Living in Montreal near the Montreal West train station when I was a kid, I got to see many commuter trains. I saw a lot of F units pulling double decked cars and of course, RDCs! Many many RDCs. When Proto 1000 brought theirs out I wanted one. I never did buy one. Fast forward and Rapido announces theirs. Nice but not in my price range. As predicted the Proto models came on the market and I picked one up quite inexpensively. I saved my allowance and bought a Rapido/ESU decoder when they became available. This is the explanation with pictures of how I went about installing the decoder. Before I go any further I have to acknowledge the work and installation photos of Bevis King who did a non sound install and provided excellent documentation of his efforts. See: http://www.bevteccom.co.uk/Rail/DCC/P1k_RDC.html
All installations begin with the removal of the shell. Remove the small phillips screws holding the coupler cover plates. Note that along with the couplers, there are 4 screws holding the shell to the metal frame. See Fig.1 & Fig.2
Once you have the shell off, you are probably faced with a long circuit board with a bunch of diodes and a large resistor soldered to it. This is an attempt at constant directional lighting for DC control. All components must be removed. See Fig.3
I used my soldering iron and a screw driver to melt the solder and pry up the component. This only worked marginally well. I did a considerable amount of damage to the solder pads. Not a big issue but we do want to reuse a few of them. You may have better luck using solder wick or a solder sucker to remove as much solder as possible before removing the component. Whatever method you use, exercise care to do as little damage to the circuit board traces as possible. See Fig. 4
Also in Fig. 4 you will notice a bunch on X’s on the board. If you want to use the circuit board as a base for the DCC install, the traces must be cut at these locations. See Fig. 5
I chose to remove the incandescent lighting and convert to LED. To remove the stock lights remove the plastic wire retainers as shown in Fig. 6 and Fig. 7 and remove the bulbs. The locations are marked FL1, FL2, RL1, RL2. For the rear light, you will have to take out the screws holding that end of the board and lift up slightly to let the wires free, see Fig. 8. I replaced the bulbs with 3mm LEDs.
I like to use a 1k resistor on the LEDs so I utilized part of the circuit board to do so. I placed a resistor at D4 and D7 locations. By using a solid link where the old resistor was on the board I created a kind of Blue Wire bus. The blue wire of course is the positive common for lighting and Auxiliary outputs. See Fig. 9 for the placement of the 1k resistors and the solid link.
I wanted interior lighting and so I purchased some self adhesive 12v strip lighting. I simply cut a length of it and soldered blue and green wires to it and stuck it to the underside of the circuit board. To make sure I didn’t overload the aux 1 output of the decoder I measured the current which came in at about 56mA, well below the max for the aux output. See Fig. 10
As a precaution I removed all the plastic wire retainers and soldered the connections. This ensures that there will always be a good connection.
I like to use 21 pin decoders for a variety of reasons. To facilitate the 21 pin decoder I use the ESU #51967 adapter board. This allows me to solder everything up without the decoder attached and if I ever need to replace the decoder I can easily do so. I can also remove it to connect it to my ESU decoder tester, which I connect to my LokProgrammer. The board it attached with double sided tape. See Fig. 11 & Fig. 12
Note the DCC color code for the connections are as follows:
P1 Orange Motor +
P2 Yellow Rear Headlight
P4 Black Left Rail Power
P5 Grey Motor –
P6 White Front Headlight
P7 Blue Positive Common
P8 Red Right Rail Power
The diagram for the 51967 Adapter board is shown in Fig13. Note that if you want to have powered auxiliary outputs 3 and 4 you can use ESU # 51968 adapter board which comes with the necessary transistors.
I had to figure out where to place the speakers. There is plenty of room over the circuit board but where is the sound going to go? I considered drilling out some of the blister and replacing it with some kind of mesh but in the long run chose to use the ends of the frame. At this location there are open spaces by the steps where the sound can escape. See Fig. 14 & Fig. 15.
At the rear end of the RDC, the fit is kind of tight where the speaker goes in so I had to remove the rear of the top step to accommodate the speaker when replacing the shell. See Fig. 16.
The speakers are wired in parallel, see Fig. 17.
Plugging in the decoder finalizes the installation. See Fig. 18.
Aux 1 is set to the ditch lights as it comes from Rapido. I used JMRI to change the function of Aux 1 to work in both directions, not just forward and also reduced the brightness of the output to 0 (zero) otherwise it was much too bright. See Fig. 19 and Fig. 20.
Further programming is needed for the sound levels as I find some of the sounds VERY loud and with the two sugar cube speakers the overall volume is too much. I will do this with the LokProgrammer.
Please see the video for a demonstration with the sound levels set from the factory.
Please comment any questions, suggestions or corrections. Thanks for looking.