USP

USP (for interruptible signal processing) is a Lenz brand name for a very straightforward idea: an RC circuit to power a locomotive during very brief outages of power. DCC is particularly prone to stopping on points as a brief interruption to the power causes the controller to reboot; however careful you are with your points this does seem to be a perennial problem. The USP prevents this and keeps the model running. It is perfect for models with few pickups, especially shunting engines which spend half their lives running over the most neglected bits of track on your railway.