Apparatus for simultaneously coupling computer video signals to a local color monitor and a distant monochrome monitor
US5299306A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 12, 1990 |
| Grant date | Mar 29, 1994 |
| Priority date | — |
| Expiry date | Oct 12, 2010 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L25/08
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Circuitry is disclosed herein for coupling VGA analog video signals Red, Green, and Blue from a computer to a first signal conditioning circuitry including signal splitting circuitry for providing two sets of the VGA signals. One set of these signals is provided to a color monitor located proximate the computer, and the other set is provided to a cable up to 300 feet in length and having a plurality of discrete conductors. The conductors are coupled at an opposite end of the cable to a second signal conditioning circuitry and to an analog monochrome monitor, the second signal conditioning circuitry including voltage reduction means for reducing the Red, Green, and Blue signals to a reduced, different voltage level for each signal. The reduced signals are then summed to form a monochrome video signal that is provided to the monochrome analog monitor, the color signals each displayed thereon as a different shade of gray in accordance with a reduction factor of each of the voltage reduction means.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.