This installation of TCS A6X Decoder is for HO Scale Overland HH660 and was performed by Craig Zeni, NC.
The first thing I did was check that the motor was isolated from the frame and found that it was. The engine came with 1.5v bulbs and a reversing light package from Overland - I stripped the reversing light package out and kept the two bulbs. The motor leads are flat phosphor bronze tabs that came up thru a plastic board and were soldered to metal strips on that board. The board and strips were removed. To secure the decoder to the motor I used some very sticky double sided foam tape on top of the motor and the motor lead tabs were bent over and stuck to the tape as well. I soldered orange and grey leads to the tabs then covered them with vinyl tape. I placed the decoder on the tape in such a way that it cleared the cab interior and the long hood ended - probably 3mm clearance on each end.
I made the motor to decoder connection, then the truck leads to decoder connection, then gave the unit a test run. Success! Ran fabulously. I then test fit the body and found it went on just right. I did put a bit of blue vinyl tape on the inside of the body to cover a low hanging bracket that used to hold the reversing light package. Otherwise I found enough clearance inside the body.
The lighting was a bit fussier. I took a lead from each bulb and soldered them together, then soldered a length of blue wire to them and fitted heat shrink tubing. I put a length of white wire on the front bulb's other lead and a length of yellow wire on the rear bulb's other lead, again using heat shrink tubing to cover the solder joints.
These added bits of wire were to allow enough slack to get the shell on and off the drive. They were then soldered to the decoder with white to front bulb lead, yellow to rear bulb lead, blue to the 1.5v pad. I try to orient the solder joints so that the wires will fold on themselves naturally and not interfere with the mechanism. Another test run, tweaking the lighting CVs and it's ready to go.
Important Soldering Tip
Please do not use any flux either liquid or paste on the mother board. Over time, the acidic properties of liquid or paste flux will begin eating away at the fiberglass PCB and will damage it. Use only Rosin-core solder or no-clean flux approved for electronics use.
TCS recommends the use of Kester "44" Sn63 Pb37, .015" diameter Rosin-core solder. Kester part number 24-6337-0007.
You can order this solder from the following retailers:
Digikey - PN:KE1110-ND
Techni-Tool - PN:488SO6775
Other solder tips
When stripping wire, only strip a tiny little bit of the insulation. Strip no more then a 1/64 of an inch. When the wire gets tinned with solder, the insulation will shrink back more. Try to not expose any more wire then half the length of the solder pad at most. In no case should solder or exposed wire wire ever be outside the boundary of the the solder pad you are attaching a wire to.
Click here for important information on properly Stripping and Tinning wire