Quantum Aristo PnP Sound and Power Decoder Installation in the RDC
by Greg Elmassian
You remove one of the square compartments underneath. See the picture above. They both look the same, on has the Aristo socket, the other a socket for the speaker, and another socket. Just loosen the screws, do not remove them.
The easiest way to do this is open the car, and unplug the speaker plug from the circuit board. There are 2 sets of wires going from the chassis to the shell. The red and black wires are the smoke unit, the two black wires are the speaker.
When you are inside you can remove the MU wires, in this (poor) picture, at the far back left, you see 2 solder pads and black wires, that's one MU cable.
On the right side at the back, behind the bulb, you see two more, that's the other MU cable. I remove them since I don't use them or want to look at them, or have them snag on a switch.
Again, the speaker wires come down from the top, and plug into the board, just to the extreme right in this picture, you can just barely make out the plug with the back wires. Pull this plug from the board.
Now thread this wire and connector down to come out next to the Aristo socket. Button the chassis back together. You can see the wire and plug from the QSI and the speaker wire you threaded through in this picture:
Now use 2 short pieces of wire, like 1/4 watt resistor leads to "jumper" the QSI speaker plug to the 3 pin Aristo speaker plug.
When reinstalling the compartments, tighten the screws GENTLY, otherwise you will snap the slotted tabs off.
Visual Improvements
Pete Eggink has done some neat stuff with his - click here for Pete's RDC page. Basically he lowered the car, rotated the underbody detail 180 degrees to match the prototype, modified the air tanks.
Improving Running
Several people have reported that swapping the trucks such that the rigid axle is towards the center and the floating axle is towards the couplers helps. My opinion is that part of the trouble is the traction tires "grabbing", so I would try this AFTER you swap out the traction tires for regular wheels.
If you do this, you will basically have the car running opposite to the directional lighting, so you may have to reverse the motor leads inside.
From Jeff Cairns: "I sort of went crazy with mine, and ended up making aluminum leaf springs to prevent derailments! The springs go between the chassis and the truck's A-frame, thus enabling the car to rock side-to-side. They can actually handle 4 foot diameter turnouts at full throttle now!"
