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These photos will show you a general way of installing the Tsunami Sound Decoder in a typical brass loco. It is normal for a non articulated loco for the decoder and the speaker to be mounted in the tender, so this is where I will start. This is the underside of the tender, I start by ensuring good pickup for the decoder. |
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I have removed one of the trucks and you can see the corrosion stains on the mating surfaces of the truck and bolster. This is a common cause of bad pickup. |
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I clean the surfaces with a wire wheel in a motor tool as shown. Do not use a cut off disk or grinding wheel as these are too harsh on the surfaces. |
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You can see that the surfaces are now clean and will allow good contact between the surfaces. |
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Before re-fitting the trucks I add extra pickups to the other wheels - never too many pickups. To do this I glue/solder a piece of circuit board to the truck as shown. PCB ties/sleepers are the best for this. Make sure all the surfaces are clean and free from oil/grease before gluing. |
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Here you can see the phosphor bronze wire soldered to the pcb. The wire is bent to rub on the back of the flange. I use 12.5 thou wire - it is light enough not to drag on the wheel but still make good contact. I have fitted pickups to the outer wheels, but, but if your paranoia insists then you can add a pickup to the center wheel also. |
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Both trucks have been modified, run a fine wire from one truck to the other and through a small hole drilled in the bottom of the tender. This will join onto the red wire from the decoder. |
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This is a typical brass chassis, spring mounted motor bracket and the draw bar connection from the tender. This loco has a bridge rectifier fitted to the motor. This is for the low voltage (1.5v)lamp in the headlight. This photo also shows the connection from the draw bar going to the top motor terminal - this will be the gray wire from the decoder. The bottom connection from the motor goes to the frame, this will be the orange wire from the decoder. The red decoder wire goes to the frame. The only 2 wires left here now are the headlight wires - they go to the blue and the white wires. As the lamp is 1.5 volts use a 680 ohm resistor in one of the wires. |
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While working on the chassis check for possible shorts. This photo shows a very common source of shorts - the brake shoes or brake hangers. they are very easy to bend when you are working on the chassis and can contact the wheel when it moves to the side when going around corners. |
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I make my own speaker boxes from 1mm styrene (40 thou)as shown. Using the method shown will always give a good solid joint at the corners. The extra bits can be removed when all the glue is set. |
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Here you can see the finished box, less the cover. The wires enter through the holes drilled in the end and solder to the terminals - these are the purple wires. The box can be mounted facing down through the bottom of the tender or facing up through the coal load. On some Vanderbilt tenders there is no place to drill holes - so don't!! Try it without the holes and see what you think... |
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I mount the decoder in the tender and run the wires to the loco through holes drilled under footplate. I only fit plugs as a last resort. The photos were taken of this loco, a T&P 2-10-2.
With some articulated locos it is possible to mount the decoder and the speaker in the boiler. I mounted them this way in an AC7 Cab Forward (Wow the air pumps on this one are out of this world) and a GN 2-8-8-2 R2 - this was scary down hill as it has a rare gear box that allows the loco to freewheel down hill - a case for F7 to actually apply the brakes!! |