(original version 10-29-2013)
Clay Cowgill, October 29th, 2013
The graphic at the top of the screen is the marquee design I did in Photoshop. We've been building our own LED marquee backlights for Ground Kontrol for a number of years now, so this was just an extension on that technique. I took RGB LED strips and some cool white strips and mounted them to foamcore board for backing. The CPU Brain Parasite directly controls the LED strings with the current sinks and PWM.
I did a test illumination of the marquee with red LEDs only and noticed that the blue background almost totally disappeared. That turned in to the basis for a neat lighting effect you can see in the video on the main page-- by placing the red LEDs in the center of the array and the white abd blue around the edges, by turning the blue lights on only the blue tones in the marquee are visible. When the red comes on, the blue doesn't change brightness very much at all, so it looks like just the red lettering is somehow lighting up. Pretty neat looking.