I'm in the need for an overhead/gantry crane alarm.

I would like a nice 3 tone intermittent alarm. I know I have heard them before especially in the south in some of the big offshore yards, but I cant find the one I am looking for.

I want something that is loud, but semi-pleasent to listen to as the bridge moves from one end of the plant to the other. I dont want to drive people nuts, just notify them of the movement.

Any help would be greatly appreciated. Im brand new to this site...looks pretty cool.
Thanks in advance.
-Pete
pnicklas@sunsetmetalworks.com