Issued Patents 1989
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 4855971 | Time adjustment arrangement for digital displays | Karlheinz Hammelsbacher | 1989-08-08 |
| 4841493 | Electronic acoustic signal emitter | Erwin Potthof, Henry Fluhrer | 1989-06-20 |