I've had this diaphone for a few years now and cleaned it up all the patina that accumulated on it over the years. I also cleaned out the stator and checked the piston. This project took a lot longer than I anticipated because I never got the correct parts I needed to get the proper air flow from the compressor to the horn. I finally got everything right and was able to test it. It sounds fantastic. This diahone has an aluminum piston I do not know how many ounces since I did not weigh it. I also had the air compressor set at 40 PSI. It has been said that the aluminum pistons should be no higher than 35 PSI. With brass pistons, it is said that you could pump it up to a hundred PSI with no problem apparently.
