Abstract: A method for applying a waterproof coating to a transducer component includes the steps of cleaning and promoting bonding on the transducer component by immersing the component in a mixture of isopropyl alcohol, deionized water, and siline. The component is then air dried and rinsed in pure isopropyl alcohol. After drying, the component is vacuum baked and subjected to a vacuum for twelve hours. A parylene coating is provided to the component surface. The parylene coating is abraded, and the surface is rinsed with pure isopropyl alcohol. After drying, polyurethane is provided on the abraded parylene surface. The polyurethane is cured to form a waterproof coating on the transducer component. In further embodiments, a second parylene coating can be provided outside the polyurethane.

Abstract: A hydrophone is provided which includes at least four piezoelectric sensors mounted to a central section of syntactic acoustic dampening material as well as a layer of corprene between the piezoelectric sensors and the central section. Each of the piezoelectric sensors includes radially poled piezoelectric cylinders wired in series with inert polycarbonate endcaps and an isolator layer. The piezoelectric cylinders are assembled co-axially. The piezoelectric cylinders are then adhered to the central section and sandwich a layer of corprene. The corprene also adds noise dampening properties.

Abstract: A method of assembling a hydrophone is provided in which the method stacks ceramic rings, delrin washers, and LC-800 washers such that a top edge of a composite stack extends beyond a top of a hydrophone flange. By measuring the voltage on each ceramic ring while an end cap and a socket head cap screw are installed; the axial compression of each ceramic ring is quantified; thereby, providing an opportunity to equalize the axial compression of each ceramic ring to yield an accurately performing hydrophone.