As I was working on our review of sound signaling devices in our August 2016 issue, I took a look on the web for homemade foghorns. I found quite a number of websites and videos that showed how to make foghorns and train horns out of common plastic pipe and fittings. A trip to the hardware store for some 1/2″ PVC pipe and fittings, and 30 or 40 minutes of puttering in the shop was all it took to come up with a few configurations that made a sound that I liked.
Read more in our August 2016 issue: smallboatsmonthly.com/article/little-big-horn/