Replace A Soundtraxx Sound Value with a BH-2 Decoder in a Bachmann 2-6-0

Jim Exler, Nampa, ID May 9, 2023

Steps to Remove the Tender Shell.

1. Disconnect the wiring connector under the rear of the locomotive by pulling straight down.

2. Lift the drawbar off of the toggle pin on the tender and they are now separate.

3. There is a plastic retaining clip for the wires at the toggle pin. Remove the two screws and the clip.

4. There is a screw under the wires holding the shell on. Remove the screw holding the front truck of the tender so you can move the truck slightly back to clear the shell screw being careful as there is a pickup wire attached. Spread the wires from the connector behind the pin and remove the shell screw.

5. Lift the front of the tender shell to clear the two clips at the rear and remove. You are in.

6. I would temporarily replace the front truck screw to retain the truck while working on the model to prevent tension on the pickup wire.

The three views above show the tender with the shell removed and the original Sound Value board in place. Three screw hold the board and one for the rear light.

Here are 2 views of the replacement Soundtraxx BH-2 steam decoder. The connection points on this board match the Sound Value exactly. It is a simple process to move the wires in pairs (due to the retaining clips) from one board to the other. Be careful as Bachmann uses mostly black wires. (see next caption below)

This shows the BH-2 with the wires attached and the speaker. Bachmann does not use standard colors for their wires so you may note some paint blotches on selected wires for identification. A simple task to prevent a mis-connection that might let the "magic smoke" out of the decoder.

Here are 2 views of the model, ready to close. The original Sound Value board is pictured also. Make sure all the wires are tucked in out of the way to clear the shell.