H04Q 1/4535
With an additional signal transmitted for voice protection
Official title: {with an additional signal transmitted for voice protection}
H04Q1/4535 (With an additional signal transmitted for voice protection) appears on 3 US grants and 0 published applications in this corpus.
Search patents in H04Q- Granted patents
- 3
- Published applications
- 0
- Assignees
- 3
- Inventors
- 6
- Latest grant
- 19 Nov 1985
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1978 | 1 | 0 |
| 1979 | 1 | 0 |
| 1980 | 0 | 0 |
| 1981 | 0 | 0 |
| 1982 | 0 | 0 |
| 1983 | 0 | 0 |
| 1984 | 0 | 0 |
| 1985 | 1 | 0 |
By publication year. Applications have been published since 2001.
Recent patents
- Guard tone capture method19 Nov 1985US 4,554,542 AMotorola, Inc.
- Apparatus for detecting in-band signalling signals2 Oct 1979US 4,169,969 ASociete Lignes Telegraphiques et Telephoniques
- Telecommunication system with keyboard selection19 Dec 1978US 4,130,736 ASocieta Italiana Telecomunicazioni Siemens S.p.A.
No published applications in this class yet.
Most cited
By later US patents