Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5521903 | Port system for interfacing digital PBX to digital transmission facility | Michael J. English, Michel L. Hearn, David M. Kissel, Douglas A. Spencer, Jeffrey A. Williams | 1996-05-28 |
| 4493073 | Maintenance of stored program controlled switching systems | Ronald K. Witmore | 1985-01-08 |