Rattle or ratchet?

Carraca - Autor: MONDA, FE Y TRADICIÓN (2006)

A dictionary of 1905 says: "Ratchet: Instrument wooden Catholic churches used to call the faithful on certain days of Holy Week." And again we read, "Rattle: Woodwind instrument that produces an unpleasant noise and replaces the bell at Easter".
However, these different instruments, both in its size and use. The ratchet has a gear that sounds one or more sheets of wood. And is not always used for Easter.