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MEXICOWANDERER's avatar
MEXICOWANDERER
Explorer
Jul 29, 2014

555 Timer RC Calculations For Strobe

This is for an extreme high intensity LED strobe intrusion deterrent. Extreme strobe disorients burglars even when they have flashlights.

Calculator broke and cannot seem to access online RC sites.

555 will feed an opto coupler

Astable

150 ms pulse

250 ms interval

12 volt motion detector activated (feed to 555 timer)

need capacitor and resistor sizes.

Celso is headed north and fetching all the ingredients for all my ongoing projects.

Strobe is to thwart night time petty thief outdoor kitchen area.

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  • SCVJeff's avatar
    SCVJeff
    Explorer
    Jul 29, 2014
    If I can find my TTL Cookbook, it has an RC graph. I built many many projects with these in their time and they were lots of fun. If you are firing a real strobe, be aware that the discharge will play havoc with any receiver in the area.
  • GordonThree's avatar
    GordonThree
    Explorer
    Jul 29, 2014
    100k, 200k, 1uf cap yields 221 ms / 152 ms according to

    http://web.udl.es/usuaris/p7806757/555-calculadora/555%20Calculator.htm

    never messed much with 555, I just program 6/8 pin micro to blink however I need :)

    edit!

    I think I misread your post.

    133k, 100k, 1uf yields 161ms HIGH, 70ms LOW, 231ms TOTAL

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