Here's my solution for passenger car and caboose lighting on an HO scale DCC layout:
There are no apparent "in-rush" current problems.
Brightness might be too bright, requiring a higher rated resistor (dependent on strip LED).
Flicker free operation is perfect, as in, there is no flicker!
If you're interested in the details, photos and the wiring schematic, let me know.
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Subject: [w4dccqa] Updated album Car lighting keep alive cap #photo-notice
Don Weigt <dweigt47@...> updated the album Car lighting keep alive cap: Greg Harter's passenger car lighting board with added capacitor. Greg reports lighting is constant for more than five seconds after power is removed from the rails. One photo is of the car with DCC power on the rails, the other after about five seconds without power. Can you tell which is which? The lighting board is from Walthers. The wires to the capacitor can be thin, as typically used wiring decoders. lt is possible long passenger trains with multiple cars would cause a problem by briefly drawing too much current when power is applied. If that happened, one fix would be to put a ten to about twenty Ohm resistor in either capacitor lead. This would reduce "keep alive" time a bit, as well as add complexity. The total modification cost per car would still be under half a dollar if the parts were bought from most online sources.