R van Heerden

Discussion in 'General Electronics Chat' started by rvh002@gmail.com, Sep 17, 2010.

  1. rvh002@gmail.com

    Thread Starter Active Member

    May 15, 2009
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    Hi, I am looking to design/manufacture a couple (3) flashlight circuits. The supply is 12V DC and the trigger will be a movement sensor. It will be an outdoor circiut so a fair amount of power must be used by the 'flash"
    Any ideas ?
     
  2. retched

    AAC Fanatic!

    Dec 5, 2009
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    By "flash" do you mean camera strobe?

    Or do you want a motion detector that will light a path when triggered?
     
  3. Kermit2

    AAC Fanatic!

    Feb 5, 2010
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    Garage door automation uses IR beams to detect people and cars...

    Cameras have flash circuits that charge quickly and are triggered by a switch, which can be changed for a relay...

    Lots of possibilities if you want to get creative with already made "off the shelf" components. Just put together an idea and source the parts and you have a new product that requires no special manufacturing or design. Everything is already existing and in stock somewhere, being used in other products.
     
  4. rvh002@gmail.com

    Thread Starter Active Member

    May 15, 2009
    118
    2
    Thanks for the ideas. I am planning to use external sensors to trigger a flash. The idea is to use high intensity LED's. Either two or four white ones. The LED's must be driven by a mosfet or similar. The mosfet to be triggered by a schmit trigger or similar and it in turn must be triggered by the external sensors. The whole lot to be powered from a 12volt battery.






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  5. Kermit2

    AAC Fanatic!

    Feb 5, 2010
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    Are they going to look at a perimeter, like crossing a line to trigger,or is it a wide area field you want to detect movement in?
     
  6. rvh002@gmail.com

    Thread Starter Active Member

    May 15, 2009
    118
    2
    The sensors will be looking up and down a street from a pole mounted box about 3meters up from ground level. I have suitable outdoor sensors that have relay contact open or closed outputs. These (I presume) open contact upon closing must fire a mosfet/fet to momentarily turn the high power white led's on to act like a flash. A bright flash is all I need as the whole setup is really a scare tactic for unwanted individuals in a very remote residential area. No actual photography wiil take place, so no need for any sincronisation.. My knowledge of high power led's are unfortunately a bit lacking. I can lay my hands on 10W led's and that is what I presume will make enough light to look like a flash. Maybe two or four of them in some configuration.










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  7. marshallf3

    Well-Known Member

    Jul 26, 2010
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    All you need for the flashes is a bag full of the flash units sold by Goldmine for anywhere from 0.99 to 0.49 when on sale. They come out of those disposable cameras and run off a single AA cell which could be kept at full charge with a solar cell.
     
  8. retched

    AAC Fanatic!

    Dec 5, 2009
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    I agree with marshallf3.

    10w LEDs are gonna cost you a bundle. You can get slave flash units from Ritz Camera for 10 bucks.

    Seal them up with some hot glue and you have an "all weather unit"
     
  9. rvh002@gmail.com

    Thread Starter Active Member

    May 15, 2009
    118
    2
    Thanks for the ideas.
     
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