1968 300 horn fix

[JC68vert300]

One of my 2 horns is not sounding. It is the one closest to the fender that faces up. I tested the line and there is the full 12volts at the horn. I cleaned the connections. I removed the horn tapped it to see if I could loosen any dirt in it since it was upward facing. Both horns are marked the same....Sparton model U, neither indicates high or low note. They are the seashell shaped. Anyone have any other troubleshooting ideas? If I have to replace it, is it the high or low note?

 

[halifaxhops]

There is a screw with a 12 pt head I think it is, have some one hold the horn button down and turn it in then out if you hear anything you should be able to adjust it., some times they just get stuck, obviously take the wire off the other one.