I know just enough to be dangerous, when I was actually working in electronics we still used bulbs for lighting
We need to know what to use with an AC or DC circuit, wallwarts or regular train power supplies, or batteries.
We need to know how to wire for a single LED or multiple LEDs for passenger cars and buildings (single story and multi-story), single/dual headlights in conventional and command control engines, even vehicles.
We need to know how to use the LEDs from Christmas trees, probably the cheapest source for LEDs anywhere and readily available.
The one thing I always think of when talking LEDs is that there seems to be no standard approach (schematic) when using them because of the infinite number of possibilities due to the way properties change depending on the number of LEDs used. I know there must be standards, it just hasn't registered in the old noggin yet.
