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Santa Fe 485 with diesel roar and diesel horn

199 Views 4 Replies 3 Participants Last post by  howellsmithiii
My Santa Fe 485 with diesel roar and diesel horn does not work properly. Diesel roar is functioning great however the diesel horn is barely audible and not audible at all at higher speed. When I place the transformer in neutral position the diesel horn works loud and clear. Not sure if is a wiring issue. I've included some pics


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That looks like an aftermarket speaker you have there. If I remember correctly aftermarket speakers have a different resistance/impedance to the original speakers. I suspect this may be the problem.
I can’t remember now what the resistance/impedance is for an original speaker.
I do not see anything obviously wrong with the wiring. My initial guess would be there is a large voltage drop on the rails when the dual motor diesel is running that is not present when the diesel is in neutral. Causes of voltage drop can be one or more of the following items. Voltage sag at the transformer output due to the 4A current draw of the diesel. Solution, possibly a higher wattage transformer, 100W minimum is needed. Too small of a wire gauge, 16 ga minimum is needed with a power connection every 6' of track. Poor connectivity of the 690 track clips. Clean the sides of the rail flanges with sandpaper, bend the metal on the clip for a tight fit and attach it using a conductive, antioxidant grease. Track pins may not be clean and tight. They should be cleaned, I use sandpaper, make sure they are tight in the receiving rail and again use a small amount of conductive grease on the pins.
The total voltage drop due to the above items can be around 3.5V at 4A.
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This is the conductive grease I use for low resistance, long lasting track connections. There are other brands.

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Thank you for your responses. I am using a 22090 transformer and my track is hard wired every 4 sections with 14 gauge wire to the buss. Yes, that is an after market speaker I purchased from portlines. I will double check with Doug Peck. Of all the things I've done to make my layout great, I never inspected or cleaned the track pins. I will try cleaning the pins and apply a little dielectric grease. There are a lot of them. Sound like a good plan. Thanks.
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