Function
Idle/Moving
F0
Headlight on/off
F1
Bell on/off
F2
Horn
F3
Air release
F4
Coupling
F5
Brake release (idle) / brake squeal (moving)
F6*
Dynamic brake on/off
F7
Air hose firing/uncoupling lever
F8
Click 3 times w ill shut dow n / notch dow n w hile CV122=3
F9
Engine cooling fan / notch up w hile CV122=3
F10
Rail w heel clack (only moving)
F11
Traction air compressor
F12
Change Prime Mover Type plus Sound on / off (see CV#123)
F13
Short air release
F14
Flange noise
F15
Air pump
F16
Associated loco sound
F17
Flange noise
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
Coupling
F25
Air release
F26
Flange noise
F27
Air hose firing
F28
Air release
Note- Bell, Dynamic Brake, and Rail-Wheel Clack, cannot play at the
same time.
motor
front light
left pick up
left pick up
rear light
DCC base unit
Power supply
Test track
27 ohm resistor
Figure 3. Diagram of test track
INSTALLATION
Refer to the instructions that came with your Athearn RS-3 locomotive for
removal of the handrails, walk way and body shell. Remove the plastic
clips that hold the wires to the original circuit board and note where they
go. (Note: there is a short length of wire for the right side pick-up that is
attached to the circuit board with one plastic clip, the other end of this wire
is secured to the chassis under the original circuit board by one of the
hold down screws, this short length of wire is not needed for the decoder
installation, as the decoder will pick up right side current when screwed
to the chassis). Don’t lose these clips, you will need them to re-attach the
wires to the decoder tabs. Remove the two screws that hold the circuit
board to the chassis, remove and discard the original circuit board, with
the short length of wire mentioned above. Apply tape on the top of the
motor to prevent it from touching the decoder. Install the sound decoder
with speaker facing down along the long hood end of the loco. Use the
two original screws to secure the decoder to the chassis. Re-attach the
wires to the decoder with the plastic clips. Make sure there are no stray
strands of wire crossing any of the tabs on the decoder, or this can result
in a short circuit damaging the decoder.
Refer to the decoder wiring diagram below. There is no right side pick up
tab shown on the decoder. the right side pick up is made through the two
screws that hold down the decoder to the chassis.
The Athearn locomotive uses 1.5 volt bulbs and the decoders lighting
circuit is set up to use these bulbs without any modification. Before re-
installing the locomotive body shell, walk way, and handrails...test the
locomotive on a test track to check for proper installation and operation of
the decoder.
This decoder was made to fit the Athearn RS-3 without any modification to
the body shell. Please check clearances inside the body shell as there
maybe some variations in the different roadnames.
If there are no visible obstructions inside the body, replace the walkway,
body shell and handrails. Now the locomotive is ready to go to work on
your layout.
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. In real life the notch level has noting to do
with travel speed.
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 244 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.
Figure 1.
Figure 2.