Athearn HO U50 Sound install

woodone Nov 14, 2011

  1. woodone

    woodone TrainBoard Member

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    Just finished doing a sound decoder install into a HO Athearn U-50. The decoder is the new decoder from SoundTraxx, (827124) for the dual FDL-16. The install is a straight forward install by using the JST 9 pin socket. You must remove the original harness from the decoder so it will plug into the JST plug. There a places for two speakers (30MM). One front and one rear. I installed two and hooked them up in series. I put this all together and tested. First off the lights were so dim that you could not see them without turning off the room lights. I wonder if Atheren will ever start using LED’s. Second was the volume. It was very weak. After thinking about this (poor volume) I realized that the see through grills on the sides and the top were letting all my sound waves escape. The blower detail over each speaker leaves little room to construct an enclosure. I decided to build some clear inserts to put into the grill openings to close off the grill but still be able to see through them. I also blocked off the roof grills with some black styrene. I used the black because of the red glow (a red LED on the decoder) was visible through the rear grill. Now the shell of the locomotive is a large enclosure.
    Changing the bulbs to LED's. I installed 6 surface mount LED's. They look much better.
    After testing the second time I removed the two roof grill block off plates. I got better volume without them in place.

    I ended up just using a black pen to dull the red LED on the decoder which was visible when you had the headlights on.
    One other thing I learned on this install. I tried to use the 8 pin socket for my lighting. Buy using a 8 pin pug with my blue, ¤¤¤¤e and yellow light wires coming off the plug. When I did this all of the LED's were lite up very dimly. I had to remove the 8 pin socket wires and hook my lighting wires right to the blue, white, yellow and violet wires coming off the decoder. That solved the dim LED's. There must have been some sort of feedback coming from the original light board.
    I sure wish Athearn would use LED's for the lights!
     
  2. UnionPasific

    UnionPasific TrainBoard Member

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    nice sharing,...i also have ATHEARN U50 but use replace all board to make easy arrangement instead of narrow space. would you upload the picture please.
    Thanks
     
  3. woodone

    woodone TrainBoard Member

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    Sent you a PM.
     
  4. lexon

    lexon TrainBoard Member

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    There is never, ever any feedback. The resistors on the PC board must be higher than normal value which is usually around 1k. Measure the resistance.
    I do know many on board loco PC boards use above 1k.
    Some can be over 2k.
    Are the original bulbs, 1.5 volt or 12 volt? There are times light bulbs provied better light charateristics than LED's

    Also, post photos via Photo Bucket. I know there are others who will wonder what your install is like. It may convince others to buy the loco which will help Athearn.

    We are a huge model railroad community because of the Internet.
    Rich
     
  5. woodone

    woodone TrainBoard Member

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    Rich,
    On the lights, Athearn uses 1.5 bulbs. I replaced the bulbs with surface mount LED's. I used the 8 pin socket to provide the power and the function for the LED's. The blue wire was my power with 1K resistors to each LED. Then I pickup up the white for the headlight function, the yellow for the rear. These were all coming off the 8 pin socket on the original light board. I also pickup a green (f5 function) for the Mars light but that came off the decoder itself. When I powered up the unit all the headlights and rear lights were on, only very dim. I don't recall if the Mars came on or not. I moved the function wires to the decoder wires and the lights went out.
    I don't have a photo bucket so no photo's. Sorry.
     

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