Blinking 5mm LEDs DIY Kit, FREE SHIPPING

  • $8.25

Product Description

This electronic kit uses two light emitting diodes(LEDs) to alternately blink by using a flip flop circuit. Two transistors are used to alternately turn on and off.

If Q1 turns on first, the voltage on the VCE(Q1) will be closed to 0V and caused D1 LED to turn on. This caused Q2 to be in the OFF state as the base voltage of Q2 is not forward bias. D2 will be in OFF state.

Capacitor C1 will be charged up(opposite to its polarity) through R2 resistor and when it reaches 0.7V, transistor Q2 will turn ON causing D2 LED to turn ON. This will cause the negative terminal of C2 to drop in voltage and transistor Q1 will turn off causing D1 LED to turn OFF.

This process repeats itself and the timing of the flashing depends on the values of R2, R3, C1 and C2. Try changing the values and you will get different results.

The electronic parts come in loose form and will have to be soldered to the printed circuit board that comes with this kit. Basic soldering and electronic knowledge are necessary to assemble this kit. 


Parts & Specs

  • Supply Voltage: 3V to 9V DC
  • One Printed Circuit Board
  • Two 5mm light emitting diodes
  • Two NPN transistors
  • Two 47uF electrolytic capacitors
  • Two 10KΩ resistors
  • Two 470Ω resistors
  • Wires for DC supply connection

Packing Details 

  • Item:  Blinking LEDs DIY Kit
  • Package Size: 10cm X 10cm X 10cm (3.94in X 3.94in X 3.94in)
  • Package Weight: 0.03kg (0.07lb)


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