Can a light dimmer be activated by noise: Advice for novice

Discussion in 'The Projects Forum' started by mondo_johns, May 13, 2011.

  1. mondo_johns

    Thread Starter New Member

    May 13, 2011
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    I was wondering if anyone out there could help with this.

    What I'd like to do is to have a set-up that automatically dims the lights in a room when it picks up noise in said room. ie. there's a direct correlation between light and noise: the louder it gets, the darker it gets.

    As I said I'm a complete novice to this kind of stuff and would much appreciate any help and advice with this project.

    Thanks
     
  2. Bernard

    AAC Fanatic!

    Aug 7, 2008
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    Yes. If you use a " Dawn to Dusk " light control yhen you can supply the controlling light with a LED shining into its window. Use Bill Marsden's flickering LED circuit to control the LED; uses music as input, noise should work. How long should dimming last after noise stops?
     
  3. ErnieM

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    Apr 24, 2011
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    CLAP ON {clap} {clap}

    CLAP OFF {clap} {clap}

    CLAP ON CLAP OFF

    THE CLAPPER!

    {clap} {clap}
     
  4. someonesdad

    Senior Member

    Jul 7, 2009
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    That's a new one -- an AAC post gives a man the clap...
     
  5. mondo_johns

    Thread Starter New Member

    May 13, 2011
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    thanks for your replies.

    Bernard, there should be an almost direct correlation. so if the noise slowly petered out then the light would slowly get brighter again. or if there was a sudden change in volume they would flick back up quickly(you get the idea)

    where can i find out about Marsden's flickering LED circuit??

    thanks again
    (i'll use protection next time)
     
  6. Bernard

    AAC Fanatic!

    Aug 7, 2008
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    I looked up Bill's blog & found his index. Chapter 12, flickering LED's , figure 12.4, example A & B.
     
  7. Bernard

    AAC Fanatic!

    Aug 7, 2008
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    A slightly simpler way: I connected a Radio Shack electret condenser mike, 270-092A, to a RS Mini Amplifier-Speaker, 277-1008C, & from the external output jack connected two diodes, a 1.2k resistor & a red LED. Dropping a quarter an a hard floor, killed a 100W bulb[ turned it off].May want to add some filtering to output for longer delay. The amplifier is still stocked by RS.
     
  8. mondo_johns

    Thread Starter New Member

    May 13, 2011
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    thanks for this. do you have a link to the correct blog page?
     
  9. Wendy

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    Mar 24, 2008
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  10. Bernard

    AAC Fanatic!

    Aug 7, 2008
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    Another version: Breadborded & tested using one TL 082 OP AMP, with an 8 V battery supply, 4, AA Ni-Cd & 2 AAA alk. Parts were those within arms reach, but generally in right range. I wanted a 100 K pot, but the 30 K already had leads. One OP AMP was a little low on gain, so used second OP AMP as gain of 100 +_, LED responds to breathing, or rattling keys in pocket. Suggested power supply - a 9 V AC/DC adapter.The Dimmer from ACE Hardware, has a plug in light shield, which makes mounting LED easy with cork washer. Woops- lost C5, 220 uF, + to junction D2 & R7; - to gronnd. If a longer than 2 sec. delay is desired, then add transistor as emitter follower [ MPSA 14 etc ].
     
    Last edited: May 21, 2011
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