My "new" 1915 T has a klaxon horn that is loud but doesn't seem to have the classical sound. I always thought that there was a screw in the center of the vibrator inside the trumpet that you could adjust the sound. Mine seems to have a rivet. Is there an adjustment to these? Do you have to take it apart to adjust?
R.S. The hand Klaxons / Klaxonette have a shaped bump on the inside of the diaphragm that a toothed wheel rides on.. The part you see is the end of that bump riveted over to hold it in place. The only adjustment are the two screws on top, by the oil filler. These allow you to mover the mechanism inside closer or further from the bump. Play with it a bit until you get the sound you want.