Led flasher

Posted on Dec 4, 2012

A relaxation oscillator is used to flash an LED in the base circuit. Cl is charged slowly through R1 by the power source, then discharged periodically through R3 and the LED by the UJT.

Click here to download the full size of the above Circuit.

Flashing rate is determined by the supply voltage and by Rl-Cl's time constant. UJT = 2N4871

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