An electroacoustic transducer employing a polymer connection for maximizing volume displacement. A projector installation fixture is mounted on a side end of an upper surface panel of the table or the desk near the projection surface, and a front-projection projector is detachably installed in place by the projector installation fixture. The first edge device may add a start time to the test data indicating a start of a measurement instance using the test data, transmit the test data to the second edge device over the interface, receive the test data with a receive time added by the second edge device, and store at least the start time and the receive time as handoff performance data. In a second aspect of the invention, the storage unit is positioned above an outlet of the household water system and is introduced by gravity. To grow large boules of AlGaN, preferably multiple Al sources are used, the Al sources being sequentially activated to avoid Al source depletion and excessive degradation.