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Author Topic: 555 Breathing (Pulsing) LED  (Read 9754 times)

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  • Cadet
  • Posts: 1
555 Breathing (Pulsing) LED
« on: February 14, 2016, 14:13:11 PM »

I am new to this forum and new to electronics.

I am currently trying to build the 555 Breathing (Pulsing) LED and the most I can get is the LED comes on and then goes off and that is it.. I see looking at the photo of the breadboard there are 2 resistors that seem to nowhere, 1 off pin3 and 2 toward the bottom right corner? The only other change on mine is the 2N2222, I am using a 2N2222A. Also have slightly different potentiometer but they are 10K. Can someone please help?



  • Cadet
  • Posts: 1
Re: 555 Breathing (Pulsing) LED
« Reply #1 on: October 12, 2017, 15:30:11 PM »
Good Morning all,

I have exactly the same problem. It lights up once, and then stays off all the time.
I checked the voltage in the capacitor, and it's changing due to 555, but led does not light up.

I also tried to connect directly the led with a resistor to pin 3, and it blinks well.

Video here: https://youtu.be/XInVuIA9g8c

Any idea?

« Last Edit: October 12, 2017, 15:48:13 PM by urameshix »