4-6-4 J3a Hudson Steam Locomotive
15
M.T.H. engines equipped with Proto-Sound 2.0 are equipped with Proto-Speed Control
which allows the locomotive to maintain a constant speed up and down grades and
around curves, much like an automobile cruise control. You can add or drop cars on the
run, and the engine will maintain the speed you set.
While the engine is programmed to start with the speed control feature activated, you can
opt to turn it off. This means the engine's speed will fall as it labors up a hill and increase
as it travels downward. It is also affected by the addition or releasing of cars while on the
run. Because the engine will run more slowly at a given throttle voltage when speed
control is on than when it is off, you should adjust the throttle to a lower power level for
operation with speed control off to avoid high-speed derailments. When speed control is
off, the sound volume will drop to allow for better low voltage operation.
To turn speed control on and off
Place the locomotive in neutral, then quickly tap the transformer's Horn button one time
then quickly tap the Bell button two times, allowing approximately ½ second to lapse
between each quick button press. Two horn blasts will indicate that the engine has made
the change. Repeat the 1 horn, 2 bells code to return it to the other condition. You will
want to do this during the initial neutral upon start-up if you ever couple this engine to
another engine that is not equipped with speed control to avoid damaging the motors in
either engine. Each time you shut down the engine completely, it will automatically turn
speed control on.
Horn
Place
Engine into
Neutral
Bell
Bell
=
Speed Control
Two Horn Blasts
Repeat to Return
to Normal Condition
( indicates change is made)
Speed Control
