Kato GS-4 Tsunami Install

Parts Required:

2 x Surface-Mount LEDs (white)
2 x ¼ watt resistors
1 x Soundtraxx Micro-Tsunami 750 (heavy steam)
1 x 0.5" speaker
1 x Soundtraxx speaker baffle kit.
Thin sheet styrene (0.5mm)
Fishing sinkers
Double-sided tape

Tools Required:

Needlenose Tweezers
Needlenose Pliers
Soldering iron & solder
Jeweller's screwdrivers
Electrical tape
Multimeter
CA or other superglue
Drill bits
Black permanent marker
Hobby Knife

Instructions:

Part 1: Hardware

1) Dismantle the locomotive by lifting the cab roof off, followed by the cab. Grab the boiler assembly by the firebox and lift up, tilting towards the front. It should just slide off. Remove the tender shell by lifting up gently.

2) Remove the light board at the front of the locomotive, the clips that connect the contacts at the front to the frame, the plastic clip holding it in place and the two clear 'light conductors'. You won't need the metal clips connecting the light board to the frame. Set the light board aside for the moment.

3) Glue the shortest light conductor in place on the front of the plastic clip. Cut and glue three strips of the styrene across the black clip at the front (just behind the light conductor), middle – over the small hole, but keep the front cutout clear, and the rear. Use a 1mm drill bit to put the small hole through the stryene on top of it. Glue the longer light conductor back in place. The finished result should look something like this:

4) You will need to determine the correct values of the resistors for the LEDs you are using. One option is to remove the original SMD LEDs from the light board – the correct value resistors for these is 2.4k ohms. Be careful with these LEDs – the contacts for them break easily. The terminal with the green mark is the negative side.
An easy way to solder the SMD components to the resistor is to put a blob of solder on the resistor lead, then put the LED next to it, with the positive (unmarked) terminal next to the solder blob. Then, use the tweezers to push the LED into the solder while heating it with a soldering iron. Use the same method to attach a small length of wire to the negative side of the LED. One of the LEDs will have to be facing the body of the resistor, the other one will have to be facing away.

5) Superglue the LEDs in position behind the light conductors, both facing in the same direction, and with both resistors on the same side. As the Tsunami uses a common positive return (as do all other decoders), solder the resistor leads together. You should now have something that looks like this:



Put this back in place at the front of the locomotive.

6) Remove the weight from the tender and the black plastic cradle holding it.

7) Assemble the speaker baffle according to the instructions. There is only enough space inside for a half-size speaker baffle – the full size one will not allow the tender shell to go on properly. Install with the speaker facing downward, on the flat space at the rear of the tender. You will need to drill a couple of large holes in the tender floor for the sound to escape, and may need to file down some of the edging that holds the tender shell on.

8) The space occupied by the weight is where the decoder will go. Trim the rear of the weight cradle to just in front of the clip that holds it to the tender base. Glue some sheet styrene across the back, leaving at least 1¼ inches of the length clear.

9) Use some double-sided sticky-tape to tape the decoder in the space in the weight cradle, with the wires facing towards the fish sinkers. Feed the grey, orange, red and black wires through the hole just behind the sinkers.

10) Remove the metal strips running from the top of the drawbar to the top of the white circuit board in the tender. Leave them aside. Remove the white circuit board. There are two holes where the metal on the upper side runs through to the metal on the lower side. Using a drill bit, expand these holes slightly so that the connection between top and bottom is gone.

11) Feed the black and red wires through the holes in the white PCB, trim to length and solder to the two metal strips on the bottom, as below:

12) Trim the orange and grey wires to fit. Bend the two copper wires on top of the drawbar up slightly on the sides (these run to the motor), and solder the wires to them, with the orange wire on the right wire and the grey wire on the left wire.

13) Re-insert the white circuit board and replace the weight cradle, making sure none of the wires underneath get caught under the edges.

14) Trim the brown and green-yellow wires off the decoder and set aside – we'll use them later. Connect the purple wires to the speaker, and keep the excess aside.

15) Using a black permanent marker, colour the section of the blue, yellow and white wires between the tender and the locomotive black, to disguise them (optional).

16) Feed the blue, white and yellow wires up the side of the locomotive between the frame and the chassis, under where the cab clips in, with the blue wire on the same side of the loco as the resistors on the light board, and the white and yellow wires on the other side:

17) Run the wires along the side of the locomotive. They will not be long enough to reach the front, so use the wires set aside earlier to extend them, making sure to insulate the connections with electrical tape or heat-shrink tubing. Connect the extended blue wire to the resistors. The extended yellow wire goes to the other side of the front LED, the extended white wire goes to the rear LED. Ensure all connections are isolated.

18) Use the electrical tape to tape the wires clear of the motor and flywheel. Fortunately, the boiler has enough space to run the wires along the side of the chassis:

19) Using a 2mm drill bit, drill two holes in the front of the tender, almost touching each other, then use the hobby knife to conenct the two, as shown below:



This is to allow for ventilation for the decoder. Paint the edges of the hole black.

20) Put the boiler assembly back on, sliding it onto the front and pushing down on the rear. The back of it should just fit over the wires running down below the cab. Put the cab back in place, then the roof. Put the tender shell in place, and test the install by reading back CV1 – it should have a value of 3.

Troubleshooting:

There were 2 issues I ran into with this install

• The white circuit board in the tender was not contacting the metal strips sticking up beneath it. If this happens, apply a thin layer of solder to the metal strips on the underside of the board, so that it contacts the strips below. Then re-insert the board.

• The drawbar wires to the motor on may twist up and lose contact with the locomotive frame. If this happens, just push them back in place with tweezers, and put a drop of superglue on the top of the drawbar to hold them in place.

Part 2: Programming

There are issues programming Tsunami decoders on a Digitrax PR3, due to the inrush current of the decoder. To program a long address in the GS-4, you'll need to set CVs 17, 18 and 29. A calculator for the values of CVs 17 and 18 can be found here and a lookup table for CV 29 is here.

There are 2 options for the lighting controls:

Option 1; Mars light & Headlight on F0, forwards only:

Option 2; Mars light independently controlled:

Sounds

The Tsunami heavy steam contains the whistle and horn for SP GS-4 4449. setting CV 115 to 163 will set the primary whistle as the SP 4449 whistle, the secondary as the SP 4449 horn, with function 3 on and off toggling between them. CV 128 is the master volume control. the default value is 192.

Here's a demonstration of the finished product:

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