This sketch has come in handy at least once a day since I made it.
If all you want is a 0v or just lower volt "start" you can have it, and cheaply, but you will loose an equal amount off max voltage at full throttle. Every bump across the windings remains proportional the same.
It does not effect low power tourqe patterns of a motor. That would take skillful rewinding, varying counts by a few wraps here and there & or different wire gauge. There are folks that will perform the service. OR re-gearing, a lost art more or less.
It does not affect your whistle, but could be set up as a second "no boost"(maybe a slight slowdown) light boost (maybe no change) or big boost, etc. for whistle or bell controller for use on railsounds and later as well. Remove a diode or two of a single direction from the circuit and it will become an offset voltage and trigger boards and some mechanical relays as well. One direction of diode(s) removed it is whistle, if the other it is bell.
10amp is for the LW, yours may differ if larger. If the transformer is smaller than 10a max output your fine at 10amp. 3 or 4 of these total should get you close enough to zero to have trouble with a lone low power l.e.d. You're looking at a deck of cards size on 4-6 of them. They WILL get hot if closely rated so maybe cover them, enclose them, heatsink if you want to, etc.
Some creative switch wiring or tapping could possible get some DC power . I haven't looked.
