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
Sound on / off
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.
*Note: We know that real S2/S4 locos do not have dynamic brakes,
but since most model railroads have steeper than normal grades, we
added this feature as an additional option.
left side pick up
right side pick up
left side pick up
right side pick up
DCC base unit
Power supply
Test track
27 ohm resistor
Figure 4. Diagram of test track
mill
mill
mill
mill
tape
tape
tape
tape
INSTALLATION
Refer to the instructions that came with your Atlas S2/S4 locomotive for
removal of the handrails, cab and body shell. Unsolder the four pick up
wires and unscew two screws. Don’t lose these two screws. Remove the
original circuit board and the weight. You have to modify the weight for
fitting in the decoder.
(Do not do any modifications to the weight while it
is still attached to the chassis or damage to the decoder or motor can
result)
Use a grinding wheel, belt sander, or a fine file, to modify the top
weight as shown in the photos. Make sure the weight is clean of any
debris before re-installing it in the chassis. Apply tape on the weight
except the two screw area to prevent any short circuit. The trimmed ends
of the pickup wire must be only 1/16” long. Too long will cause a short
circuit and damage the decoder. Solder the four pick up wires to the
decoder in the four spots, noted on the board as “pick”, [see photos].
Make sure that there are no wire strands or solder bridges that will touch
any of the decoder boards components or the weight after you install the
decoder. Note: Some early versions of the loco may only have 1screw.
Now, insure the single contact on the bottom of the decoder is bent at
approx 30 degrees to insure contact with top motor brush. Line up the
screw holes in the decoder, with the the modified top weight, and use the
screws to secure the decoder and the weight.
The narrow portion of the
decoder should fit snugly in the channel of the top weight.
The rear LED is set up at the factory to line up with the headlight lens in
the cab, if due to shipping the LED does not quite line up with the lens,
gently bend it back into position.
Re-install the body shell, cab, and handrails, and now your S2/S4 is ready
to go to work on your railroad.
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 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.
