Attempting to relocate underwater objects in open ocean or a low visibility environment can be a difficult and time consuming task. Acoustic pingers and transponders solve this problem. These acoustic beacons are attached to an underwater site or instrument package and transmit a sonar signal. A gun-like device, either carried by a diver or deployed from a boat, detects the signal and guides the operator directly to the beacon. Today these acoustic devices are being employed by many marine scientists and researchers to keep track of expensive oceanographic equipment allowing instruments to be quickly relocated and retrieved.