Smoke Detector Teardown

Written By: Ari Dubinsky (and one other contributor)

Published: March 4, 2014

Community-Contributed Guide

Comments: 3
Favorites: 18
Views: 8.5k

Smoke Detector Teardown

Written By: Ari Dubinsky (and one other contributor)

Published: March 4, 2014

Community-Contributed Guide

Comments: 3
Favorites: 18
Views: 8.5k

Teardown

Introduction

Go to step 1

For our reverse engineering project, we chose to use the smoke detector. This smoke detector consists of a sensor to detect smoke and a loud electronic buzzer to alert people within the building.

What you need

Parts

2.5 mm Flathead Screwdriver

Tools

This teardown is not a repair guide. To repair your Gas and Smoke Detector, use our service manual.

Step 1 Smoke Detector Teardown

Smoke Detector Teardown, Smoke Detector Teardown: step 1, image 1 of 2

Smoke Detector Teardown, Smoke Detector Teardown: step 1, image 2 of 2

Use a screwdriver to pry open the plastic enclosure. It might be easier to push the buzzer through the hole, if you need extra leverage.

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Step 2

The buzzer is unhooked from the PCB board, by hands.

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Step 3

This is the circuit for the smoke detector. It is powered by a 9V battery. The 3 metal leafs are contacts for the buzzer and the bigger leaf is for the test button.

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Step 4

The metal cap is removed to reveal a, MC145017, driver chip and americium sensor. Do not remove americium from the sensor!

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why did you do this do you know how dangerous that is americium 231 is a highly radioactive metal you could HAVE KILLED YOURSELVES

Alex Matthiessen - Oct 8, 2014 Reply

Americium 231 hasn't been confirmed. Ionization smoke alarms contain tiny amounts of americium 241, which is relatively harmless unless you ingest/inhale it, and even then it's potentially carcinogenic, but not carcinogenic enough to cause immediate ill effects.

River Saxton - May 29, 2024