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Tech Forum

March 2018

Chasing Lights

I’m trying to emulate the chasing lights that used to be popular under the awnings at the cinema. I have a chasing LED circuit that works well, but I want to turn the LEDs off slowly to leave the comet trail effect. I’ve tried putting a 2,200µF cap in parallel with each LED with limited success.

There must be a simple way to have the LEDs turn on quickly and then fade out.

Trevor Watson
via Internet