Solid state alarm for clock-radio
US4166358A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 25, 1977 |
| Grant date | Sep 4, 1979 |
| Priority date | — |
| Expiry date | Mar 25, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG04G13/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A circuit provides a ramp voltage for purposes of controlling simultaneously a pair of transistors from saturation to cutoff and vice versa. Means are provided for generating an electronic strike and chime tone which is connected both to an amplifier circuit and the transistor controlled to cutoff. A tuner circuit which is part of the radio to provide a radio tone likewise is connected both to the amplifier and the transistor controlled to saturation. The circuit is provided with an enabling input at an alarm time and by dissipating the tones by varying percentages as the transistors change their state, a crescendo-decrescendo action may be obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.