on-line articles you can suggest would be great too! Thanks again!
  7. Jan 8, 2008 #6


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