Ringing signal generator
US4282410A · kind A · utility
13Cited by
2References
11Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 9, 1979 |
| Grant date | Aug 4, 1981 |
| Priority date | — |
| Expiry date | Apr 9, 1999 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04Q5/10
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A telephone ringing signal generator which sequentially produces a plurality of ringing signals each of a different frequency. Each of a plurality of tone ringers connected to the generator will ring only in response to it's particular frequency. A programmable oscillator generates the required frequencies under control of a time slot generator which defines the time slot during which each frequency is to be generated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.