•  
  •  

Timed Burglar Alarm

Contributed by, Richard Johnson

N/O – N/C Timed Burglar Alarm

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 adjustable 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 alarm uses 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.

If there are any problems please contact webmaster@electronic-circuits-diagrams.com

Please share & like


Rechargeable Voice Amplifier Microphone Headset Speaker Teacher Meeting Speech picture

Rechargeable Voice Amplifier Microphone Headset Speaker Teacher Meeting Speech

$16.14



E1R1 FIREYE INFRARED AUTO-CHECK FLAME AMPLIFIER MODULE picture

E1R1 FIREYE INFRARED AUTO-CHECK FLAME AMPLIFIER MODULE

$395.00



SKAN-A-MATIC T31103 AMPLIFIER picture

SKAN-A-MATIC T31103 AMPLIFIER

$203.98



Phoenix Contact MCR-C-U/U-DC  Isolating Amplifier picture

Phoenix Contact MCR-C-U/U-DC Isolating Amplifier

$345.07



Personal Speaker Portable Voice Amplifier for Teachers with Microphone Headset picture

Personal Speaker Portable Voice Amplifier for Teachers with Microphone Headset

$16.99



Bud AC 1421 Aluminum Enclosure Chassis for Tube Amp 9x15x3 Amplifier picture

Bud AC 1421 Aluminum Enclosure Chassis for Tube Amp 9x15x3 Amplifier

$20.00



Voice Amp Amplifier Model 200260 Scott EPIC Safety Compatible w AV3000 AV2000 picture

Voice Amp Amplifier Model 200260 Scott EPIC Safety Compatible w AV3000 AV2000

$60.00



KYOWA WGA-710C Instrumentation Amplifier New Open Box  picture

KYOWA WGA-710C Instrumentation Amplifier New Open Box

$499.89



Fanuc A06B-6090-H003 Servo Amplifier - WARRANTY picture

Fanuc A06B-6090-H003 Servo Amplifier - WARRANTY

$399.00



MURR ELEKTRONIK 636039 AMPLIFIER CARD BASE picture

MURR ELEKTRONIK 636039 AMPLIFIER CARD BASE

$249.70