Deflection system with overscan protection
US3940661A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Feb 10, 1975 |
| Grant date | Feb 24, 1976 |
| Priority date | — |
| Expiry date | Feb 10, 1995 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N3/223
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
In a deflection system including an oscillator and an amplifier providing scanning current for a deflection winding, a parabolic voltage developed at the deflection winding is superimposed on the oscillator direct current operating voltage in such a proportion that an increased parabolic voltage level, indicative of excessive scanning current from either an overscan or low operating frequency condition, causes the oscillator to operate at a higher frequency which decreases the deflection winding current and therefore the parabolic voltage and thereby permits the use of less expensive circuit components having lower maximum voltage level ratings.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.