Issued Patents All Time
Showing 1–2 of 2 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5748637 | DTMF signaling on four-wire switched 56 KBPS lines | Daniel M. Joffe | 1998-05-05 |
| 5457690 | DTMF Signaling on four-wire switched 56 Kbps Lines | Daniel M. Joffe | 1995-10-10 |