This installation is for a Bachmann On30 14-Ton Two-Truck Stearns Heisler using a TCS MTC 21 pin adapter, WOW121 Steam Decoder, KA1 Keep Alive® and 28mm WOWSpeaker.
The Bachmann On30 14-Ton Two-Truck Stearns Heisler shown prior to installation.
First, remove two screws located underneath the cab and lift the cab from the chassis.
With the cab exterior set aside, remove the screw highlighted above in red from the top of the locomotive.
Inside, you will see this yellow capacitor. This capacitor MUST be removed to facilitate smooth running of the finished locomotive. Clip the leads and discard this piece.
Shown with this cap removed. With this complete, you can close this section back up.
Next, turn your attention to the coal bin. Carefully lift out the coal load and inside you will see the original decoder. Remove this decoder from the locomotive.
Underneath, you will see the original lighting board shown here.
Lift out this board and take note of the wiring layout on the bottom side to be sure to match the wires to the new installation.
Shown with a portion of the wire leads removed and the wiring layout illustrated. Removing just the speaker and track pickup allows us to swing this board out of the way of the install and utilize it's 'diagram' for the installation.
Remove the original speaker and replace it with the 28mm WOWSpeaker. We used a small rim of hot melt glue to secure it is place. NOTE: You must be very careful to avoid getting glue on the speaker cone. Glue on the speaker will ultimately cause it to produce no sound and fail.
With the speaker in place, solder the original wire leads to the new TCS 21 pin connector making sure the wire leads are in the correct locations. Here it is shown completely soldered including the KA1 Keep Alive. 1k 1/4 w resistors must be soldered in line to the negative lead on the LED(s) as the 21 pin adapter board does not have resistors. In this installation, as the space available is very limited, there is a fine balance in wire length. There has to be enough to work with, but not too much to crowd the installation.
Here the locomotive is shown complete. It is recommended to use Kapton tape to insulate the adapter board from the decoder and prevent shorts to the components on the bottom. All the wires are neatly tucked underneath the adapter board and decoder with the Keep Alive along side. All of these components must fit below the bottom of the coal load. With this complete, replace the coal load and cab and your installation for your Bachmann On30 14-Ton Two-Truck Stearns Heisler is complete.
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 than a 1/32 of an inch. When the wire gets tinned with solder, the insulation will shrink back more. Try to not expose any more wire than 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