Sound sensing circuit

[Ron Davis]

I am looking for a simple circuit that will toggle on a small LED flasher
when it senses a very loud noise. It will need to toggle the other circuit
on and stay on even after the noise has subsided. Maybe with a reset switch
to start the thing over again. Something similar to the "clapper" for
controlling lights but just need the on condition. Also need some
adjustment to vary the sensitivity and/or frequency that will be picked up.

This is for a daughters science fair project. Thanks.

 

[bj]

"Ron Davis" <rondavis9@comcast.net> wrote in message
news:7KudnUe_DNoZVpDdRVn-tA@comcast.com...

I am looking for a simple circuit that will toggle on a small LED flasher
when it senses a very loud noise. It will need to toggle the other
circuit
on and stay on even after the noise has subsided. Maybe with a reset
switch
to start the thing over again. Something similar to the "clapper" for
controlling lights but just need the on condition. Also need some
adjustment to vary the sensitivity and/or frequency that will be picked
up.

This is for a daughters science fair project. Thanks.

Velleman sell a "pocket sound level meter"(MK115) for about Ł6 which has 5
LEDs that light up depending on volume,

apparently you're supposed to pin this to your shirt and be the cool
dude at the disco.
I bought this thing to measure sound levels for a project I'm working
on and I reckon all I have to do is use one of
the LED outputs to do whatever I want

cheers bj

 

[Blue Lightning]

You might be able to use a one-shot LM555 timer circuit to do the
trick. Check out this web page:
http://www.talkingelectronics.com/FreeProjects/555/555-P1.html. Look
at "THE 555 AS A MONOSTABLE". If you wire the circuit this way and
make your pulse length very huge you can achieve your goal.

"Ron Davis" <rondavis9@comcast.net> wrote in message news:<7KudnUe_DNoZVpDdRVn-tA@comcast.com>...

I am looking for a simple circuit that will toggle on a small LED flasher
when it senses a very loud noise. It will need to toggle the other circuit
on and stay on even after the noise has subsided. Maybe with a reset switch
to start the thing over again. Something similar to the "clapper" for
controlling lights but just need the on condition. Also need some
adjustment to vary the sensitivity and/or frequency that will be picked up.

This is for a daughters science fair project. Thanks.