Remove the Engine Cabin Roof (1 screw in back and 2 in front).

Remove the Cabin Boiler structure (4 screws under the Cabin). There are plastic cylinders glued directly underneath the cabin and I had to remove those also. The glue was soft, so I just wiggled the cylinders off.

As seen in the next photo the LGB engine control Printed Circuit Board (PCB) is exposed. You can also see where several years ago I had added 2 LEDs to light up the cabin: one is a red LED (that glows through holes I had drilled in the boiler door) and the second is a bright white LED that shines up into the face of Engineer "Bob"!

Slide the (green) cabin structure back away from the boiler as seen in the photo below (there are brass rods that run the length of the boiler and will slide out of the holding stanchions. You can remove the brass rods as they are only pressed into the plastic cabin structure. The LGB engine control printed circuit board will have 4 wires (brown and black for the front head light, white and black for the smoke unit) running to the front of the engine. There is a ribbon cable with 3 wires (white, brown green) coming from underneath the circuit board and running to the plastic engine block.

As seen in the picture below, all of the wiring is exposed (the circuit board sitting on top of the note book is the 75 Mhz on-board receiver).

With an ohmmeter I discovered that LGB wired one of the track power pickup leads to one of the motor leads. That is why there are only 3 wires coming from the plastic motor block unit instead of the 4 wires, which I had expected.

Remove the top of the Motor Block (remove 4 long screws and 2 smaller screws. The smaller screws attach to lead weights in the Motor Block)

The photo below shows the Motor Block with the top off uncovering the motor, connection posts, and gears. Notice the RED tab on the motor to the left side of the picture (if this is not in color it is the left side of the motor next to the single connection post). That single connection post is our problem child because it connects the port side track power and motor together (port: is left side as viewed from the train engineer looking into the cabin looking forward). This is a physical contact connection made by the motor resting on the post, not a wire that we can cut and splice into.

I then drilled a small hole in the motor block cover and ran my wire (green) out the top through the hole.

Here is the motor block cover sitting upside down with the wire pulled through the hole and the motor sitting in place. I then installed the motor block cover and motor back in place all at one time. Putting the motor in place and then trying to install the motor block cover did not work for me. The wire kept getting in the way of the installation.

Now I can wire the motor and track power independently to the On-board Receiver. Below is the description of how to connect the on-board receiver and the motor block.

- Track Power: I connected the port side track-power (which is the existing motor block post that we just isolated) to the Red, wire #7 called "Left Side Track Power Pick-up" in the manual. Then connected the starboard side track-power to the Black, wire #1 called "Right Side Track Power Pick-up".

- Motor: I connected the new Green wire coming out of the motor block (which is our port side motor connection) to the Orange, wire #6 called "Left Side Motor Terminal". Then connected the starboard side motor to the Grey, wire#2 called "Right Side Motor Terminal".

I left the original LGB printed circuit board (PCB) in the cabin to control all the LED lights and smoke device. There is a switch at the rear of the Mogul with three positions. Position (1) turns everything off (ie. no motor, no lights, no smoke), (2) turns on motor and lights with no smoke, (3) turns on motor, lights and smoke. When the smoke element is turned on, with switch position 3, the LGB PCB gets rather warm. Since my on-board receiver was going to be positioned on top of this board (as seen in the next photo.) I did not want all the heat, so I moved the switch to position number 2 (motor, lights, no smoke). I will turn to switch position 3 when I want smoke, but I usually run without smoke anyway.

Red Push Button: There is a push-button switch required for programming the 55491 receivers. It is supplied with a connector for easy removal, but it stands up rather high. In order to get the on-board receiver in to the Moguls boiler area I had to cut the connector from the push-button and solder the wires directly to the receiver's circuit board. It is a snug fit.

Programming Lights: Since I did not use the receiver to control the engines lights I needed to connect a light to one (front or rear) of the on-board receiver light controls. The receiver is setup to blink the train lights during programming. So connected a yellow LED with a 1 K ohm resistor to the "Rear Headlight" control and the "common" of the receiver. That way, I could see the blinking rate of the LED while programming, it would not be on while the engine is moving forward and when it came on while moving backward it would be a low intensity light and look nice.

Antenna: Wiring the antenna was another interesting effort. You do not want the wires of the antenna to cross over top of each other or you effectively shorten the antenna's receive wavelength, which in turn reduces your reception capabilities. Hence, you will have to be closer to the engine than normal. So I cut a piece of styrene to wrap the antenna wire around (staggered with out crossing over itself) and mount to the roof of the engine cabin. Figure 10 shows the notches I cut and how I wrapped the wire. I also made sure that the wire leading from the boiler to the antenna did not cross.

Well, that pretty much wraps up my LGB Mogul on-board receiver project. It's always fun digging into the guts of these train products and seeing how they are constructed. LGB seems to be Tops when it comes to a quality design.

Top of Page