Issued Patents All Time
Showing 1–12 of 12 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5331288 | Railroad rail signal receiver having frequency conversion and a resonant tuned transformer secondary | — | 1994-07-19 |
| 5030886 | Self-checking circuit arrangement for operation of a searchlight signal | — | 1991-07-09 |
| 4763017 | Electronic bipolar interface circuit | Richard D. Campbell | 1988-08-09 |
| 4641045 | Fail-safe one and only one signal checking circuit | — | 1987-02-03 |
| 4623850 | Vital code generating circuit | — | 1986-11-18 |
| 4401970 | Vital lowest speed command selector | — | 1983-08-30 |
| 4384250 | Vital vehicle movement detector | — | 1983-05-17 |
| 4368440 | Fail-safe low-pass filtering circuit | — | 1983-01-11 |
| 4315208 | Regulated power supply having its d.c. voltage source selectively supplemented by a d.c. to d.c. converter | John M. McElroy | 1982-02-09 |
| 4314234 | Test set for railway cab signal system | Joseph J. Pierro, Jr. | 1982-02-02 |
| 4314237 | Fail-safe acknowledging circuit | — | 1982-02-02 |
| 4314306 | Signal-powered receiver | — | 1982-02-02 |