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DIY – Lazer Alarm Electricity Kit – Tested & Verified (Educational projects and learning DIY kit)

DIY – Lazer Alarm Electricity Kit – Tested & Verified (Educational projects and learning DIY kit)

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ComponentSpecification
Detection TypeOptical (Light Beam Interruption)
Light SourceRed Laser Diode / High-Intensity LED
Sensor TypeLDR (Light Dependent Resistor)
Alert TypeHigh-Pitch Buzzer
Power Source9V Hi-Watt Battery (Included with Connector)
Working Distance1 - 2 Meters (Alignment Dependent)
Price
₹ 165.25 ₹ 165.25
(Tax included)

Product Description The DIY Laser Alarm Entry Alert System is a "tested and verified" security project that demonstrates the real-world application of optical sensors. By aligning a light beam with a sensitive LDR sensor, students create an invisible "tripwire." When an object or person crosses the beam, the circuit is broken, immediately triggering a loud buzzer. This kit is a favorite for science fairs and home security experiments, teaching the basics of light physics and transistor switching.

Key Features

  • Invisible Tripwire Logic: Replicates the technology used in professional museum and home security systems.

  • Precision Detection: Uses an LDR sensor that responds instantly to changes in light intensity.

  • Plug-and-Play Wiring: Features simplified color-coded connections (Blue to Blue, Red to Red, Black to Black) to ensure error-free assembly.

  • Modular Setup: The transmitter and receiver can be placed at varying distances to test the effective range of the light beam.

  • STEM Educational Focus: Provides a clear, hands-on demonstration of how light can be used as a digital input for electronic circuits.

Technical Details

  • Circuit Action: Under normal conditions, the light beam hits the LDR, keeping its resistance low and the buzzer off. When blocked, the LDR's resistance spikes, allowing the circuit to activate the alarm.

  • Alignment Troughs: Includes vertical stands to help maintain a steady line of sight between the light source and the sensor.

  • Portability: Battery-powered (9V) for use in any location without needing an AC outlet.

Prototyping and Engineering Tips from Robogears

  • The Alignment Challenge: The most critical step is perfect alignment. If the alarm stays on even when nothing is crossing the beam, use a small tube or "hood" around the LDR to prevent room lights from interfering with the sensor.

  • Range Extension: To increase the distance between the transmitter and receiver, ensure the light source is perfectly focused. You can use a small lens to concentrate the beam over longer distances.

  • Battery Efficiency: Always disconnect the battery snapper when the project is not in use. Even when the alarm is silent, the light source and sensor circuit continue to draw current.

  • Multi-Point Security: Advanced builders can use small mirrors at 45° angles to bounce the light beam around a room, creating a perimeter alarm with just one kit.

Package Includes

  • 1 x Light Source Module (Laser/LED)

  • 1 x LDR Sensor Module

  • 1 x High-Pitch Buzzer

  • 1 x Pre-Assembled Logic Board

  • 1 x 9V Hi-Watt Battery & Snapper

  • 1 x Set of Support Stands & Base

  • 1 x Complete Wiring Set

Disclaimer Images are for reference; actual wire colors or PCB layout may vary. EYE SAFETY: If the kit uses a laser diode, DO NOT look directly into the beam or point it at people or animals. Adult supervision is recommended during the initial alignment phase.