Amplitude modulated high frequency signal detection device
US4637003A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 19, 1984 |
| Grant date | Jan 13, 1987 |
| Priority date | — |
| Expiry date | Dec 19, 2004 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03D1/10
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A high frequency signal detection device to be used in an information playback system for playing back signals from a record medium having a plurality of record tracks, includes first and second positive peak hold circuits having different time constant and a negative peak hold circuit. A difference circuit is provided to generate a difference signal between output signals of the first positive peak hold circuit and the negative peak hold circuit and an output signal of the difference circuit is compared with an output signal of the second positive peak hold circuit, to produce a high frequency signal detection signal. Thus, a very accurate detection signal is produced irrespective of the polarity of the input signal and whether or not the envelope of the high frequency signal is symmetric.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.