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Need assistance building sound controlled LEDS

  1. Feb 12, 2012 #1
    I am building a moving target system for a shooting range. It will have a 40 foot target moving perpendicular to the shooter. I have not had any problem with fabricating the target system, but I want to go above what the customer requires. Hopefully this lead to more work for myself in the future. From 1000 yards it can be difficult to see a 1" mark while the target is moving at 15 MPH without great optics. I am wanting to add an audio controlled (ring from when a bullet impacts steel) lighting system. I have search online stores gone into electronics shops and not many people have been helpful. So I figured an EE or EE student would be my best choice. I have come to the conclusion that a portable system would be best as it could be moved from one target to the next without laying wiring to the range. Any help on leads or help designing a circuit would be greatly appreciated. I am an automotive technician so the fabrication has been no problem, but building an LED circuit actuated by audio fools me. Thank you for your guys time.
     
  2. jcsd
  3. Feb 12, 2012 #2

    NascentOxygen

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    So this uses real bullets? You want to light up a LED sign that says, "Bulls eye" or something?

    If the slug is off-target, what sound will the microphone pick up? Will the microphone pick up background shots from other people in adjacent areas of the range?

    Not that I'll be able to help you, but the more information you can give others, the better. Have you looked at the "Similar Threads" candidates at the foot of this page?
     
    Last edited: Feb 13, 2012
  4. Feb 12, 2012 #3

    jim hardy

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    a search on "sound actuated switch kit" returned lots of hits. pick a hobby site.

    I've used Ramsey, All Electronics, PartsExpress, MPJA.

    discovercircuits dot com forums is a friendly DIY electronics site.

    I'd go with a kit - saves a lot of pain.
     
  5. Feb 13, 2012 #4
    yeah it will be a real bullet. Also there wont be any background noise. This target is going to be placed 600 to 1400 yards beyond all other targets, and if the person is off target the spotter will not see it light up. Thank you for your guys guidance on finding a kit/other sources.
     
  6. Feb 13, 2012 #5
    What high of lumens do you guys think would be necessary to see this light up from say a maximum 1760 yards (1mile) away?
     
  7. Feb 13, 2012 #6

    NascentOxygen

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    Something like a bicycle LED lamp? Maybe a pair to make it appear wider?
     
  8. Feb 14, 2012 #7
    how do you suggest that I keep it lit for say 5 seconds if I use a bike LED setup?
     
  9. Feb 15, 2012 #8

    NascentOxygen

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    An electronic timer using an IC should be straightforward. But first you need to select the sound-activated switch. Choose one or two and post a link here.

    If you know someone with a bike head lamp that uses LEDs get him/her to ride off 1 mile and then ride towards you so you can gauge its effectiveness in daylight. Maybe a LED torch (flashlight) might do the job? Some have an assembly with half a dozen LEDs.
     
  10. Feb 16, 2012 #9
    Last edited by a moderator: May 5, 2017
  11. Feb 19, 2012 #10

    NascentOxygen

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    The orvac board seems like it may do exactly what you want, as is. They don't say what the amperes capacity of the relay is, but I reckon it should be able to switch the current of a bike headlamp or similar on and off. They also don't indicate what voltage the board needs.

    The second one seems like it may need an additional small circuit to stretch the on time of your lamp to a few seconds (though we can't be sure, as the description is a little sketchy). But at 3A the relay is good enough to switch a bright LED lamp. It would probably be best to go for a lamp that runs off 12v since that is the voltage for that board, and this would save you having to construct a separate dc supply for the LEDs. 12 volts rules out using pushbike lamps, unless you could find 6v lamps and run 2 in series off 12 volts? A car headlamp or LED tail-lamp might be overkill, and probably draws way too much current, but might be worth looking into, just the same. Expensive, so price one from a junk yard. At least you'd know they'd be well sealed against the weather.

    It may be possible to make an argument for not using the mechanical relay at all, but to build an electronic circuit to do the switching for greater reliability. But this decision can be deferred until you have got the basic circuit working and adjusted.

    What sort of sound will the microphone hear? A short whistle, followed by an almighty crash?
     
    Last edited: Feb 19, 2012
  12. Feb 20, 2012 #11
    Honestly there will not be very much sound at a mile. Ballistically an average round is 900FPS give or take, some big magnum cartridges upwards of 1800 FPS. So, it will be a "TING" Sound is right around the 5 minute mark
     
    Last edited by a moderator: Sep 25, 2014
  13. Feb 23, 2012 #12
    would one of these be able to power a relay?
     
  14. Feb 25, 2012 #13

    NascentOxygen

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    They both have a relay on the board.
     
  15. Feb 26, 2012 #14
    Sorry should have clarified. I meant to power a standard automotive relay to power 10 amps switched. I have found on a sunny day a bike style led system is not bright enough. 2 projector fog lights are just right.
     
  16. Feb 26, 2012 #15

    NascentOxygen

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    You should be able to use the on-board relay to operate the car relay, but you'll have to look at the specs of the car relay. I'm wondering whether red lights might stand out better than white lights? You'd have them mounted against something matt black.
     
  17. Feb 27, 2012 #16
    I have bright white in an orange housing.
     
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