Issued Patents All Time
Showing 1–3 of 3 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 8335326 | Communication method for vacuum tube replacement devices | Douglas H. Roberts | 2012-12-18 |
| 7482863 | Expanded performance and functions for vacuum tube replacement devices | Douglas H. Roberts | 2009-01-27 |
| 7286060 | Indicators for vacuum tube replacement devices | Douglas H. Roberts | 2007-10-23 |