Patents per Year
Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date | Approx Value ⓘ |
|---|---|---|---|---|
| 6005921 | Telephone ringback test device and method | David Keefe, Jeffrey W. Hearsey, Michael Kennedy, Roy Lujan Soto | 1999-12-21 | $21,086,000 |
| 5680391 | Arrangement for testing telephone subscriber line circuit via B- | Onofrio Schillaci | 1997-10-21 | $8,906,000 |
| 5521959 | Programmable source for supplying controllably variable AC/DC voltage output for telephone line measurement apparatus | Richard L. Walsworth, Alex Knight | 1996-05-28 | $3,303,000 |