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Using a PIR to turn on a sound module Answered

Hi All,
I have used PIR sensors before but i usually hack one from a cupboard light you can buy.  What I want to do is use a really small (and cheap) board like the trinket (adafruit) and hook it up to the PIR in order to turn on a sound module.  

Does anyone know what board would be best to do this?  All the board will have to do is activate the PIR sensor.  maybe I don't need an actual whole board to get this done?  any clues would be much appreciated.

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user
FarmerKJS (author)2014-04-02

i dont have chematic software so here is the best i can do...

conect the PIR to power and ground then conect the output of the PIR to the play button of a radio shack sound recorder

http://www.radioshack.com/product/index.jsp?produc...

http://www.radioshack.com/product/index.jsp?produc...

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lonesoulsurfer (author)FarmerKJS2014-04-02

Hey there,
I've tried that before on a project and the PIR sensor only throws out 2-3 volts when activated. I need the sensor to activate the battery's which will be 4.5v

Cheers

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user

A lot depends on the sound card you want to drive.

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user

The sound card is one you can use in birthday cards. It's really about the sound card though as I want the to use it as a switch to complete the circuit for the power (4.5v)

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user

Have you tried wiring the sound module as a load on the PIR ? How do you wire them ?

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user

Not as yet. Still waiting for the sound cards to arrive!

This is how I would be wiring them up:

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user

So instead of the LED I would use the sound card. I don't believe that this will work as the PIR doesn't release enough power. so even if I used 4 aa batteries (6v) it has a voltage regulator and only releases 3V

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user

In that case, just use a transistor. Put the +ve for the sound card to the battery plus (+ve), put the -ve to the Collector of an NPN transistor, put the base to the PIR, via a 220 Ohm resistor, and put the emitter to the battery (-ve)

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user

sorry - should have read "its NOT really about the sound card though"

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FarmerKJS (author)lonesoulsurfer2014-04-03

well you could use a relay and do that

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lonesoulsurfer (author)FarmerKJS2014-04-03

Yep tried that as well. I found that the PIR didn't open the relay when it was activated. Maybe the relay I was using operated on a too high a voltage (or I could have wired it up wrong!) might give it another try.

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user

Your PIR probably can't drive a big load like a relay either.

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lonesoulsurfer (author)2014-04-03

Hi All,

I found this on eBay and will give it a try. The relay runs on 3.3v so it should be fine

http://www.ebay.com.au/itm/New-1-Channel-H-L-Level...

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