One feature that I’ve wanted to build for a model railroad is a theater or cinema with a lighted marquee outlined in chase lights. Specifically, the “moving hole” type of chase lights, where only one channel is off at a time, while the others normally remain lit, making it appear that groups of lights are chasing with small gaps between them, as opposed to several single lights chasing with big gaps between them. A four-channel circuit might be sufficient, but it would be worth experimenting with up to ten channels.
The first circuit I’ll test for this type of marquee is found in Figure 10 on this post at Nuts & Volts. My intention is to use this circuit to illuminate a series of four to ten LEDs somewhere behind the scenes. The marquee would be outfitted with fiber optic strands inserted into drilled holes from behind, outlining the sign. In a four-channel marquee, for example, every fourth fiber optic strand would be attached to one of the four LEDs, creating the same chase effect as shown in the animation above, while using just four LEDs instead of one for each point of light on the sign.
The other thing I really want to incorporate into a cinema marquee is the ability to change the text on the sign, for different movies or plays. That will certainly take some experimentation to get right.
UPDATE: Here’s another “moving hole” variation, where the illuminated segment is still three lights, but the dark segment is six lights.
