hello. I put a digitrax sound chip into an a class and also a 141. I cant remember right now which one but it was a budget preloaded chip that happened to have the same engine as was fitted to the 141 s . (american) the horn obviously is all wrong. I intended to visit Downpatrick on the modellers open day and record some sounds to fix it up, but couldnt go in the end and pretty much forgot about it till i saw this post !!! I just used an adapter lead to feed from the 21 pin. I got a little power drain but never got to the bottom of it.