| | Class Definition for Class 331 - OSCILLATORS |
 | | A system for initiating and maintaining oscillations whose frequency or period is fixed or determined by the physical parameters of the system. |
| | The fundamental elements required by an oscillator system are: (1) a frequency or period determining element, such as a resonator or timing means, (2) a driving system for the frequency or period determining element, and (3) means for deriving a useful output from the oscillator system. |
| | for systems for measuring the frequency of a cyclic current or voltage by phase comparison with a standard cyclic current or voltage, and subclasses 76.77+ for systems for measuring electricity utilizing phase comparison means (e.g., phase comparison between cyclic pulse voltage and sinusoidal current). |
| www.uspto.gov /go/classification/uspc331/defs331.htm (4602 words) |
