Easy

Vibration/Tilt Sensor Alarm

A small vibration (or tilt) sensor closes a contact when moved or tilted — combined with a buzzer, it becomes a simple anti-tamper alarm for a box or drawer.

Circuit Diagram

+9V Vibration/tilt sensor pull-down R (base → GND) Q BC547 C → buzzer E → GND BUZZER Sensor still → Q stays off, silent. Shake/tilt → contact closes → buzzer sounds

How to Build It

  1. Connect the vibration/tilt sensor between the positive rail and a BC547 transistor's base, with a pull-down resistor to GND on the base.
  2. Connect the transistor's collector to a buzzer and then to the positive rail.
  3. Connect the emitter to GND.
  4. Power the circuit — the buzzer should stay silent with the sensor still.
  5. Gently shake the sensor or tilt the board — the buzzer should sound.

Bill of Materials

ProductCodeQty
Buzzer LD-BZPG-2312 1
Resistor DR47K-8/9 1
Sensor / sensor module OKY3438 1
Transistor (incl. IGBT) — 1
← All kits  ·  Newsletter