I used 12-volt warm white LED strips because they were the least exspensive and most readily available at the time. That color value looked best in heavyweight coaches anyway. Amtrak coaches might look better with a cool white to represent bright fluorescent lights. The choke is an Epcos/TDK with a value of 22 millihenries that I bought from Mouser for $0.35 each. I don't see that choke on the Mouser website any longer, but there are some that are close to those in terms of price and below half an amp in maximum current.
The bridge rectifier is also from Mouser, an RB153:
https://www.mouser.com/c/?q=RB153
The capacitor is a 35-volt 1000 microfarad piece that didn't perform much better than a 470 mF capacitor. I have found that clean track and wheels make a much better contribution to reducing flickering than the capacitors have.
One source for inexpensive buck-boost converters is:
https://www.amazon.com/XL6009-...B07XG323G8&psc=1
I can't comment on their quality because I have not used them, but I suspect that if they work, it is a good idea to check their output because all the ones I tested with a voltmeter had to be turned down to 7-8 volts to prevent burning out the LED strips before use.
Terry
