Timed Burglar Alarm N/O - N/C

Posted on Feb 4, 2014

This is a simple but effective alarm circuit which can reset its self after a time that you select. it has normally open and normally closed triggers which make this circuit very practical. This alarm has normally open and normally closed triggers. It`s on a 555 timer so the alarm will reset it`s self after a certain amount of time. The time is ad

Timed Burglar Alarm N/O - N/C
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justable with the variable resistor in the circuit. The alarm has a reset switch which you can replace with a key switch to make it more secure, and you can change the triggers to other types of door or window switched too. The alarmuses a relay which is connected to a siren but you can replace the siren with whatever you want. The circuit is running off 9VOLTS but can range from 4V - 16V. Disclaimer: All the information present on this site are for personal use only. No commercial use is permitted without the prior permission from authors of this website. All content on this site is provided as is and without any guarantee on any kind, implied or otherwise. We cannot be held responsible for any errors, omissions, or damages arising out of use of information available on this web site. The content in this site may contain COPYRIGHTED information and should not be reproduced in any way without prior permission from the authors.

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