How to make a Drawer Alarm, which sounds when a dark draw is opened.
As shown to the right, by simply adding a battery holder, switch and buzzer to a PCB built in the ‘light activated’ configuration you can create an alarm that sounds when a dark draw is opened and the PCB is exposed to light. The switch is to allow the alarm to be activated or deactivated.
Parts List:
- Light activated switch (stock code 2112)
- 2 x AA Battery cage with lead (stock code 2232-25 – pack of 25)
- Miniature DPDT slide switch (stock code 3404 – pack of 10)
- Piezo buzzers (stock code 3301-pack of 10)
- Zinc Chloride AA batteries (2201-50 – box of 40)
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