Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4820996 | Amplifying arrangements | Roy Heppinstall, George I. F. Tupper, Edmund K. Tunstall | 1989-04-11 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4820996 | Amplifying arrangements | Roy Heppinstall, George I. F. Tupper, Edmund K. Tunstall | 1989-04-11 |