Step 6: Reassembly

To run the extra signal and ground wire, I cut a small square notch from the lip of the base plastic piece and secured it with hot melt glue, after zip-tying the two wires together.  Hot glue was reapplied to secure the battery clip.

And that's it!  You now have a battery powered smoke sensor for your next home automation, science project, or DIY security system!
<p>This is fun but you should have a proper smoke alarm for your house. And you should check it regularly </p><p><a href="http://www.gregsmithelectricianbendigo.com/bendigo-electrical-contractor/smoke-alarm-battery/" rel="nofollow">http://www.gregsmithelectricianbendigo.com/bendigo-electrical-contractor/smoke-alarm-battery/</a></p>
<p>I suppose you can make this detector become like a switch, to turn on something while it is detecting smoke. I'd like to make it turn on a fan while there is smoke in the room.</p>
redxine hello, I'm still green in the RPI. Could you please send me the scripts and instructions on how to get into the lives of the smoke sensor BL59S10. <br> <br>Thank you.
Hi! Interesting article. There is a similar article at <a href="http://complexit.se/publications/Network.based.smoke.alarm-using.Arduino.and.iPhone.pdf" rel="nofollow">http://complexit.se/publications/Network.based.smoke.alarm-using.Arduino.and.iPhone.pdf</a>&nbsp;that might be of interest.
Great work! <br> <br>What do you think about using the wiring to the piezo speaker as the I/O to a microcontroller? <br> <br>Thanks! <br>Owen
Update: The datasheet says there's a sawtooth output on pin 12 of the chip. The output rating for the piezo is 16mA, 6.5V, with a period of 9.5 ms makes the frequency ~105 Hz, so a proper filter capacitor would be: <br> <br>C = I/(2F*V). <br>C = 0.016 mA / (2 * 105Hz * 0.5V) <br>C = 0.0152 Farads <br> <br>double check my maths though.
I haven't tested it yet, however since the pezio has to be driven that means the alarm output on the detector is putting out a 20-ish KHz sine wave, so it should just be a matter of wiring in a capacitor or diode to rectify the signal. I'd check the output on a meter or scope if possible before piping it into a micro though. I'd do it myself but I'm travelling and my workbench is packed away. <br> <br>Cheers. <br>Zak
In am wondering if it is possible to wire a standard smoke alarm to a speaker/buzzer of a lower frequency. It is typical for people loosing their hearing to loose the high frequency first. For instance I cannot hear anything above 3000hz and very poor below that. If I could have a smoke detector below 2000hz I might hear it. As it is I can stand right under a ringing smoke alarm that is driving everyone else nuts and I don't hear it at all. The manufacturers make hearing impaired smoke detectors that are louder...blink a light or talk to you. but this is not going to wake me up if it goes at night. Can you provide any insight into this?<br>Thanks in advance.
Absolutely! It is simply a matter of modifying a detector with any of the chips listed in step 4 as per above and connecting the buzzer. However, since lower frequency buzzers will more than likely draw more than 100 mA, you may need a transistor or FET to switch the buzzer. I've attached a schematic for simple switching with a transistor or relay below. Be sure that the working voltage for the buzzer is close to 9V, otherwise an additional battery or external supply will be needed.<br> <br> I will be adding this and more to a going farther step later, in addition to what to do for detector chips without an I/O pin (as soon as I find one!). I have only tested what's here with optical detectors, as they have become much cheaper and much more common here in Europe.<br> <br> I hope this helps.<br> Edit:&nbsp; didn't realize how instructables would resize the image.&nbsp; Schematic is here:&nbsp; <a href="http://jkltech.net/screenshot49.png" rel="nofollow">http://jkltech.net/screenshot49.png</a>

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