Alarm Project Kit

The kit can be used to make a shed or room alarm. It is armed / disarmed by a hidden switch. Alarms are detected by a micro switch mounted onto a door. A timer provides an entry delay during which the system can be disarmed, whilst a separate timer silences the alarm after two minutes. Both of these timers are implemented via a 555 timer IC.

The alarm can be further enhanced by using a simple key switch for arming / disarming or by adding a magnetic door contact to activate it. The board, battery pack & buzzer can be placed into a box designed by the student.

Kit contents:

• 1 x PP3 Clip Lead
• 1 x 4AA Battery Holder
• 1 x Slide Switch
• 1 x 556 (dual 555) Timer IC
• 1 x 14 pin IC Holder
• 1 x Piezo Buzzer
• 4 x 10nF Ceramic Capacitors
• 2 x 100uF Electrolytic Capacitors
• 1 x 330ohm Resistor
• 3 x 10Kohm Resistors
• 1 x 220Kohm Resistor
• 2 x 1.2Mohm Resistors
• 1 x Micro Switch
• 1 x 5mm Red LED
• 0.5m connecting Wire
• 1 x Alarm PCB
• Supplied in Tough Plastic box with internal dimensions of 95 x 60 x 35mm

PCB dimensions: 51mm x 41.5mm.

Requires  4 x AA batteries, available separately.

Click here to download instructions.