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How to Make a 12 Volt LED Flash/Strobe

A strobe, also called a strobe light or stroboscope, provides light that flashes on and off at regular intervals. It is used as a siren in police vehicles or fire trucks. It is also used in toys, as a warning indicator for alarm systems, or to supply different lighting effects in discos. Strobes commonly use xenon flash tubes as a light source, but some use LEDs instead. This is because LEDs are inexpensive, durable, and come in several different colors. To make a 12-volt LED flash/strobe, use a 555 timer chip. The maximum flash rate is set with a capacitor and resistor combination.

Things You'll Need

555 timer chip
LED
50uF capacitor
560-ohm resistor
1k-ohm resistor
12V power supply
Breadboard
Jumper wires

Instructions

- 1
  Select a row or column on the breadboard as the voltage source, and choose a row of as ground. Insert the 555 timer chip into the breadboard. Its notch should point left, and each of its pins falls must be placed in separate columns.
- 2
  Insert a jumper wire between pins 2 and 6 so that they are connected. Attach pin 4 to the voltage source with a jumper wire. Connect pin 8 to the voltage source also, and use a jumper wire to connect pin 1 to ground.
- 3
  Insert the 50uF capacitor so that its negative lead is at ground, and its positive lead is at pin 2. Connect the middle or wiper lead of the potentiometer to pin 7, and one of its ends to pin 8.
- 4
  Connect the 1k resistor so that one of its leads is at pin 2, and its other lead is at pin 7. Attach the LED's negative lead to pin 3, and its positive lead to one end of a 560 resistor. Use to a jumper wire to connect the resistor's other end to the voltage source.
- 5
  Place the power supply on a 12-volt setting. Connect its red lead to the voltage source row or column on the breadboard, and its black lead to ground.
- 6
  Switch the power on so that the LED will begin flashing. Turn the potentiometer knob to adjust the flash rate.

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