This installation is for a HO Scale Walthers Life Like GP7.
With milling of the frame, DXI has been able to utilize a using a TCS WOW121-Diesel Decoder, AS-MB2 NC Motherboard, KA4 Keep Alive®,
UNIV-SH1-C WOW Speaker Kit.
The upper picture shows the Walthers Life Like GP7 with its shell on.
To start off this install, we must first remove the front and rear coupler screws highlighted above and their housings.
With the couplers removed, while gently pulling outwards at each end and along each side of the frame, lift the shell off of the frame.
Take care to release the handrails as you lift off the shell so they don't break.
Walthers Life Like GP7 shown with the shell off. Remove the wires from the original lighting board and remove it from the chassis. Clip off the original LEDs and
prepare them for reuse by splicing wired leads to them.
The Walthers Life Like GP7 shown with the shell off.
With the original lighting board and other components removed, trim, tin or lengthen the wires as necessary.
Using small lengths of TCS 3/32" and 3/64" shrink tubing, insulate these wire leads if needed.
To allow a space for the motherboard and speaker, the frame must be milled as highlighted above to keep all the components below the original top of the frame.
To remove the frame from the chassis, first remove the two screws highlighted in red above, one from each end.
Next, remove the fuel tank and the two brass screws located inside the fuel tank. The frame will lift off the chassis now.
Remove the small track pick up screw from the frame and save for later reinstallation.
The frame shown properly milled. Reinstall the frame and secure it with the removed screws. Reinsert the track pick up screw as well.
The locomotive shown reassembled properly after milling.
Using double sided foam tape, mount the AS-MB2 NC to the frame and solder the motor, and track wire leads according to the included wiring diagram.
With the 35mm X 16mm WOWSound speaker inserted into the UNI-SH1-C enclosure, using double sided foam tape, mount this assembly to the frame as shown.
If your speaker enclosure installation covers the portholes on the enclosure, we recommend adding new port hole(s) similar to the original porting. Be sure that the new portholes are the same size and amount of the original and are vented freely into the locomotive We have found introducing a port of the correct size greatly increases the volume and sound quality of the installation. Too much or too little porting decreases the sound quality.
Using the same double sided foam tape, secure the KA4 Keep Alive® to the frame as shown above. Solder these wire leads to the motherboard.
To fit the new LED to the rear light tube, it's length must be trimmed as shown above with a small saw.
With the new LED spliced into wire leads, using a small dab of hot melt glue, secure these LEDs to the front and rear light tubes as shown above.
Solder these wire leads to the motherboard according to the included wiring diagram.
We have found that LED light output is brightest when shinning directly into the end of the light tube, but in some circumstances they may be placed along the length
of the tube as well with satisfactory results. In doing so, white light LED output would be least affected, while non-white LED output will be more affected by placement.
TCS motherboards include onboard current limit resistors for LED use. There is no need to apply external resistors for LED use.
The installation shown complete. When fitting the shell, we decided it best to route the rear LED wires under the speaker. We carefully lifted the speaker as to not
disturb the double sided tape and then cut a small channel into the tape, reattached the speaker gently on top of it.
You can now plug in your WOW121 decoder.
Lastly, in order to keep the wires neat and prevent possible shorts, lace the wires into a bundle using lacing cord.
Now you can close up the locomotive and reinstall the coupler assemblies. Be sure to be mindful of wire routing and reassembly of the shell as to not damage
or foul the installation. Your Walthers Life Like GP7 is now WOWSound equipped and ready to roll!
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
In order to keep the wires neat and prevent possible shorts, we recommend lacing the wires into a bundle using lacing cord. Lacing cord is a wax impregnated string used for wire bundling and making harnesses. There are many choices of lacing cord available from Digikey www.digikey.com.
We use part number 802534B BK032-ND