I've used a few train horns, but never wanted one on my truck. I was a locomotive Engineer for 42 years, I worked west out of Kansas City. Shortly before I retired in 2010, they taxied me and a Conductor to Emporia to pick up a coal train sitting in the yard, ready to go. We got ready to depart, talked to the dispatcher on the radio, got a signal to leave, attempted to hit the horn button for two shorts, and nothing came out but air. Long story short, someone had climbed up on the roof and removed the horn. I went up on the other unit, which was brand new, to see if I could remove that horn and put it on the lead unit, but the bolts were welded. And, it was facing the opposite direction, so we couldn't switch to the point. So we had to tie the train down, cut the power off, run it through the crossovers east of town, and take it three miles back west to turn the consist on the wye, change operating ends, and run it back east through the crossovers again, and back to our train and do another air test. Screwed around for two hours because of that. A friend who collects horns was a Conductor for Union Pacific. They came to his home with search warrants and would up terminating him because he had a UP horn in his collection and no reciept for it, He never did get his job back.