I've still got some old horns in a box somewhere. There were several different kinds. There was one big honking mofo that Acme(I think) put out, called "The Bugle". There were smaller ones, including models attached to a wrist bracelet. Some were one-piece and had reeds built in; earlier models came in two parts and had reeds that screwed on and had to be replaced 2/3 times a year. It wasn't uncommon to have a reed start to go during a game too. You'd end up getting a toot that sounded like a duck being strangled.
Horns were a pain in the azz. Invariably ballplayers would stop when they heard one. And invariably new officials would get confused now and then and blow their whistle on an in-play penalty instead of the horn, thus killing play. I had that happen once on about a 65-yd. TD run. Not only did it kill the play before the runner scored, the damn penalty was for a defensive personal foul. Naturally, the home team was the team about to score too. As the white hat, I had the pleasure of trying to explain that one to the head coach. Note that I followed "team unity" principles though; I pointed at the official who blew his whistle and told the coach "That's the azzhole who did it."