North Coast Engineering has come out with a new device.  Called the "Snubber" it is a track voltage spike suppressor: 

Use with any DCC system to prevent large voltage spikes.

Features of this product:

• Reduces or eliminates voltage spikes on long runs of DCC bus wire
• Protects decoders from damaging inductive voltage spikes
• Solve temporary loss of control or runaway problems
• Preserves DCC waveform accuracy

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