MTH Protosound (Proto 1) & Postwar ZW Transformer Horn Activation Questions

The speed change was actually designed into Lionel transformers of that era.  It was necessary in order to compensate for a steam locomotive's motor slowing down as the electromechanical whistle motor in its tender spins up.  This happens because the whistle motor is generally a current hog, especially when compared to the electronic whistles of today.

Although it may not be readily apparent the whistle button on your ZW has three positions as a result, and not just two.  The three, as I understand it, are the following:

1. Off -- The standard position without your finger on the button
2. Start -- Pushed down about 1/2 way; activates the whistle function
3. Boost -- Pushed down all the way; adds voltage to the track to compensate for locomotive slowdown

You might want to try pushing the button down only 1/2 way and see if that helps.

Mike

Thanks. It helps at cruising speeds for sure.

I'm thinking seriously about adding some Adafruit boards to my layout for different sounds and that would give me more options with equipment without sound as well as background noises from things like a highway.