Amplitude stabilized oscillator circuit
US5801592A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 21, 1997 |
| Grant date | Sep 1, 1998 |
| Priority date | — |
| Expiry date | May 21, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03B5/1234
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
An oscillator circuit is provided for stabilizing the amplitude of a HF oscillation of an audio signal. In such an oscillator circuit, an audio signal having a frequency in the range of 20 Hz . . . 20 kHz is coupled into the oscillator circuit, is modulated with a high frequency and is emitted in the form of an RF audio signal having a frequency of more than 2 MHz. Such an oscillator circuit is used for instance in an infrared transmitting unit, wherein a low frequency audio signal is transformed into a higher frequency infrared signal. The higher frequency audio signals are transmitted via infrared channel to an appropriate receiving unit--for instance to infrared head phones--which comprises a receiving unit having an appropriate demodulator and preferably also a stereo-decoder in order to reproduce the low frequency audio signals. The oscillator for stabilizing the amplitude of a high frequency oscillation comprises a resonant circuit which is coupled with a first transistor having a base terminal, an emitter contact, and a collector contact. The first transistor develops an output voltage at the emitter contact which is fed back into a base circuit of the first transistor. The …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.