John,
I do not run DCS at the present time only Legacy/TMCC. I am curious though about needing the choke for DCS, what does this do? I ask because I can not say I will never have DCS especially if MTH decides to make locomotives in road names I desire to have. Why is the choke needed for DCS and not the Lionel system? I am not an electronics expert but have done these strip LEDs in most of my coaches.
Ray
The 12V LED strips actually start to light around 8 volts, there are three LEDs in series with the resistor.
You would want the LM317T for the lights if you want to vary the intensity. You can use it in either a variable voltage mode or a variable current mode. I like the variable current mode, that's what I use for my lighting modules. Here's a diagram of what's in my lighting module, you can wire this from components if you choose. If you KNOW you'll never run DCS, you can omit the choke. This circuit gives you about 5ma to 45ma of current. I find at 45MA of current, the LED strips in an 18" passenger car are way too bright for my tastes, so this works out pretty well.
