Issued Patents 1989
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4819262 | Electronic gating control for manual telephone switchboard | Donald Lee Brittain | 1989-04-04 |
Showing 1–1 of 1 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4819262 | Electronic gating control for manual telephone switchboard | Donald Lee Brittain | 1989-04-04 |