Function
Idle/Moving
F0
Headlight on/off or cycle of dim, bright, off
F1
Bell on/off
F2
Horn
F3
Mars light on/off with air release
F4
Coupling 1
F5
Brake release (idle) / brake squeal (moving)
F6
Dynamic brake on/off
F7
Air hose firing/uncoupling lever
F8
Click 3 times during idle will shut down / notch down while CV122=3
F9
Engine cooling fan / notch up while CV122=3
F10
Rail wheel clack (only moving)
F11
Traction air compressor
F12
Change prime diesel mover type, (4 types) including off
F13
Short air release
F14
Coupling 2
F15
Air pump
F16
Associated loco sound
F17
Flange noise 1
F18
Change bell type (use F1 to turn off bell after adjustment)
F19
Horn type select (total 34 different horns)
F20
Associated loco sound
F21
Change bell volume (use F1 to turn off bell after adjustment)
F22
Change horn volume
F23
Change diesel rumble volume
F24
Air release
F25
Flange noise 2
F26
Flange noise 3
F27
Sand drop
F28
Mars light flash enable/disable with Air release (CV 121)
Note- Bell, Dynamic Brake, and Rail-Wheel Clack, cannot play at the
same time.
ADDITIONAL INFORMATION
The MRC 1803 HO gauge synchronized diesel sound decoder should perform
well when used with other brand command systems. See your DCC
command stations manual to learn how to program and operate the decoder.
For more information about register/CVs and their functions, please refer to
the NMRA DCC Standard & Recommended practices, RP-9.2.2 this is available
directly from the NMRA or their website at
www.nmra.org.
INSTALLATION
Refer to the instructions that came with your PA/PB locomotive for removal
of the body shell. Remove the three screws that hold down the original
circuit board. Don’t lose these screws, you will need two of them to install
the decoder. Gently lift the original circuit board and note the locomotives
wire colors and locations from where they originate inside the chassis.
remove the plastic clips that hold these wires to the original circuit board,
and remove the wires from the circuit board. You will use the clips to
attach the wires to the decoder.
There are three red wires, (four red wires if the loco has a mars light), and
four black wires, do not mix these up! Two red wires are from the right
side wheel pickups, one red wire goes to the motor brush, and one red
wire goes to the mars light if equipped. Two black wires are from the left
side wheel pick ups, and one black wire goes to the motor brush. The
other black wire goes to the headlight. The other wires are as follows-
yellow to headlight. white and blue to the mars light, (if equipped), with the
blue wire as the mars light common. The decoder is set up to use the
bulbs that came with the locomotive, no change is needed. Install the
wires to the decoder as
noted in the following
diagram. make sure to
twist the wire leads tightly
as not to have a stray strand
cause a short circuit on the
decoder. Use the plastic
clips to attach the wires to
the decoder. You can also
solder the wires to the
decoder if you prefer instead
of using the clips.
There are three circuit board stand offs on the rear of the chassis that the
original circuit board sat on. The three screws removed earlier held the
circuit board to these stand offs. Only the two front stand offs are needed.
The stand off on the rear corner can be clipped flush with the chassis
with a pair of diagonal cutting pliers. Please wear safety glasses when
clipping the stand off. Install the decoder with wires attached onto the
front two stand offs and secure the decoder with two of the screws
removed earlier.
Note- if you do not wish to clip the stand off, place a small piece of
insulating tape over the stand off where it contacts the underside of the
decoder.
Re-install body shell making sure none of the wires that go to the
decoder are pinched or pulled out.
Make a Test Track
Before you start with your decoder installation, we strongly recommend
building a test track that uses a 20-ohm resistor to limit current. Only test
your installed decoder on the test track. The test track will prevent any
damage due to an incorrectly installed decoder.
TEST
All MRC decoders have been factory programmed with address #3, 28/
128 speed steps and maximum top voltage. After you have finished your
decoder installation you are ready to test it. Never run the installed
decoder on your layout without first passing the test. You may damage
the decoder if it is not wired correctly or if you have not properly isolated
the motor and lights.
Put the loco on the test track. Select the “Run” mode of your DCC system
and select or acquire address #3. Advance the throttle and the loco
should move forward. Push the light button, [F0], and the front headlight
should come on. Change the direction of the loco, the loco should
change direction and the rear headlight, [if equipped], should come on.
The locomotive cannot get to full speed, due to the resistor. If the loco
moved forwards and backwards, and the light{s} came on, you did a
great job. Congratulations!
Do not run the loco for an extended period of time on the test track or the
resistor will overheat.
*NOTE- If your installed decoder does not pass the test, find the problem,
correct it and test it again. As long as you test the decoder on the test
track there is little chance of damaging the decoder. Also do not confuse
a test track with a program track. A program track does not use the
current limiting resistor. Sound decoders need full power to the program
track to install all programming instructions.
DCC OPERATION
This decoder has diesel start up and shut down features. Press any
function key to start up the engine before operating the loco. To shut
down the engine you must bring the loco to idle and then press F8 three
times. If the loco is previously shut down you have to start up the engine.
You can use F19 to select 34 different horns and use F18 to select 1 of 8
bells. If you don’t have MRC Prodigy Advance DCC you will have to use
CV programming to select these features.
The decoder is defaulted to automatic notch. You can program CV122 to
3 to set manual notch for more realistic operation. Then use F9 to notch
up and use F8 to notch down. Using this feature gives you the true to life
feeling of operating a real locomotive.
There are many more programming features available with this decoder.
Please refer to the CV Chart to explore other features of the decoder.
DC OPERATION
This decoder provides synchronized, true ALCo diesel rumble
sounds with DC operation. Bells, horns, etc., cannot be accessed.
Use of the MRC BlackBox will enable the full range of sounds on a
DC system.
right pick up
mars light (red, blue and white)
motor
head light (black and yellow)
motor
left pick up
Figure1.0001803 decoder wiring diagram
DCC base unit
Power supply
Test track
27 ohm resistor
Figure 3. Diagram of test track
stand off- cut or tape
Figure2. 0001803 chassis diagram