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MTH F-3 B-Unit Operating Manual
QUICK START - BASIC OPERATION
The MTH F-3 B Unit contains state-of-the art electronics with several
built-in automatic features for incredibly realistic operation. The F-3
B-Unit is easy to operate with your existing MTH F-3 AA or ABA units
using any compatible standard AC transformer (see the compatibility chart
on page 8). The F-3 powered B-Unit is controlled by a DCRU® electronic
reverse unit which 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). Simply plug the B-Unit wire harness into the
existing sockets of the F-3 AA or ABA set to allow Proto-Coupler®
equipped engines and directional lighting systems to function. Once
connected, advance the transformer throttle to cycle all AA and B units
together from RESET to Forward as explained in the DCRU section below.
DCRU® REVERSE UNIT
As mentioned in the Basic Operating section, the engine is controlled by a
DCRU® reverse unit that contains the standard forward-neutral-reverse
states found on most reverse units. However, when power is first applied to
the track, the reverse unit begins in RESET or what seems like a neutral
state. Power must be interrupted again to get the locomotive to enter the
forward state. The system will enter RESET whenever power to the track is
off for three or more seconds. NEUTRAL should be referred to as the state
between Forward and Reverse.
Because the ProtoSound® system or DCRU® reverse unit found in your
powered MTH F-3 A unit is not directly connected to the DCRU® unit in
your powered F-3 B-Unit, you
must cycle the power on and off
slowly to maintain proper
synchronization between each
powered unit’s reverse unit. If
the units should become
unsynchronized, simply shut
down power for three or more
seconds. Upon repowering, each
unit should come up in RESET. If you choose to operate your existing F-3
A units in a “locked-out” state, a lockout switch on the powered F-3 B-Unit
has been provided so that you can manually “lock-out” the B-Unit in the
same direction the powered A Units are configured.
RESET
Neutral
Reverse
Neutral
Forward
Figure 2: DCRU™ Cycle Phases
