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Railway Crossing Lights psd

a pair of alternating, blinking LEDs

Recent activity:

  • psd updated12 years ago
  • psd board processed12 years ago
  • psd schematic processed12 years ago
  • psd board received12 years ago
  • psd schematic received12 years ago
  • psd pushed to12 years ago

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A tweak of the blinking LED, a 555 Timer circuit to alternate between a pair of LEDs, a bit like a railway crossing signal.




Bill of Materials

Designator Value Description
C1 10µF Electrolytic capacitor; 1µF; voltage 10V
R1 1kΩ Resistor
R2 470kΩ Resistor
R3, R4 470Ω Resistor
LED1, LED2 LED-05R 5mm LED red
U1 NE555 555 Timer
VCC1 9V 9V battery, PP3 or similar



This project is published under the terms of the BSD License licence.