Phase-measuring system using zero cross-overs between identical frequency waves
Abstract
Abstract A WAVE GENERATOR PROVIDES A SELECTED REFERENCE FREQUENCY WAVE. A SECOND WAVE, FREQUENCY-LOCKED TO AND SEPARATED FROM THE REFERENCE FREQUENCY BY A PREDETERMINED NUMBER OF HERTZ, IS ALSO PROVIDED BY THE GENERATOR. THE REFERENCE WAVE PASSED THROUGH EQUIPMENT FOR WHICH A TEST OF THE PHASE-SHIFT IS DESIRED. THE PHASE-SHIFTED REFERENCE WAVE IS THEN MIXED WITH THE SECOND WAVE TO PRODUCE A THIRD FREQUENCY WAVE. THE UNSHIFTED REFERENCE AND SECOND WAVES ARE ALSO MIXED AND PRODUCE THE SAME THIRD FREQUENCY WAVE. EACH OF THE THIRD WAVES IS SQUARED, THEN CONTROLS A CIRCUIT TO PRODUCE SHORT TRIGGER PULSES, THESE TRIGGER PULSES ARE USED TO START AND STOP A DIGITAL COUNTER, WITH THE COUNT RATE OF THE COUNTER GREATER THAN THE FREQUENCY OF THE THIRD WAVES. THE COUNT AS DISPLAYED BY THE COUNTER IS A MEASURE OF THE PHASE-SHIFT OF THE WAVE APPLIED TO THE EQUIPMENT BEING TESTED.
Inventors
- 👤 Donald E Maxwell
- 👤 Douglas R Houst
Bibliographic Details
Claims Analysis
Total Claims: 0References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-02-08 | 1974-08-10 | 1975-02-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-02-08 | 1978-08-10 | 1979-02-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-02-08 | 1982-08-10 | 1983-02-09 | $7700.00 | Window Closed / Lapsed |