Crystal sync

A system for generating a sync signal that will ensure proper synchronization of film footage and its corresponding sync sound without using any sync reference, such as 60Hz AC line frequency. Two piezoelectric crystals, each tuned to the same high frequency, are installed in the camera and recorder. The crystal in the camera precisely controls the motor speed during shooting. The crystal in the recorder produces a pilot tone that is recorded on tape in the same way which the camera motor speed would be recorded through the conventional sync cable. Because the two crystals are tuned identically, the dailies, when synched with the magnetic film copy of the original sound takes, will maintain perfect sync once the slate marks are aligned. Crystal sync generators are also installed in portable video cameras and VTRs. See Nagraneo-pilot.