With a lot of reading and help from several people I was able to :
Create a sound file using sound clips from on-line
Downloaded that file into an ESU project #S0811 (EMD SD80 sounds)
Replaced coupler clank with the new special horn sound that I created
Mapped the sound slot to f3
Saved the SO811 sound project
I do not have a decoder as yet but since this is going into a KATO SD90 I will use an ESU LS V5 Nano with a sugar cube speaker.
Here is a 2 minute Y-T video to demonstrate what I have done. Keep in mind the sound is not coming from the decoder, in this case I dubbed the wav file onto the video file. The additional horn will be used for road crossings or for folks on the rails and used sparingly. This should go over well with kids at the annual Fair show. I will probably run this loco and my special caboose, for special trains that I want to emphasize a certain subject or issue.
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