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The Security Alarm kit: a recycled enclosure with a breadboard and an empty recovered battery holder inside, an LED and a switch mounted in its wall, a cabled magnetic reed-switch contact, a recovered ring magnet and screws Magnetic detection

STEM kit · Sensors

Security Alarm

Build a simple alarm system and explore switches, LEDs and magnetic detection.

₹249 Batteries not included

About 40 g of parts recovered from discarded electronics get a second life in every kit. (Estimate)

  • A magnetic contact (reed switch) responds to a nearby magnet, the idea behind simple door and window sensors.
  • A switch and an LED to see how the circuit changes state.
  • Built on a breadboard inside a recycled enclosure.

Price excludes delivery. Ships from Ambattur, Tamil Nadu. India Post delivery (Normal or Express) is calculated at checkout from your PIN code.

Batteries are not included with ReSpark kits. New AA cells may be required for operation. Salvaged battery cells are never included.

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About this kit

See how a magnet can switch a circuit.

A reed switch is a small switch that responds to a magnetic field. Place it on one side of a door and a magnet on the other, and you have the basic idea behind many door and window sensors.

Students wire the magnetic contact, a switch and an LED on a breadboard, mount everything in a recycled enclosure, and test how moving the magnet changes the circuit.

What you’ll explore

  • Switches
  • LEDs
  • Magnetic detection
  • Reed switches
  • Breadboard circuits

What’s in the kit

Recovered where suitable. New where it matters.

ReSpark combines suitable recovered components with selected new components to create affordable, safe and reliable STEM kits.

Recovered / reused

Recovered / Reused Components

Components that can safely be recovered from suitable discarded electronics after inspection and testing.

  • LEDFrom suitable old electronics
  • Battery holderRecovered from old toys and devices, reused after appropriate quality checks. It holds new cells only.
  • WiresFrom suitable e-waste
  • EnclosureRecycled enclosure
  • MagnetMay be recovered from suitable discarded electronics
New

New Components

Components intentionally purchased new because they are inexpensive, safety-critical, difficult to recover reliably, or unsuitable for reuse.

  • Magnetic contact / reed switchTreated as a new component where required
  • SwitchTurns the alarm circuit on and off
  • Breadboard / simple circuitThe circuit students build and test
  • Screws / fastenersFor assembling the enclosure

Not included: batteries. New AA cells may be required for operation.

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