Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5015961 | Frequency shift demodulator | Robert E. Springer, George F. Hafer | 1991-05-14 |
| 4878241 | Audio frequency interface for differential relays | — | 1989-10-31 |
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5015961 | Frequency shift demodulator | Robert E. Springer, George F. Hafer | 1991-05-14 |
| 4878241 | Audio frequency interface for differential relays | — | 1989-10-31 |