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MTH Big Boy Operating Manual
QUICK START - BASIC OPERATION
The MTH Big Boy contains state-of-the art electronics with several
built-in automatic features for incredibly realistic operation. Despite these
advanced features, the Big Boy is easy to operate with any compatible
standard AC transformer (see the compatibility chart on page 34). All
models are equipped with an operating smoke system that
should be primed
with smoke fluid before operating
. Adding 15 - 20 drops of fluid through
the smoke stack should be sufficient.
If you choose to not prime the units
with fluid
,
turn the smoke unit switch located under the leading truck to
the OFF position
. (See Figure 1) This will prevent any damage from
occurring to the smoke unit when running the engine without a primed
smoke unit. For more information see the section on page 4 on Smoke Unit
operation.
The Big Boy model is controlled by a
ProtoSound® DCRU® electronic reverse
unit. The reverse unit operates in the same
manner that all reverse units function by
using forward, neutral and reverse states
that are entered each time the throttle is
turned on and off or by using the
transformer direction switch (if so
equipped).
The reverse unit is designed to ignore dirty track, dead spots on switches
or minor short circuits without
disrupting the engine operation,
even at slow, prototypical speeds.
Before the engine can be operated
however, the reverse unit plug that
extends out of the tender must be
inserted into the receptacle at the back of the boiler cab as seen in Figure 1.
Once the plug is inserted, the throttle on the transformer can be advanced.
You will see that only the engine’s lights come on and that on ProtoSound
equipped engines, two dings from the sound system will chime followed by
the steam compressor pump sounds. The engine does not run. This is
known as the RESET state and is explained in more detail beginning on
Page 6. The ProtoSound® DCRU® will not power the motor until the
throttle is turned OFF and then ON again. At this point, the engine will
now function just like any other electronic or mechanical E-unit.
Use first hole for O-72 operation.
Use 2nd hole for display and 96 inch
or larger diameter curves.
Plug Tender Plug into
Boiler Socket at back of cab.
Figure 1: Plugging in the tender harness
RESET
Neutral
Reverse
Neutral
Forward
Figure 2: ProtoSound® DCRU® Cycle Phases
