Hi guys, I've got a bit of a tricky problem here. (To my thin knowledge of electronics anyway!) I want to replace the bulb found in some scalextric cars with a single LED. (The bulb light goes through some perspex tubes to come out of the headlights etc) Can someone help me make something to provide a fairly constant DC voltage from the varying DC voltage that you get from the track? I measured the various outputs, and it varies from about 8V-16V fairly quickly, depending on the throttle position at the controller. Ideally I'd like something fairly simple that I can solder onto a single LED leg/small board to stick inside the car? There are some 3rd party circuits out there, but they're full-board type jobs which need fixing into the car, which I'd rather not do. Especially because they're ~£10 each. Upshot: I want a white LED to provide a near-constant brightness. Thanks in advance!