Fairy Flashing LED Lights


Posted on Feb 6, 2014

This simple and cheap circuit is not just for Christmas! There are just two resistors, a small-signal transistor such as a BC547, one flashing` LED and a string of normal` LEDs. The flashing LED works as an oscillator and switches the transistor on and off; and the transistor switches all the other LEDs. An (unregulated) 12 V mains supply can be u


Fairy Flashing LED Lights
Click here to download the full size of the above Circuit.

sed for power. No current-limiting resistor is required in the LED chain, because the forward voltages of the LEDs in the chain add up to the supply voltage. If red LEDs are used, with a voltage drop of 1. 65 V, then 12 V will supply seven; alternatively, use six yellow (2. 1 V each) or five green (2. 7 V). You can of course always mix the colours. Alongside the NPN transistor add a PNP transistor with its emitter connected to +12 V, with another string of LEDs connected down to ground. The two strings will flash alternately. Be the first of your friends to get free diy electronics projects, circuits diagrams, hacks, mods, gadgets & gizmo automatically each time we publish. Your email address & privacy are safe with us !




Leave Comment

characters left:

Related Circuits

  • New Circuits

    .

     


    Popular Circuits

    LED display Digital Calendar AT89C2051
    10 To 1Hz Timebase Circuit
    Triac circuit
    water level sensor circuit
    4 order filter with a single IC project PCB
    High Power Led Driver With Dimmer
    Exit Sign With Battery Protection
    Microphone AGC amplifier
    A-3-7-type air compressor control circuit



    Top